Epistemology_APH 214

APH 214 – Epistemology
Third Year, Semester. V, 2022
Department of Philosophy, School of Arts and Humanities, University of Juba
Instructor: Andrew Anda Wöndu [0920069779 * andrew.wondu@gmail.com]
Course Description
Epistemology, also known as Theory of Knowledge, studies the nature, structure, scope, and
limits of knowledge. It aims to discover and illuminate the grounds on which our beliefs are
justified. In other words, how do we know what we know? Or do we really know anything at all?
Questions we wish to explore will be such as:
 What is it that we ultimately seek in knowledge? I.e., what is the goal, understanding,
utility (techne), wisdom, or something completely different?
 What are the necessary conditions for something to be considered “knowledge”?
 Is it allowed to reason in a circle?
Course Objectives
(1) Exposure to contemporary issues in epistemology, concerning the nature, sources, methods,
and scope of knowledge.
(2) Examine the rational (or irrational) grounds on which the validity of the convictions of
human knowledge.
(3) Identify the centrality of epistemology to other branches of philosophy.
Main Texts
Sven Bernecker and Duncan Pritchard (eds.). 2011. Routledge Companion to Epistemology.
London and New York: Routledge, Taylor and Francis.
Michael Huemer (ed.). 2002. Epistemology: Contemporary Readings. London and New York:
Routledge.
Ernest Sosa, Jaegwon Kim, Jeremy Fantl, and Matthew McGrath (eds.). 2008. Epistemology: An
Anthology (2nd
ed.). (Malden, MA: Blackwell Publishing).
Course Content
I Foundational Concepts
1. Introduction
1.1 Plato’s epistemology
— Theory of Forms
— The Good as the object of knowledge
— Kinds of knowledge: skills, arts, etc.
1.2 Aristotle’s epistemology
— Theoretical and practical reason
— Socrates, wisdom and virtue

Plato, Theaetetus 201, Meno 98, Parminedes
Aristotle, Metaphysics; Nicomachean Ethics
2. Truth and Belief
2.1 Opinion and Belief: Implicit and explicit belief. Dispositional attitudes.
2.2 Theories of truth
— Facts and Evidence
— Correspondence theory. States of affairs
3. Scepticism
3.1 Pyrrhonian scepticism.
3.2 Cartesian scepticism (Descartes, Meditations I, and II.)
3.3 Humean scepticism
4. Rationalism: Reason and the a priori
4.1 The a priori and a posteriori
4.2 The understanding/intellect’s faculties: perception, critical reflection, deliberation.
4.3 Cognition. Discursive reasoning, conceptualization, introspection and abstraction.
*Inference*
4.4 René Descartes
5. Empiricism: Empirical knowledge and the a posteriori
5.1 John Locke
5.2 George Berkeley
5.3 David Hume
— Cause and Effect
— Custom and Habit
— Hume’s problem of induction
5.4 Immanuel Kant
II Sources of Knowledge
6. Perception
6.1 Sensation: the nature and boundaries of experience
6.2 Perceptual justification, perceptual judgements: the problem of the external world.
6.3 The problem of perception.
6.4 Perceptual illusions. Imagination
6.5 Sense-datum theory (Russell)
6.6 Phenomenalism
6.7 Verificationism
6.8 Realism and idealism
6.9 Direct/Naïve realism; Disjunctivism
6.10 Pragmatism
7. Testimony and Memory
7.1 Transmission (of information)
7.2 Authority
7.3 Media
7.4 Social epistemology
7.5 Memory
2

CAT 1
III Analysis of Knowledge
8. Knowledge as justified true belief (JTB)
8.1 Epistemic vs. non-epistemic justification (normative vs. descriptive)
8.2 The regress of justification problem [Cf. 11.5]
8.3 Gettier problems
9. Internalism and Externalism
9.1 Internalism
— Availability and cognitive accessibility
— Mentalism
— Access mentalism
9.2 Externalism
— Evidentialism – one’s evidence entirely determines what one is epistemically justified
in believing (Locke, Hume, Russell).
— Reliabilism - “I have always said that a belief was knowledge if it was (i) true, (ii)
certain, (iii) obtained by a reliable process” (Ramsey 1931).
IV Structure of Knowledge
10. Foundationalism and Coherentism
10.1 Traditional (internalist) versions of Foundationalism
10.2 Externalist versions: Evidentialism, Reliabilism, and Infinitism
10.3 Foundationalist and Coherentist responses to the Regress of Justification problem, and
their respective internalist assumptions.
10.4 Logical and mathematical knowledge
— Deductive inference
— Primitive notions, Axioms and Postulates
CAT 2
EXAMS
3

The term epistemology is from the Greek episteme meaning “knowledge” or “understanding”. And
logos, which has various meanings such as sentence, discourse, order, but roughly corresponding to
“the study of”. The beginning of epistemology in the Western tradition is credite`d to Plato (428–
348 BC). The subject is present in many of his works, but it is in three: Meno, Theaetetus, Sophist,
and Parmenides that they are examined in depth and at length. In these dialogues, the characters
engage in depth about the nature of knowledge. How is knowledge possible? What is the object of
knowledge? How is error possible?
There are many sorts of things that people claim to know but involve a different kinds of
knowledge. In Gorgias, a Sophist. Socrates questions him what his art is. A hierarchy or skills, arts,
is the constructed. Technology, techne. We may know how to make wine, or know that a certain act
is good or bad. Or our knowledge can be even more mundane, we may (claim) to know that you are
in a classroom, or that you are angry. Notice that these are contingent.1
The fact that you are angry
or in a classroom may change without my becoming aware of it. In that case, my assumption, my
“knowledge” is no longer correct.
1.1 Plato’s epistemology
Plato’s epistemology is strongly linked to his metaphysics. 2
According to Plato, 3
there are two
types of knowledge, each corresponding to a fundamental division of reality. Knowledge of our
common, material world, the world of objects. And knowledge of the world of Forms, the world of
Ideas. The things we encounter everyday world is not the real world, but just “shadows of reality”.
Compare with Aristotle in Prior Analytics and Posterior Analytics, to know a thing is to know what
caused it to be, the principle that underlies it, its essence (ousia). Therefore, real knowledge must be
that which is not contingent on situations. It must be eternal and unchanging. The perfect example
and paradigm of this was mathematics, necessary truths.
In the Republic, Plato’s sets forth his theory of how we come to have knowledge of the Forms
through what are called the “four stages of cognition.” At the first or lowest stage of knowledge,
called imagination (eikasia), we are commonly aware of; what we encounter the objects presented
through sense-perception. These are not at all the real things. The second is called pistis, the stage
of belief. Here, we may have true belief and have correct opinions (doxa), but we are still in the
world of appearances. It is only on the third stage called dianoia do we enter what is called rational
insight and properly begin understanding anything. This is like in science where we begin with the
visible objects given to us, but proceed to uncover the hidden realities behind them. In the last stage
we use intelligence (noesis) and dialectical inquiry , everything that was accepted as an assumption
is rejected, they become mere hypotheses. The objective in this stage is to come to the knowledge
that can serve as the foundation for all others. It is only on this stage do we encounter the Forms
themselves. [To Plato, there exists two worlds. The Form of the Good (agathon), the highest object
of knowledge, is the ultimate reality and exists alongside other Forms in the world of Ideas. Our
common world is the second, the world of Appearances.] 4
1 I.e., they/the case could have been different. We can perceive the same things differently. We will look at this more
in Lesson 4 on perception.
2 Robert Heinaman, “Plato: metaphysics and epistemology.”
3 The problem with the phrase “Plato says.”
4 Aristotle’s major criticism of Plato’s theory of Forms is that, if the two realities are completely separate Substances,
it is not clear how they interact. Furthermore, the Forms are said to be motionless, yet things do indeed move.
Aristotle proposes instead that everything is made Matter (hyle) and Form (eidos). Matter is the actually material
that composes a thing. This includes what he called “prime matter”, the potential for a thing to receive a form. Form
to Aristotle means the particular structure that makes a thing what it is. The essence of a thing is what separates it
from all others. Things of the same class and that have the same nature serve a common purpose, this is its (or their)
form. In directly answering Plato’s dualism, he says that matter and form never exist independently of each other.
1

Plato’s “Allegory of the Cave” illustrates our relation of our knowledge about reality. In the
allegory, there are group of prisoners in a cave who are tied to chains and have never left the cave.
Furthermore, they have their backs to the entrance of the cave and so cannot see outside. There is a
fire burning behind them that projects shadows onto a wall in front of them. They therefore see
various objects’ shadows; men; animals, and others. If a prisoner were freed, he would have to turn
and face the blinding light. If he came back to the cave and explained that what they saw of the wall
were just the shadows, and not the real things in-themselves, would his fellow prisoners accept his
version? The blinding light is alluding to the Sun, which illuminates the real world or truth but at
the same time is painful.
1.2 Plato’s metaphysics
[Plato’s discussion of Forms takes place in the context of knowledge. Particularly of things in
general, and of ultimate reality in general.] The purpose of education is to lead us to an
understanding of true reality behind the appearances of things, and the ultimately, the
Transcendental Good. The Good (agathon) is like the Sun, we are able to see because of it. The
Forms of Good is the cause of knowledge and truth. Reason can be trusted to lead us to the truth
only when it is motivated by the love of the Good. To know something, therefore, is to know its
Form. Properly speaking, we do not “learn” anything new. In his other dialogues such as
Parminedes and Theaetetus – where he properly discusses the nature of knowledge – it’s stated that
the Forms (including human Form) are eternal and co-existed in prior to our birth (and co-mingling
with Matter). All Forms are therefore known to each other. Knowledge is simply a matter of us
“remembering” what we were once acquainted with in the World of Forms. Knowledge is
recollection of Forms/Ideas.
1.2 Aristotle’s Theoretical and Practical Reason
According to Aristotle, to know something is to know its essence, its function, what is capable of
being, this is its potentiality. When its potentiality has been realized, it can said to be actualized in
an actual things. For example, a seed’s purpose is to develop into a tree of some sort. This is the real
meaning of matter and form: The Form is the actuality and Matter is the potentiality. While Plato
was unable to explain motion (kinesis) in the world, Aristotle sees the entire universe as eternally in
motion. This explains the movement from actuality to potentiality that is responsible for the
existence of all things. There must be however have been a First Cause or eternal Prime Mover that
instigated the entire process, this is what Aristotle calls God. To know a things purpose or its final
end, what Aristotle entelechy, we must also know how they come into existence, what caused them
to exist as they do. He explains this by four “causes.” 5
Knowledge for Aristotle was not a purely theoretical affair, it was supposed to be practical as well.
Knowledge should help us to develop a good character and to live a good life. But what is “good”
for human beings? Plato’s view was that is what is good or excellent means is when something or
someone acts according to their role or function. To know the good in Plato’s thought of course,
means simply to know (or “remember”, rather) what good acts are. The Greek word for “good”
(arête) is the same as that for “virtue.” 6
Aristotle had much in common with Socrates. The aim of
5 The material cause is the physical material that composes a substance. The efficient cause is the immediate trigger
of an object or event. The formal cause, its structure or arrangement, and the final cause is the purpose for which an
object or event exists.
6 Aristotle partly agrees with Plato that the virtue of anything is what it is good for. And all men desire to be happy.
But similar to Thrasymachus’ objections to Socrates in the Republic, he says that happiness is not the same for
everyone. Some desire wealth, others power, and others honour. Happiness does not come in an instant but
throughout our lives. Therefore, unlike Plato, to know what good is, we must constantly perform good acts until
they become a habit. Virtuous acts, moral virtues, aren’t determined by an absolute measure, but are rather a middle
2

knowledge was cultivation of virtue, distinguishing good from evil. Socrates of course denied that
anyone could be taught, or wisdom (sophia) instilled. We tend to feel strongly what is real, and the
knowledge of it, must be eternal and unchanging, not contingent. Next Lecture will be one Truth
and Belief.
In Book VI of the Ethics that Aristotle discusses intellectual virtues and distinguishes between
theoretical and practical sciences (episteme), a distinction that is not found in Plato’s thought.
According to Aristotle, there are two rational faculties, one that aims at knowledge for the sake of
knowledge and the other that aims at knowledge for the sake of action.
Theoretical or scientific knowledge is knowledge that does not admit of any variation, which is not
subject to change by human volition, and which exists by an unalterable necessity. Metaphysics
(what Aristotle sometimes calls First Philosophy), physics and mathematics are sciences of this
kind. Practical reason, or the calculative faculty, is concerned with that which is contingent and
subject to change by human volition and which admits of exceptions. It aims not at knowledge for
the sake of knowledge but at knowledge for the purpose of action. Ethics, political science, and
economics are practical sciences. Not only do the two kinds of conclusions they differ in the kinds
of conclusions they reach. The theoretical sciences yield truths that are universal and necessary,
truth that are deducible with logical necessity from self-evident principles. The practical sciences,
however, yield truths that hold true only in the majority of cases, and their conclusions are always
subject to exception.
Associated with the use of theoretical reason are the theoretical (dianoetic) virtues, or ways of
knowing. The most fundamental of these is insight (nous), or what might be called rational
intuition, the capacity to grasp the truth of first principles. It includes the capacity to define our
terms with precision. When it because a fixed habit, we say that person has intelligence. Another
intellectual virtue is the ability to think syllogistically, i.e., to arrive at a correct conclusion from a
given premise through a middle term. The highest intellectual virtue is wisdom (sophia), which
Aristotle defines as ‘intuitive reason combined with scientific knowledge—scientific knowledge of
the highest objects which has received as it were its completion’.7
The ability to engage in
contemplation about ultimate reality is what Aristotle.
References
Gadamer, Hans-Georg. 1986. The Idea of the Good in Platonic-Aristotelian Philosophy. Translated
and with an Introduction and Annotation by P. Christopher Smith. New Haven and London: Yale
University Press.
Heinaman, Robert. “Plato: metaphysics and epistemology” in Routledge History of Philosophy, Vol.
1: From the Beginning to Plato, Ch. 10, p. 329–63.
Plato, Meno in Complete Works, 1997. ed. by John M. Cooper Indianapolis, IN: Hackett Publishing
Company.
Code, Alan. “Aristotle’s logic and metaphysics” in Routledge History of Philosophy, Vol. II – From
Aristotle to Augustine (Ed. David Furley). Ch. 2, pp. 40—75.
2. Truth and Belief
2.1 Opinion and Belief
An opinion is a thought about a thing, but one acknowledged to be purely subjective. Opinions can
be consequential or mundane. You probably don’t care what a stranger’s opinion about your family
ground between two extremes: the golden mean.
7 Aristotle’s Ethics, Bk. VI, 7, 1141a.
3

is. A doctor’s opinion, or a mechanic’s, you take seriously (more so if it’s about your health,
personal or automotive). A belief is also a thought about a thing or situation. But is different from an
opinion in two important respects.
i) Although they have a subjective element, they make a universal claim.
ii) They are much more deeply held than opinions.
Beliefs can in fact (most the time) define an individual’s world-view. The clearest case is with
religious belief. The word faith is conventionally reserved for this strong kind of belief. But even
common beliefs can have a big role in your life. You believe the buses will operate tomorrow. You
believe there will be no military invasion from Egypt. And then there are scientific beliefs,
historical beliefs: You believe the sun will rise tomorrow. You believe there were two World Wars,
and so on.
We can divide beliefs into implicit and explicit beliefs. Explicit belief is one we are conscious of
and have maybe stated it so. An implicit belief one which we are not aware of, but others are able to
recognize it. A negative variety is the bias. You have probably come across people
There exist a class of “feelings” that are about objects, concrete or abstract, that we cannot neatly
call beliefs. These include such usage as “I hoped she’d come”, “I trust this car”, “I fear the night
brings danger. We call these dispositional attitudes.
2.2 Theories of Truth
Aristotle says “truth is to say what is, that it is” (Metaphysics,). Whatever the nature of knowledge
may be. We can identity certain characteristics. The chief one being that it must be true. We speak
of wanting to know “real opinion”, and his “true opinion”. Equally stronger is the description of
“true” belief and faith. Is an un-reality a truth? An un-truth a reality? A fake flower is not a flower.
Fake news is not news. But they both have similar function (enchant, or inform (or misinform)).
Fake sugar and fake meat. Some people want the “fake”. A new reality. Natural and artificial foods
are not easily distinguished.
2.2.1 The correspondence/representational
Correspondence theory and representationalism are the oldest explanation or account of the nature
of truth, and of how we can give an account for the logical behaviour of truth.
Aristotle’s classical conception of truth captures an intuition that most of us share,
To say what is that it is not, or of what is not that it is, is false, while to say of what is
that it is, or of what is not that is not, is true.
Or in other words, the truth of sentence consists of its agreement with reality.
The correspondence theorist of truth conceives of thought as separate from reality and of truth as
consisting in a match between the two. The identity theorist disagrees: thought is answerable to reality
for its truth—if a thought is true, this is because of the content of reality—but there is not the gap here
that the correspondence theorist imagines. This disagreement has taken the shape of a disagreement
over facts. According to a traditional correspondence theory, facts are those elements of external
reality by which thoughts are measured: for a thought to be true is for it to correspond to a fact. The
identity theory agrees that facts are elements of reality but denies that they are external to thought.
Rather, a fact is a possible object of thought, it is something a subject may think, and thoughts—that
is, thinkings—contain their objects (Johnston 2013, p. xx) .
4

For our beliefs to be true, they must correspond to facts, or state of affairs, or events. The next
question is what constitutes these states of affairs? Are they constituted by objects alone, or also
properties? Whatever the facts or states of affairs are, we must all agree of them since we share a
common world. Truth must be objective.
The correspondence theory uses the Objectivity intuition as a starting point. But like the other
traditional theories we’ll discuss, it isn’t content to end there. It aims to explain the Objectivity truism
by giving a general account of the nature of truth. According to that account, beliefs are true just when
they correspond to reality. In the early twentieth century, for example, Wittgenstein (1922) and
Russell (1966) developed a version of the correspondence theory of truth according to which beliefs
(or their propositional contents) were true in virtue of sharing a common structure with the facts.
According to this view, beliefs such as the cat is on the mat exhibit a certain form; and objects (cats,
mats) and relations (being on) compose basic facts that also exhibit a logical form or configuration.
Thus a belief corresponds as a whole to a fact just when they share the same form or structure (Lynch
2011, p. 4).
Truth is being defined as belief that has parts that represent parts of concepts or relations, its
denotation. A belief is true if and only if the object denoted has the property predicated of it.
Concepts can denote or refer to objects as well as properties. For example, the if the concept CAT
causes you have thoughts of cats as black, then the concept is true.
2.2.2 Coherentism
Coherentism is an alternative to correspondence theory. It doesn’t demand that each belief be
necessarily true, just that the totality of beliefs about a particular thing together support each other.
That they do not contradict each other. We will discuss it in Topic 12 – Foundationalism and
Coherentism. Except there we are talking about the structure of knowledge, not only truth.
* Facts and evidence *
2.3 Verificationism
Verificationist epistemological theories that conceive of truth as a matter of language. We can only
speak of the truth of a sentence, if it is verifiable and established in experience, or if it’s possible to
do so at least. /* We will therefore leave in depth discussion of verificationism for philosophy of
language next year */
Alfred Tarski will later formulate a semantic definition of truth that based on the interpretation we
give to terms in sentence.
2.4 Pragmatism
Where correspondence theories give [pride of place] to Objectivity, their historical rivals, the
coherence and pragmatist accounts of truth, [privilege] End of Inquiry.
The American philosopher Charles Sanders Peirce’s (the founder of pragmatism) view of truth,
simply identifies truth with that end: “The opinion which is fated to be ultimately agreed to by all
who investigate is what we mean by truth” (Peirce, 1878/2001: 206).
End of Inquiry: Other things being equal, true beliefs are a goal of inquiry.
Rather than saying that we agree on what is true because it is true, Peirce’s thought is that what is
true is so because we agree on it. No mention is made of our thought’s having to represent or
correspond to some independent world of objects.
5

There may be such a world, but if so, truth is [shorn] free of it on this account.
References
Johnston, Colin. 2013. “Judgment and the identity theory of truth”, Philosophical Studies (2013)
166:381–397
Lynch, Martin P. 2011. “Truth”. In The Routledge Companion to Epistemology. (eds. Sven
Bernecker and Duncan Pritchard.) London and New York: Routledge, pp. 3–13.
Peirce, C. S. 1878. “How to Make our Ideas Clear,”
Schwitzgebel, Eric. 2011. “Belief”. In The Routledge Companion to Epistemology. (eds. Sven
Bernecker and Duncan Pritchard). London and New York: Routledge, pp. 14–24.
3. Scepticism
Scepticism (or skepticism as Americans spell it) is a tradition/strand/tendency in philosophy that is
doubtful about our ability to gain knowledge. It may be absolute, denying the possibility of any
access to knowledge. Or it may qualified, that is, claiming that the knowledge we possess is
uncertain and subject to revision. In this lecture we will discuss three kinds as articulated by the
most influential sceptics.
The ‘epistemological turn’ and Aristotle’s legacy, dogmaticism.
The widespread notion that the beginning of the Hellenistic period is marked by an
‘epistemological turn’ rests on considerations both philosophical and historical. From
the philosophical point of view, it seems natural to suppose that the birth of an
epistemology worthy of the name –that is to say, of systematic reflection on the
possibilities and the limits of knowledge, on its criteria and its instruments – implies
the prior existence of a sceptical challenge; for there must be something to jolt us out
of the naive complacency which marked our initial forays into the field of
knowledge before we had taken stock of the intellectual means at our disposal. The
gage will be thrown – and picked up – only by men who have already lost their
epistemological virginity (Brunschwig 1999, p. 229).
Sometimes in the attempt at “correction our manners, and extirpation of our vices”,
philosophy (like religion) pushes the mind more towards them with more determination “by
the bias and propensity of the natural temper” (Hume, An Enquiry Concerning Human
Understanding, Sec. V, § 34).8
The Academic or Sceptical philosophy (as Hume calls it), however, “seems little liable to this
inconvenience.” It speaks of confining the enquiries of the understanding to very narrow bounds. Of
knowledge without demonstration.
Until Aristotle, it was taken for granted that knowledge is possible. The focus was on its nature,
origin, and structure. But it is not truth, but error, which raises the deepest philosophical problems,
since the time of Parmenides. Zeno’s paradoxes and statements such as “this sentence is a lie”
(The Liar Paradox). With Epicurus and Zeno the Stoics, there was always a tradition of pre-
Aristotelian sceptics.
8 Hume, An Enquiry Concerning Human Understanding. Section V – Sceptical Solution of these Doubts, § 34.
6

3.1 Pyrrhonian scepticism
Pyrrho of Elis (360 – 270 BCE), twenty years younger than Aristotle, also incidentally accompanied
Alexander the Great through his Asian military campaign. Like Socrates he never wrote anything,
so his views must be deduced from his followers the Neo-pyrrhonians, particularly Sextus
Empiricus.
Pyrrhonian scepticism is wary of any epistemological thesis. Such as “there is knowledge” or “there
is no knowledge.” “None of us knows anything not even whether we know or do not know this very
thing (sc. that we do not know anything)” (Quoted in Brunschwig 1999, p. 237).
It’s because of views like these that some philosophers saw Pyrhho, not Plato, as the real heir to
Socrates.
Sextus’ best-known work, Outlines of Pyrrhonism (usually known by the
abbreviation PH, the initials of the title in Greek) actually begins by making this
very point. Sextus distinguishes three possible positions or attitudes: some people
think that they have discovered the truth, some people think that the truth cannot be
apprehended, and some people are still searching. It is the second position—one that
Sextus, rightly or wrongly, associates with certain of the Academics—that is
evidently closest to what in modern times has been understood as skepticism. But it
is the third stance, not the second, that Sextus describes as the skeptic’s. In fact the
Greek word skeptikos means “inquirer”; the skeptic is actually defined as someone
who keeps on searching, as opposed to someone who has come to a definite position
—including a definite position to the effect that knowledge is impossible. The latter
kind of position is just as subject to Sextus’ criticism as a form of “dogmatism”—his
favorite term for a non-skeptical outlook—as are positive views about the nature of
things (Bett, 404).
Do you think being a Pyrrhonian would affect one’s lifestyle? For example, would we be lazier?
3.2 Cartesian scepticism
Cartesian scepticism refers to Rene Descartes, the founder of modern philosophy. However, the
term refers to the scepticism inspired by him and not his own scepticism. Descartes project was to
defend the possibility of knowledge. Specifically, of the existence of God. Cartesian scepticism as
used today refers to a kind of absolute scepticism, a denial of knowledge, (or methodic doubt).
3.3 Humean scepticism
Hume’s aim is to study the “science of man”, based on experience and observation. More a
psychological interest than epistemology about how belief arises of the unobserved.
The Problem of Induction – what justifies the inference that from past events, the same can be
expected. We are being “induced to expect” effects.
Causes and effects are discoverable, not by reason, but by experience.
22. “All reasonings concerning matter of fact seem to be founded on the relation of Cause and
Effect. By means of that relation alone we can go beyond the evidence of our memory and senses.”9
Must a ball fall down. When playing billiard balls; a hundred different events might as well follow
from a single hit. Hume’s point here is not that, having established, via inductive inference, that the
two “species of event” are constantly conjoined, we infer that the first is a cause of the second;
9 Hume, Enquiry, Section IV – Sceptical Doubts concerning the Operations of the Understanding, Pt. 1.
7

rather, our inferring the second event and our thinking of it as an effect of the first are two sides of
the same coin, the inference supplying the impression of necessary connection on the basis of which
we make the causal judgment.
Custom and Habit
This principle is Custom or Habit. For wherever the repetition of any particular act
or operation produces a propensity to renew the same act or operation, without being
propelled by any reasoning or process of understanding, we always say, that this
propensity is the effect of Custom.
All inferences from experience, therefore, are effects of custom, not of reasoning.10
“All belief of matter of fact or real existence is derived merely from some object, present to the
memory or senses, and a customary conjunction between that and some other object.” (Hume 1751,
p. 38)
Adam could not know that water would drown him. The explosion of gunpowder, intricate
machinery, etc. the causes could not be known a priori.
Looking forward
Scepticism has been defeated for now… Lecture 4 – Rationalism, is about the tradition of
Descartes regarding the source of our knowledge or, Ideas. In Lecture 5 – Empiricism, the
opposing team, championing experience, empirical knowledge. This includes philosophers such as
John Locke, George Berkeley, and David Hume.
References
Beebee, Helle. “David Hume” in Routledge Companion to Epistemology (730–40)
Bett, Richard. “Pyrrhonian Skepticism” in [...] (404–13).
Brunschwig, Jacques. “Introduction: the beginnings of Hellenistic epistemology” in The
Cambridge History of Hellenistic Philosophy, 1999. (eds. Kiempe Algra, Jonathan Barnes,
Jaap Manself, and Malcolm Schofield). Cambridge: Cambridge University Press, pp. 229– 59.
Descartes, René. 1641/1922 Meditations on First Philosophy [1911 edition of The Philosophical
Works of Descartes (Cambridge University Press)].
Hume, David. 1751/1977. An Enquiry Concerning Human Understanding. A Letter from a
Gentleman to His Friend in Edinburgh (ed. Eric Steinberg). (Indianapolis, IN: Hackett
Publishing Company)
Larmore, Charles. 1998. “Scepticism” in The Cambridge History of Seventeenth-Century
Philosophy, Vol. 2. (eds. Daniel Garber and Michael Ayers). Cambridge: Cambridge University
Press, p. 1145 – 92.
Luper, Steven, “Cartesian Skepticism” in Routledge Companion to Epistemology (414 – 24)
4. Rationalism: Reason and the a priori
10 Ibid., Section V – Sceptical Solution of these Doubts, Pt. 1, 36.
8

February 2022
Plato’s epistemological concern was around the question “What is the source of our ideas?”. What
kind of knowledge is the highest? Is it [a] science? The question of how dependent our knowledge
is on our sense experience historically put philosophers in two camps; rationalists and empiricists.
Although the distinction is not absolute, most empiricists claim that all our knowledge comes from
experience, whereas rationalists argue that some of our knowledge and concepts have other sources.
Ancient philosophers from Plato and Aristotle advocated a form of rationalism.
Synonyms of “rational” are; reasoning, ratio, rationation. All imply a balancing, a weighing of two
quantities or entities. Being irrational and being unreasonable mean the same. Reasoning is what
happens when we consider, we weigh, different experiences and make an inference of what we
thing is really the case. How we turn beliefs into knowledge.
There were disagreements among rationalists during the Renaissance period (14th
- 16th
centuries).
The modern form however, has its source in René Descartes. Other major rationalists from the
early modern period (17th
century) include: Thomas Aquinas, Gottfried Leibniz, Baruch Spinoza,
and Blaise Pascal.
Rationalists try to advance their claim by demonstrating that we are in possession of certain
knowledge that cannot have been gotten from sense experience. This kind of knowledge or
conceptual frameworks that we are born with is variously known as innate ideas or a priori
knowledge. Furthermore, they attempt to show reason alone could have provided that that
knowledge. In reaction, an empiricist would answer the challenge by showing how the particular
knowledge can indeed [only] be acquired from sense experience, this is called a posteriori
knowledge. If it cannot be so acquired, empiricists usually advocate a form of skepticism – that it is
impossible to know (with absolute certainty).
4.1 Descartes (1596–1650) was student of the Jesuits, who followed the teaching of St. Thomas
Aquinas from the medieval era, i.e. the middle ages (~ 400 – 1500 CE)
In Meditations, Descartes aimed to seek truth only through reason. Not satisfied with the skepticism
of the day. He set to find a few fundamental truths and set them of a solid foundation. The truths are
not all new, but he would demonstrate a rational and systematic order, whether previously affirmed
or not. His inquiry (sceptikos) centered on the ego, which told different and sometimes
contradictory stories. By discovering the nature of the ego, thereby the laws of its natural function.
The Birth of the Cartesian Problem
10 There is an instinct that causes human nature to abhor ignorance, the acute form of which is
skepticism. Human nature was made for the truth.
11 There was identification in his time, or probability with error; error is the source of doubt.
The most striking thing about mathematics was its internal evidence, and absence of dissension
among mathematicians (not really true). True knowledge must be evident. Evidence and truth must
be interchangeable. Since Scholasticism has so many probabilities, it must be erroneous and the
cause of skepticism.
9

12 He identified the nature of the ancient philosophers with popular and non-scientific
knowledge, the results of prejudice with an illusion of truth, therefore responsible for the spread
of skepticism.
How can the same reason be the cause of truth in mathematics and falsity in philosophy
(probability)? Sensations do not bring clarity. Next he rejects all thoughts including geometric
demonstrations, dismissing them as illusions. The only thing that can’t be rid of is the fact that he’s
doubting. To doubt is to think, and to think is to exist. This is the first truth. The ego contains no
object but itself, it does not require anything in order to acquire ideas. It is a pure spirit. With such a
nature of infallibility, the mind can’t by itself commit errors. The truth comes from clear and
evident idea.11
3 If the mind is not responsible for errors, the source of errors must be in the mind’s union
with the body.
4 All possible and imagination are rooted in sensation. Once the working of the ego is known,
we understand how truth and error occur in the same person.
Knowledge is knowledge of the truth, which is infallible, one which is like mathematical truth. But
both of these ideas are reductionist, a simplification. (1) Mathematical truth is not the only truth in
the ego. (2) The starting point is equivocation, if only mathematical truth is truth, we aren’t dealing
with human knowledge.
We can doubt whether our impressions of reality are indeed reality, but we can we doubt our
impressions of reality? No. Man is not two substances (body + soul), the activities of the one are as
much the activities of man as the activities of the other. (the ghost in the machine, Gilbert Ryle).
To think, alone is an inseparable part of our nature, as Descartes argued. What we ultimately are,
our essence is mind, an intellect, an understanding, a consciousness, a self-awareness, etc.
Now, faculties of this intellect/understanding include: perception, deliberation/introspection,
cognition/thinking, discursive reasoning/critical reflection, etc.
4.2 Gottfried Leibniz (1649–1677)
Following the premise that substances are by their nature self-contained leads to the conclusion that
the world consists of innumerable simple substances –monads. God is the super-monad. Monads
must be “windowless”. Monads do not interact. A monad’s “perceptions” are not perceptions in the
usual sense but internal states that correspond to the internal states of all of the other monads in a
“pre-established harmony” established by God.
Leibniz is generally classified as a successor of Descartes in the Rationalist tradition, but in
one way this classification is misleading: it tends to suggest a greater similarity between
them in epistemology than really exists. It is true of course that both philosophers urge that
genuine knowledge is to be achieved by turning away from the senses, and they emphasize
the superiority of the pure intellect over the imagination. But in general Leibniz’s approach
to epistemology is very different from Descartes’. Unlike Descartes Leibniz was never
greatly exercised by the problem of radical skepticism, and he was critical of Descartes’
method of doubt as a starting-point in philosophy. Indeed, Leibniz’s conception of the role
of epistemology in philosophy aligns him more with the third major Rationalist, Spinoza,
than with Descartes. In his most important expository works, such as the Discourse on
11 Cf. Charles Sanders Peirce, “How to Make Our Ideas Clear”.
10

Metaphysics, Leibniz, like Spinoza in the Ethics, generally seeks to deduce a theory of
knowledge from metaphysical premises. Whether or not he was directly influenced by him,
Leibniz shares Spinoza’s conviction that the proper method in philosophy is to begin with a
theory of substance and to derive epistemological consequences from that theory.
Significantly, the most striking area of agreement between Leibniz and Descartes in
epistemology involves a doctrine that is by no means uniquely Cartesian: both
philosophers revive the ancient doctrine of innate ideas and knowledge found in Plato’s
Meno. Leibniz’s indebtedness to the Platonic and Neo-Platonic tradition in philosophy
is arguably of vital importance for understanding his whole theory of knowledge. One
of the main theses of Leibniz’s philosophy, one that is never seriously questioned, is
that the human mind is a mirror or image of God; Leibniz also expresses the point by
saying that the human mind is a “little God.” This Neo-Platonic theme helps not only to
explain his commitment to the theory of innate knowledge, which can be seen as an
epistemological expression of the “mirror” principle; but also to explain his impatience
with the kind of radical skepticism that Descartes took as his point of departure in
philosophy (Jolley 2011, p. 697).
4.3 Baruch Spinoza (1623–1677)
Substances are by their very nature completely self-contained, there can be only one substance:
God. The distinction between creator and creation, “God” & “nature” is illusory: pantheism.
4.4 St. Thomas Aquinas (1224 – 1274 CE)
Thomas Aquinas was a Catholic monk of the Dominican Order. He is a so-called Doctor of the
Church. He held that sense perception brings the external world into our field of knowledge. We
also have intellectual knowledge. In the presence of the perceived, our minds forms a concept.
Man’s knowledge begins in the senses and ends in the intellect. The senses make a singular, distinct,
concrete image. The intellect retains the common aspect of the class, the universal, general, and
abstract. This is acquired through two stages
(1) Sensitive cognition – the object is the particular.
(2) Intellective stage – the universal.
The senses are in in potency towards the individual form, the intellect is in potency towards the
universal form. To obtain the universal presupposes we have sensible knowledge of the object.
Abstraction is passing from sensitive cognition to intellective cognition.
Aquinas refers to Aristotle; the particular form as potentially universal. If the sensible form can be
immaterialised, it will assume the form of the universal. Aquinas posits an intellectual agency, the
passive intellect – allows the intellect to receive the intelligible species. The form, both individual
and intelligible, is not what the mind grasps, it is only the means by which the mind understands the
object.
(1) Knowledge has a foundation in the reality in the metaphysical.
(2) Cognitive faculty, which is potency until it is actuated by the object, becomes one with the
form that actuates it.
(3) What is truth: it consists in the equality of the intellect with its object, adequatio intellectus et
rei: conformity found both in sensitive cognition and the idea.
Errors in cognition come from
(1) Judgment – assign an object, attribute predicate to subject it doesn’t belong to.
(2) Discussing reason – derive knowledge of the particular from the universal.
References
11

Descartes, Rene. Discourse, Meditations, [1911 edition of The Philosophical Works of Descartes
(Cambridge University Press)].
Des Chene, Dennis. 2006. “From natural philosophy to natural science” in The Cambridge
Companion to Early Modern Philosophy (ed. Donald Rutherford). Cambridge: Cambridge
University Press, 67–94.
Gaukroger, Stephen. 2006. “Knowledge, evidence, and method” in The Cambridge Companion to
Early Modern Philosophy (ed. Donald Rutherford). Cambridge: Cambridge University Press, 39–
66.
Jolley, Nicholas. 2011. Gottfried Wilhelm Leibniz. The Routledge Companion to Epistemology.
(eds. Sven Bernecker and Duncan Pritchard.) London and New York: Routledge, Taylor and
Francis, pp. 697–706.
Wilson, Margaret. 2006. “Spinoza’s theory of knowledge”, in The Cambridge Companion to
Spinoza (ed. Don Garrett). Cambridge: Cambridge University Press, 89–142.
5. Empiricism
Both (Continental) rationalists and (British) empiricists are in agreement about the primacy of sense
experience. An explanation of how sensations lead to perception and ultimately ideas and
knowledge is critical to each. The reliability of our senses in providing us with accurate information
about our world becomes a matter of serious concern. If our senses are liable to error, truth and
falsity about anything is unattainable and certainty will always be elusive.
It has often been taught, and may in dark corners still be taught, that in the
seventeenth century epistemology was transformed by a new notion of 'ideas' as the
immediate objects of perception and thought. Henceforward, it was said, philosophy
was saddled with 'representative' theories of perception and knowledge that gave rise
first to the metaphysical isolation of the mind and then to the thoroughgoing idealism
of the following century. In the eighteenth century itself, the realist Thomas Reid
saw the Cartesian theory of ideas as the error which, by insinuating a veil or tertium
quid between the mind and reality, set philosophy on a course leading logically to
the scepticism of Hume (1062).12
5.1 Locke's representative realism
Locke’s epistemological motivation is the imperfection of language for the clarification of
thought.13
The greatest part of the Questions and Controversies that perplex Mankind [depend] on the
doubtful and uncertain use of Words, or (which is the same) indetermined Ideas, which they are
made to stand for" (E Epis: 13)
1. What is an idea? "Whatsoever is the Object of the Understanding when a Man thinks."
2. We can know of the existence of external object although not with the certainty of our "intuitive
Knowledge, or the Deductions of our Reason, employ'd about the clear abstract Ideas of our own
Minds." Bk. 4, Ch. xi, para. 3
12 Michael Ayers, “Ideas and Objective Being” in The Cambridge History of Seventeenth-Century
Philosophy, Vol. 1.
13 Woolhouse, Roger, “Locke’s theory of knowledge” in The Cambridge Companion to Locke, edited by Vere
Chappell. Cambridge: Cambridge University Press, pp. 146.
12

3. About ideas we cannot help but have: shows that there is an exterior cause acting upon the senses.
4. Words on a page: what he decides to write in his mind, and directs his hand to write, is indeed
what does appear on the paper. The words continue to exist as they are written and continuously
affect the senses (unlike fancies or memories). Another person could come and make the sound that
is represented by the words.
John Locke strongly denied the existence of any innate ideas and believed all our knowledge comes
from experience. From sensation and reflection.
First, Our Sense, conversant about particular sensible Objects, do convey into the Mind,
several distinct Perceptions of things, according to those various ways, wherein those
Objects do affect them: And thus we come by those Ideas, we have of Yellow, White, Heat,
Cold, Soft, Hard, Bitter, Sweet, and all those which we call sensible qualities, which when I
say the senses convey into the mind, I mean, they from external Objects convey into the
mind what produces there those Perceptions. This great Source, of most of the Ideas we
have, depending wholly upon our Senses, and derived by them to the Understanding, I call
SENSATION. Paragraph 3, Book II, Chapter i)
There exists an object that is perceived, the subject who perceives the object. Between them is the
idea. To Locke, idea means a sensation. Objects have qualities that have power to produced ideas or
sensations in the subject. Locke distinguishes two kinds of qualities; primary and secondary
qualities. Primary qualities are powers in the object that are inseparable from the object, they exist
in them in the way we perceive them, extension and solidity are primary qualities. Secondary
qualities are from the mind, the power in the object to produce ideas. Our sensations of secondary
qualities is like colour is indirect, like a translation. The theory is named representative realism for
that reason. We thus never directly perceive objects, substances are a series of ideas.
The Notice we have by our senses, of the existing of Things without us, though it be altogether so
certain, as out intuitive Knowledge, or the Deductions of our Reason, employ’d about the clear
abstract Ideas of our own Minds; yet it is an assurance that deserves the name of Knowledge. (Book
IV, Chapter xi)
We error whenever the idea does correspond to a power in the object, or the object doesn’t
exist at all.
When-ever the Mind refers any of its Ideas to any thing extraneous to them, they are capable to be
called true or false. Because the Mind in such a reference, makes a tacit Supposition, as it happens to
be true or false, so the Ideas themselves come to be denominated. (Book II, Chapter xxxii) 14
Possible objections to Locke’s theory are:
2 How are ideas caused by substances?
3 How does a mental event cause a physical event?
4 If we cannot directly perceive substances, how do we know they exist?
5.2 Berkeley's Subjective Idealism
George Berkeley, Bishop of Cloyne (1685-1753) was another great British empiricist. In one his
major works, A Treatise Concerning the Principles of Human Knowledge (1710), “the chief causes
of error and difficulties in the sciences, with the grounds of scepticism, atheism, and irreligion are
inquired into.” 15
Berkeley’s position is called idealism because it holds that “sensible things” are
14 Ibid., p. 41.
15 Robert Audi, Introduction in Epistemology: Contemporary Readings (ed. Michael Huemer (New York, NY:
Routledge, 2002), p. 20.
13

ideas or clusters of ideas. Sensory objects have no existence of their own. Their existence depends
on being perceived (esse est percipi). There is no substance of an apple, only a set of ideas of
redness, and sweetness, etc. As it’s impossible for me to perceive anything without an actual
sensation of that thing, so is it impossible to conceive in my thoughts any sensible thing or object
distinct from the sensation of perception of it.16
Like Locke, Berkeley felt that language was important in solving philosophical disputes. Our
common words are “misty” and “veiled”. Some words have no meaning philosophically
(“substance”). What could be there underlying the perceived? There is not a clear meaning to the
word “support”. There is a multiplicity of use. We commonly suppose the purpose of language is
the communication of ideas. But it’s sometimes used to raise some passion, excite or deter some
action. Generally, to put the mind in some particular disposition.
Sensory objects have no existence of their own. Their existence consists of being perceived by a
mind. To be is to be perceived. To exist is to perceive. “Sensible things” are ideas. All knowledge is
about ideas. Only persons can properly exist. Material substances don’t exist.
The two qualities of Locke are not distinct to Berkeley, primary qualities can’t be perceived alone.
We can easily imagine a big or small ball, but it can’t be colourless, even if black or white.
To others, primary and secondary qualities, they exist in the mind, primary in the object. The two
qualities are not distinct. If the relativity of secondary qualities provides argument for their
subjectively, the same also for primary qualities. Sensible are clusters of ideas. (realm natura).
Ordinary language disassociates ideas from objects. A “thing” which generally denotes something
existing outside the mind. An “idea” inside the mind. To Berkeley, a “thing” includes ideas. “Ideas
of…”. He comes to the following conclusions:
1 Ideas are not representations of things, but the things in themselves.
2 Ideas are not intermediaries for knowing the thing, they are objects for sense perception.
3 Locke’s material substance does not exist (matter, corporeal substance).
* * *
Berkeley has two criteria for determining error in perception. A knowledge claim is consistent if can
allow us to predict how one idea follows another. A report is public if other people can verbally
verify it. Evidence when added to true opinion, yields knowledge. 17
Berkeley was forced to modify his system under strong criticism that he was denying the existence
of objects. He insisted that things like trees and houses are quite real, as ideas. The tree that falls in
the forest continues to exist even when no one is there because God perceives it. “God preserves
not only the uniformity of nature but the consistency among the perceptual reports of all people.”18
There are Ideas of sense, caused or coordinated by God. And Ideas of imagination, which are under
our control.
5.3 David Hume (1711 – 1776)
Hume reduces knowledge to impressions. The impressions come first, ideas are the immediate
experience. Every possible object of knowledge is based on perception: phenomena. 19
Perceptions
16 René Descartes, The Meditations Concerning First Philosophy, trans. Laurence J. Lafleur, in Philosophical Essays
(Indianapolis, IN: Bobbs-Merrill Educational Publishing, 1964), p. 76.
17 Ibid., Ch. II. “Of the Nature of the Human Mind, and that It Is More Easily Known than the Body.”
18 Roderick Chisholm, Theory of Knowledge. (Englewood Cliffs, NJ: Prentice-Hall, 1966), p. 30.
19 Humean Impressions and Kant’s Notion of Intuition: the Necessary Connexion
14

of the mind are either thoughts/ideas or impressions. The former being with less force. All our ideas
are copies of impressions [Section II]. So all our knowledge is of perception, there are two types of
knowledge
(1) Matters of fact
(2) Relations of ideas
We learn matters of fact through the senses or by connecting cause and effect. Causal relations can
only be known by experience. We assume a necessary connection between ideas. We know the
connection through experience. Through Association of Ideas 20
“Three principles of connexion
among ideas, namely, Resemblance, Contiguity in time or place, and Cause or Effect” (Sec. III).
“Experience is possible only through the representation of a necessary connection of perceptions.”
Persistence of substance, succession (law of causality), and simultaneity (law of
reciprocity/community.
In the garden of Eden, Adam and Eve couldn’t have known that water would drown them. We can
neither discover the effect in the cause, nor the cause in the effect. We only get to know things
though custom and habit. By combining different experiences we get reflections, ideas.
The consequence is Hume’s problem of induction, where most of our scientific and common day
beliefs, laws, and knowledge can’t be rationally justified.
We have autonomic processes such as breathing. What levels of autonomy do they have? How
much thinking and control is involved. Do your hands and feet sometimes anticipate what you want
them to do? These kind of questions have become part of sub-discipline known as philosophy of
action.
“We are every moment conscious of internal power; while we feel, that, by
the simple command of our will, we can move the organs of our body, or
direct the faculties of our mind.”21
5.4 Kant’s “Critical Philosophy”: Transcendental Idealism
Immanuel Kant wrote that “We are in possession of certain a priori cognitions, and even the
common understanding is never without them”.22
His goal was to bridge the rationalist and
empiricist views. But this needs distinguishing pure cognition from empirical ones.
“First, then, if a proposition is thought along with its necessity, it is an a priori judgment.”
Philosophy stands in need of a science which shall determine the possibility, principles, and extent
of human knowledge a priori. All cognition comes from sensibility or understanding.
— Transcendental Aesthetics – the objective value of sensible experience
Transcendental aesthetics is a critical examination of sensibility.. In all our judgments, if we
eliminate (by critical analysis) … a primitive “given” remains. That “given” double two traits:
13 It imposes itself on from without so that we are passive with regard to it
14 It is contingent. This allows it to furnish as the variety of fact required by scientific
experiences. . Perception is a faculty, which implies being active, yet it’s passive by nature. In
order to receive the impact, there must be a passive faculty (receptivity). This function can’t
cause sensibility. That which sensibility receives constitutes the materials of experience. The
20 Kant calls them Analogies of Experience
21 Hume, Section VII – Of the Idea of Necessary Connexion, Part I, §51
22 Immanuel Kant, Critique of Pure Reason. Translated by Paul Guyer and Allen W. Wood.
Cambridge/New York: Cambridge University Press, 1998.
15

particular aspect is the sensation. The whole act Kant sensible intuition, sense experience. In
order for this experience to be produced, something besides sensation is required.
Space and time are a priori forms of intuition, sensibility. Space is the a priori form of external
intuition, and time of internal intuition. They place the role of necessity and universality. If the two
are suppressed, every sensible action is destroyed. The suppression of every particular leaves the
universal in themselves. They are universal because they are required for all acts of sensibility. The
two are opposed to the given, which functions as matter. Space and time play the determining role
of form. These are imposed on the sensations. Kant compares them to spectacles. The empiricists
were correct that all knowledge begins with experience. But the rationalists are also right that there
is an a priori form which knowledge must conform to. We use this to make judgments about things
we have not experienced.
— Transcendental analytics – the objective value of intellectual knowledge
The question Kant wanted to answer was “How are synthetic a priori judgments made?”
Analytic statements are explicative, they bring out. E.g. “All bodies are extended.”
Synthetic statements are augmentative, they add on. E.g. “All bodies are heavy.”
But consider, "Everything that happens has a cause".
In the conception of something that happens, I indeed think an existence which a certain time
antecedent, and from this I can derive analytical judgments. But the conception of a cause lies quite
out of the above conception, and indicates something entirely different from "that which happens,"
and is consequently not contained in that conception. The synthesis (of cause and effect) cannot
come from experience because of its universality and necessity.
5 Concepts are necessary. It is necessary to add to sensible knowledge a function of an active
and superior faculty; - the understanding. It plays the role of clothing the sensible given to make
it an object of thought, imparting universality. No longer a sense experience, a thought
experience,23
a concept.
Locke’s physiological derivation of concepts, ascending from perceptions to general concepts, an
empirical deduction of pure a priori concepts is not possible, should be independent of experience
because it relates to their future use.
Sense knowledge is partial because the forms lose their universality and necessity when uniting
with the given, matter. Time and space get concretized so that the pure sensible phenomenon
becomes identified with the passing and the individual act our consciousness. The phenomenon is
incapable of being an object endowed with truth. The phenomenon, as sense experience, can furnish
an element for a true judgment. Sense experience, even when expressed in judgment form remains a
purely synthetic judgment without any scientific value. Two things necessary to obtain truth are 1)
something sensible is given, 2) that alone insufficient (?).
The phenomenon and the concept are too opposed to be unified without an intermediary. The
intermediaries are the 12 schematisms of the imagination.24
These pertain at the time to the sensible
23 Is It an Experience That We Think? Is intuition a judgment or a perception? (Godel, Frege,
Kant).
24 Kant’s Division of the Faculties of the Soul: Sense, Imagination, and Apperception [cf. Hegel]
16

by its concrete elements and to the intelligence by their determination. They’re grouped under 4
Categories:
4 Quantity – there is a universe
5 Quality – matter is composed of simple elements
6 Relation – the world is related to sensibility and thought
7 Modality – we don’t all exist in the same way
The synthesis has laws – Principles of Pure Understanding. These are fundamental principle of all
true knowledge—which is in synthetic a priori judgments, a complex whole that
7 Involves, sensible intuition + space and time = phenomenon
8 The intermediary, the schematism
9 The concept – the a priori form of understanding
Having demonstrated the necessity of concepts. The concept without sensible intuition is empty.
Intellectual positivism, idealism is a special kind – only positive or experimental science is valid.
Object must not extend the phenomenon perceived by the senses. “The things itself remains
unknown. The laws of nature explained by the laws of spirit, universality from a priori forms
Nature gravitates around our spirit.
Kantian ethics
1 Truth is normative, a property of synthetic a priori judgments alone.
2 These laws are in the mind.
3 Universal consent is the secondary criterion for truth.
4 Error comes when understanding follows these laws without consideration.
References
Audi, Robert. 2002. Introduction in Epistemology: Contemporary Readings (ed. Michael
Huemer (New York, NY: Routledge, 2002), p. 20.
Ayers, Michael. 1998. “Ideas and Objective Being” in The Cambridge History of Seventeenth-
Century Philosophy, Vol. II (eds. Daniel Garber and Michael Ayers). (Cambridge: Cambridge
University Press, pp. 1062-1107).
Hume, David. 1751/1977. An Enquiry Concerning Human Understanding. A Letter from a
Gentleman to His Friend in Edinburgh (ed. Eric Steinberg). (Indianapolis, IN: Hackett Publishing
Company).
Kant, Immanuel. 1787/1998. Critique of Pure Reason. Translated by Paul Guyer and Allen Wood.
Cambridge/New York: Cambridge University Press.
Woolhouse, Roger. 1994. “Locke’s theory of knowledge” in The Cambridge Companion to Locke
(ed. Vere Chappell). Cambridge: Cambridge University Press.
6. Perception
6.1 Perception and Sources of Knowledge
For anyone on the path of knowledge—philosophers especially—discerning knowledge from belief
or opinion is a central concern. In Plato’s Meno, Socrates engages with the young Meno first about
17

the nature of virtue and whether it can be taught. The topic later shifts to the nature of knowledge
itself and what can be taught. In the dialogue Socrates remarks,
That there is a difference between right opinion and knowledge is not at all a
conjecture with me but something I would particularly assert that I know. There are
not many things of which I would say that, but this one, at any rate, I will include
among those that I know. [97C]. 25
Of the various sources of knowledge such as, memory, testimony, and inference, perception is held
to be the primary contributor. 26
The others are dependent in one way or another on perception: they
need perceptions to provide the necessary data for cognition. It is through perception that we first
learn about the world around us. Barry Stroud writes,
The importance of the senses as a source or channel for knowledge seems undeniable. It seems
possible, then, to acknowledge their importance and to assess the reliability of that source, quite
independently of the difficult question of whether all our knowledge comes to us in this way. We
would then be assessing the credentials of what is often called “experiential” or “expirical”
knowledge, and that, as we shall see, is quite enough to be going on with. 27
6.1 Sensation, perception, and the nature of experience
And what is perception? 28
It is sense experience, sensation. Sensation traditionally refers to the
five senses: touch, smell, taste, sight, and hearing. They are physical, nerve stimulations.
Perceptions are the ordering patterns we impose on them. They are “representations accompanied
with sensation”, hence empirical. (Kant, Critique of Pure Reason, B 147).
The Boundaries of Experience
What is it for something to be an object of immediate (or direct) awareness or to be given?
The immediateness of experience means that is not falsifiable. When someone says “I
heard/saw/felt it”—assuming that the claim is an honest one—she is right whether or not she is
mistaken about what she saw, but she definitely saw something. It’s a phenomenological claim, not
an epistemological one.
The purpose of the five senses is to detect external things/objects. But There are times when we use
perceptual verbs in a non-mental sense. Such as, “I feel happy”. These are not strictly perceptual
reports. I.e. they are not telling us about a sense-perception outside the body. But how do we
classify internal experiences? External experiences are physical in nature, they obviously involve
the body coming in contact directly with something external. But even perceptual experiences of
this kind are not always the same. “ (called kinaesthetic).
What Counts as Experience, Empirical, Kinesthetic. A Posteriori? Inner Sense
The consciousness of oneself in accordance with the determinations of our state in internal perception
is merely empirical, forever variable; it can provide no standing or abiding self in this stream of inner
appearances, and is customarily called inner sense or empirical apperception (Kant, CPR, A 107).
Inner States. Are brain states experiences or do we experience brain states?
25 Plato, Meno, trans. G. M. A. Grube, in Complete Words, ed. John M. Cooper (Indianapolis, IN: Hackett Publishing
Company, 1997), 870-97.
26 Locke believed in revelation also as a source of knowledge. As did many ancient thinkers especially of a religious
background such as the Christian, Islamic, and Indian theologians.
27 Barry Stroud, (2000). Understanding Human Knowledge. Oxford: Oxford University Press.
28 Compare the etymology of "perception”: per cieve, percepi (perceived), percipient, cidere, discern. Perceive,
percept, perception.
18

An intuition (in Kant’s terms) is direct awareness of something, or its truth.
All representations, as representations, have their object, and can themselves be
objects of other representations in turn. Appearances are the only objects that be
given to us immediately, and that in them which is immediately related to the object
is called intuition (Kant, CPR, A 109).
The difference between what is external and internal corresponds to the difference between a
perception (or percept) and a conception (or concept). 29
Conceive - late 13c., conceiven, "take (seed) into the womb, become pregnant," from Latin
concipere "to take in and hold; become pregnant," from capere "to take,",- "to grasp" (see capable).
Meaning "take into the mind" is from mid-14c., a figurative sense also found in the Old French and
Latin words.
6.3 Perceptual justification: the problem of the external world
It is through perception that we first learn about the world around us. The question of how
trustworthy are our senses are is best illustrated by what is known as the problem of the external
world. Put simply, the first and most crucial piece of information we seek from our senses is to
verify the nature of the world outside us (and more critically, its existence, because we could simply
be in a dream state). Various philosophical positions on perception are customarily contrasted with
that is the necessary conditions for perception.
6.2 The problem of perception
The epistemological problem of perception is; how can our beliefs about the external world be
justified by our senses and perceptions. How are we to explain the errors made by our senses? A
single object can appear differently to two people. A pencil in a cup of water appears bent when it
is, in fact, straight.30
Ancient philosophers called it the problem of the one and the many. The
emotions we feel and things we see in our dreams seem just as real as waking life sensations. In
fact, how can we know that we not dreaming at all? Capaldi writes that perceptions can come in
forms, whether corresponding to something is reality or not. The truth or falsity is unverifiable in
one way, but self-confirming as true.
It is literally meaningless to talk about correct or incorrect perceptions. Every perception, even if it
is an illusion or a hallucination, exists, is real, etc., in the sense that it cannot be incorrect. Only
descriptions of what is seen can be termed correct or incorrect. The stick appears bent in the water,
but it is incorrect to say that the stick is bent.
The problem of error, the epistemological problem, is more correctly stated as the problem of
justifying or rejecting perceptual statements (judgments, claims, etc.). (p. 41) 31
The involuntary nature of perception is what distinguishes it from the cognitive faculties, which are
active. Kant’s system builds on the passivity of the senses (receptivity). The following phenomena
show this. 1) Neural receptors can fire without cause. 2) Muscle memory exists for those skilled in
playing musical instruments. 3) Phantom pains and phantom limbs in amputees.
The coherence of sense-experience.
29 Cf. Incept, inception; Intercept, interception; excerpt, etc.
30 Plato, Theaetetus. M. J. Levett, rev. Myles Burnyeat, trans., in Complete Words, John M. Cooper
(ed.). (Indianapolis, IN: Hackett Publishing Company, 1997) 233
31 Barry Stroud, ‘The Problem of the External World’, in Epistemology: An Anthology, 2nd
ed., eds.
Ernest Sosa et al (Malden, MA: Blackwell Publishing, 2008), p. 10.
19

We are perceiving the same sense-data, the error comes in the judgment. Secondary qualities are
relative, "sweet," "loud,". Light and dark, then contours, then complex things like faces.
Imagination’s role in aesthetics and art.
According to P. F. Strawson, “Imagination is a necessary ingredient of perception.” When we
encounter an object, some of whose parts are hidden, we imagine the missing parts (Nanay, 2010).
Fig. 1 – Perceptual constancy
6.4 Direct/Naïve Realism
Common man’s opinion of how they think perception works. That is position is called
direct realism (or naïve realism by detractors, because of its simplicity). In direct realism,
there exist the subject who directly perceives the object. The object as it appears to us is its
real nature.
Intriguing because we can consider what it would be like to directly perceive an object.
Immediate experience - the nervous system interacts with things outside it, to directly
perceive something means our nervous system surrounding it, it being inside it.
6.5 Sense-datum theory of Russell (G. E. Moore, J. S. Mill)
"Let us give the name of 'sense-data' to the things that we are immediately known in sensation: such
things as colours, sounds, smells, hardness, roughness, and so on. We shall give the name
'sensation' to the experience of being immediately aware of these things." (Russell, The Problems of
Philosophy, Ch. I, Appearance and reality)
"When we are trying to show that there must be objects independent of our own sense-data, we
cannot appeal to the testimony of other people, since this testimony itself consists of sense-data,
and does not reveal other people's experiences unless our own sense-data are signs of things
existing independently of us."
Consider case of dreams, you are aware of something, but it’s difficult to prove their existence
outside of our imaginings.
20

"It is true that, when the physical world is assumed, it is possible to find physical causes for the
sense-data in dreams: a door banging, for instance, may cause us to dream of a naval engagement.
But although, in this case, there is a physical cause for the sense-data, there is not a physical object
corresponding to the sense-data in the way in which an actual naval battle would correspond."
(Russell, The Problems of Philosophy, Ch. II, The existence of matter)
3] Observation-statements/propositions: Confusion and Falsifiability of Verbal / Perceptual /
Sensory Reports: the Logical Foundations of Phenomenalism [Mill]
6.6 Phenomenalism
Refining Berkeley's Subjective Idealism. Differs from idealism in that it holds that objects exist
insofar either as they are perceived or as it is possible to perceive them.
Permanent possibilities of sensations. "It wasn't X, but it could've been X." (J. S. Mill)
The act of perceiving → The object perceived
Perceptual Illusions
The argument from illusion/perceptual relativity/hallucination.
1. Sense experience is subject to illusion: some ordinary objects do not have features
they perceptually appear to have.
2. [The “Phenomenal Principle”]: Whenever something perceptually appears to have
a feature when it in fact does not, we are directly aware of something that does actually
have that feature.
3. If what we are immediately aware of has a feature the ordinary object does not, we
are not in such cases immediately aware of the ordinary object.
4. Even in veridical situations, we are immediately aware.
Fig. 2 – Perceptual Ambiguity and Distortion
Syneasthesia – a crossover of sense modalities. When sensations cross over into another sense
organ. Tasting sounds, etc. (Ideasthesia)
Causality (causal nexus) between ideas. Causal relations can only be known by experience. (Hume)
There is "no intrinsic difference in kind between those of our perceptions that are veridical in their
presentation of material things and those that are delusive."32
32 Ayer, The Foundations of Empirical Knowledge.
21

Veridical and delusive perceptions may form a continuous series. Thus, if I gradually approach an
object from a distance I may begin by having a series of perceptions which are delusive in the sense
that the object appears to be smaller than it really is. Let us assume that this series terminates in a
veridical perception. Then the difference in quality between this perception and its immediate
predecessor will be of the same order as the difference between any two delusive perceptions that are
next to one another in the series....
It seems most extraordinary that there should be a total difference of nature where there is only an
infinitesimal difference of quality.33
6.7 Linguistic phenomenalism (The Adverbial Theory)
There is "no intrinsic difference in kind between those of our perceptions that are veridical in their
presentation of material things and those that are delusive."34
J. L. Austin criticizes the sense-datum theory in Chapter 1 of Epistemology.
Delusions and illusions: the illusions in Ayer's "argument from illusion" are not illusions at all.
"The argument from illusion is primarily intended to persuade us that, in certain exceptional, abnormal situations, what
we perceive-directly anyway-is a sense-datum; but then there comes a second stage, in which we are to be brought to
agree that what we (directly) perceive is always a sense-datum, even in the normal, unexceptional case. It is this second
stage of the argument that we must now examine" (Austin, Sense and Sensibilia, 1962).
There is a difference between veridical and delusive perceptions.
Appearances are adverbial, not substantive. By this it’s meant that we may be perceiving the same
things, but our descriptions of them may vary. We may use different language to describe the
phenomenon.
Disjunctivism (Indirect Realism)
While a perceptual experience in a case of illusion or hallucination may perhaps be an
awareness of something like sense-data or adverbial contents, the only object of experience
in a case of veridical perception is a mind-independent material object.
Summary
The dominant philosophical position remains against extreme scepticism; knowledge is possible
and perception is the primary source of that knowledge. Locke and Berkeley’s reactions to
Descartes’ perception have formed the backbone of modern theory of knowledge. Contemporary
theories like sense-data theory, phenomenalism, linguistic realism and all follow upon improving on
the subjective idealism of Berkeley.
There is much experimentation and scientific work on the mechanics of perception that needs to be
done by physiologists and psychologists in order to better answer the epistemological problem of
perception. But the conceptual framework still remains in any knowledge. The answer might turn
out to be a linguistic or philosophical one.
References
[1] Austin, J. L. (1962) Sense and Sensibilia. Oxford, Clarendon Press.
[2] Ayer, A. J. (1946–7) “Phenomenalism,” Proceedings of the Aristotelian Society 47: 163–96.
33 H. H. Price, Perception (London: Methuen & Co., 1950), p. 31.
34 A. J. Ayer, The Foundations of Empirical Foundation (London: Macmillan & Co., 1963).
22

[3] Ayer, A. J. (1952) "The Elimination of Metaphysics," Language, Truth and Logic. New York:
Dover Publications, pp. 33-45.
[4] Berkeley, George. (1710) A Treatise Concerning the Principles of Human Knowledge. In The
Works of George Berkeley, Bishop of Cloyne. (1948-57) ed. by A. A. Luce and T. E. Jessop, 9
vols. London: Nelson.
[5] C. D. Broad. (1947) "Professor Marc-Wogau's Theorie der Sinnesdata," in Mind, pp. 1-30, 97-131.4
[6] Capaldi, Nicholas. (1969) Human Knowledge: A Philosophical Analysis of its Meaning and
Scope. New York, NY: Pegasus
[7] Chisholm, Roderick. (1966) Theory of Knowledge. Englewood Cliffs, NJ: Prentice-Hall, Inc.
[8] Chisholm, Roderick, “The Problem of the Criterion"
[9] Chisholm, Roderick. (1957) Perceiving: A Philosophical Study. Ithaca: Cornell University
Press.
[10] Descartes, René. (1964) Philosophical Essays. Laurence J. Lafleur, trans. Indianapolis, IN:
Bobbs-Merrill Educational Publishing.
[11] Huemer, Michael. (2002) Epistemology: Contemporary Readings. New York: Routledge.
[12] Hume, David. (1748/1977) An Enquiry Concerning Human Understanding (ed. Eric Steinberg).
Indianapolis, IN: Hackett Publishing Company.
[13] Kant, Immanuel. (1781/1996) Critique of Pure Reason. trans. Werner S. Pluhar.
Indianapolis/Cambridge: Hackett Publishing Company, Inc.
[14] Lewis, C. I. (1946) An Analysis of Knowledge and Valuation. LaSalle, Ill.: Open Court, pp. 171-90
[15] Locke, John. (1959). An Essay Concerning Human Understanding. New York, NY: Dover
Publications, Inc.
[16] Mill, J. S. (1865) An Examination of Sir William Hamilton's Philosophy Ch. 11 or the 3rd ed.
[17] Moore, G. E. "Proof of an External World"
[18] Moore, G. E. (1953) Some Main Problems of Philosophy (New York: Macmillan), Chpts. 2, 5,
& 7.
[19] Nanay, Bence. (2010) “Perception and imagination: amodal perception as mental imagery”.
Philosophical Studies 150: 239 – 254.
[20] Russell, Bertrand. (1912/1997) The Problems of Philosophy (New York: Oxford University
Press.
[21] Russell, Bertrand. (1917) Mysticism and Logic. New York: Barnes & Noble, "The Relation of Sense-Data to
Physics."
[22] Sosa, David. (2011) “Perceptual Knowledge”, The Routledge Companion to Epistemology.
(eds. Sven Bernecker and Duncan Pritchard.) London and New York: Routledge, Taylor and
Francis, pp. 294–304.
[23] Sosa, Ernest, Jaegwon Kim, Jeremy Fantl, and Matthew McGrath. (2008). Epistemology: An
Anthology, 2nd
ed. Malden, MA: Blackwell Publishing.
[24] Vernon, M. D. (1962). The Psychology of Perception. Baltimore, MD: Penguin Books.
8. Memory and Testimony
I. Memory
“If you have authentic memories, then you have real human responses
… We recall with our feelings. Anything real should be a mess, not
detailed.” – Dr. Ana Stelline (Blade Runner 2049)35
Swampman and Teleosemantics
35 Compare Rachel and q-memories, transference of consciousness (transporter technology in Star
Trek): “the q-memory must bear the right sort of causal connection to the original experience.”
23

Swampman is an imaginary molecule-for-molecule duplicate
of a person (created, let’s say, by random chance when lightning hits a swamp).
Teleosemantics implies that swampman has no representational states, because he
has no evolutionary history. Some have taken intuitions about swampman to be a
basis for objecting to a theory of content. As we will see shortly, intuitions have little
probative value for our kind of project (§2.2). Nevertheless, the swampman case is
important, because it highlights an implication of the theory. It forces us to reflect on
whether there are good reasons for representational content to be based on history
(Shea 2018, 22)
8.1 Representative/Indirect Realism and Direct Realism
Memory is an ability to recount, recollect, re-tell, and remember past experiences. It is a cognitive
system that encodes, stores, and retrieves information. In this, it works closely with the perceptual
system. Philosophical discussion of memory, therefore, follows that of perception. The same
questions asked of perception may be asked of memory: what are we aware of when we remember?
I.e. what is the object of memory? The traditional view/answer is called representative/indirect
realism—what we remember are representations of past sense-experiences. Advocates of some form
of this theory are Locke, Hume, and Russell.
Though there is a past that causes us to have memory experiences, we are not
directly or immediately aware of the past. What we are directly aware of are the
effects the past has on us—representations or sense-data of things past. We
remember something not by way of being directly aware of that thing, but rather a
mediating representation of that thing. To remember is to undergo a certain sort of
mental experience; it is to experience a mental representation which reproduces
some past sense-experience (Bernecker, 326).
Just as in theory of linguistic phenomenalism about perceptions, there is no intrinsic difference
between veridical and illusory rememberings. But how can we know the past, and furthermore, that
it caused the present? “How can we discriminate memory representations from other
representational states such as figments of the imagination?” (Bernecker, 327). The answer is
memory markers – a priori knowable features of memory representations on the basis of which they
can be distinguished from other mental phenomena. Representative realists have characterised
memory in a number of ways:
— The feeling of warmth (William James)
— The feeling of familiarity and pastness (Bertrand Russell)
— The force and vivacity of memory representations (David Hume)
None of these markers are entirely reliable, they’re sometimes present when there’s no memory to
speak of. And sometimes they’re absent from memory instances. Then, what is the justification for
associating these markers with memory? Evidence can’t be purely from reflection. Or if there is a
general principle whereby we trust our cognitive faculties absent assurance of reliability, the
memory markers aren’t very useful.
Conversely, direct realism says that we are directly aware with memories, just as in perception. It
derives some of its plausibility from the fact that when we remember something, what we are aware
of is just that thing, and nothing further. If we are directly aware of the past event itself, there is no
need for an inference of a past occurrence from a present memory representation. [By internally
24

representing the thing, not by being aware of the internal representation of the thing.] However, new
problems arise:
1 How to explain our direct acquaintance/experience of past things?
2 Direct realism might be incompatible with the (intuitive) causal theory of memory, For S to
remember p, his representation of p must be suitably causally connected to his first
representation of that same p.
Hume held that causal relations can’t be know a priori. That’s because cause-and-effect is a
metaphysical, not logical relation. The cause and the effect must be “independent existences”.
Hume was worried that if cause and effect were linked by a logical relation, there wouldn’t be any
room left for causal efficacy, it’s worth, its ability to change things. But we could always restate the
effect in a way that makes it an entailment of the cause, that it follows from it.
Causation is a relation between propositions and linguistic entities. And just
because there is a logical relation between the descriptions of two events
doesn’t preclude that the events themselves stand in a causal relation
(Bernecker, 328).
No matter the answer, possessing knowledge—learning—entails a lasting change in behaviour or
mental processes that results from experience. Therefore, we must first acquire the knowledge (a
priori or a posteriori), strengthen some important, weaken others, and eventually retrieve it. This is
the role of memory. But is it an independent source, or does it merely shape other sources?
8.2 Does Memory Imply Knowledge?
According to received wisdom in epistemology, remembering that p implies knowing
that p.36
Propositional memory is thought to be long-standing or continuing knowledge.
Audi (2003: 69), for example, says that “if you remember that we met, you know that
we did. Similarly, if you remember me, you know me.” Memory is knowing from the past.
“Actual memories mostly are traces not of past sensations but of past
conceptualization or verbalization” (Chisholm, Perceiving, 160). 37
“This discovery of yours [writing] will create forgetfulness in the learner’s
souls, because they will not use their memories” (Plato, Phaedrus).
Propositional knowledge has three necessary conditions: (1) Belief, (2) Truth, (3) Justification.
Both memory and knowledge imply truth. I.e. truth is a component of both knowledge and memory.
Therefore, to evaluate memory we must focus on the other two. Regarding (1), it is possible to
remember something without believing it. For example, a child might have experienced some
trauma whose memories they suppressed. One day the memory re-appears, but he’s unsure of
whether it really did happen. If they were to later find evidence that the event did, he acquires a new
belief, and not simply reviving an old one. He therefore remembers the event without believing that
he remembers it, or even believing it. In case (2), S remembers p, but there is an undefeated
defeater, there is some defeating information such that, if he became aware of it, he would no longer
be justified in believing p. Questions about justification usually divided philosophers into opposing
internalist and externalist camps.
Internalism claims that something can confer justification on an subject’s belief only if it falls
within his or her perspective on the world. I.e. a mentally accessible item justifies belief p. So, we
36 To Plato’s epistemology, this is reversed: knowing (that) p is remembering p’s Form/Idea.
37 Quoted in W. V. Quine. 1960. Word and Object. Cambridge, Mass.: MIT. Press.
25

couldn’t have opposing reasons (undefeated defeaters) in the same subject. A mentally accessible
item is something that one can come to know whether it obtains just by reflecting on one’s mental
states.
Externalists say that the subject need not be aware of factor’s justifying his belief, but might also
not be aware of evidence that undermines his belief. Certain externalists add as a reliabilism as
additional condition. “In addition to the reliabilist justification condition they adopt a no-defeater
condition that ensures that a justified belief is not incoherent with the background information the
subject possesses” (Bernecker, 330).
We may therefore conclude that memory doesn’t imply knowledge since it implies neither belief
nor justification. Misleading evidence could destroy once justified belief one still remembers.
(Kennedy killed in 1963 or 1964).
8.3 Memory and Justification
Is memory merely a preservative force of justification and knowledge? Or can it function as a
generative source (on the same level as perception, reasoning/inference, etc.)?
Many of our factual memories come without any particular supporting
phenomenology
of memory images or feelings of familiarity. We cannot remember how we acquired
the information, and it may be relatively isolated, but we still use it when the need
arises. Although few if any memories stand in total isolation from the rest of our
conscious lives, very many memories are too isolated to receive impressive
justification from other internal elements (Williamson (2007: 110–11).
Preservationism says that memory preserves knowledge and justification through time, just as
testimony does between persons. But memory can’t improve the epistemic status of a belief at the
time of recall. Preservation of epistemic justification is the work of internal or conscious justifying
factors. But sometimes, our justificatory evidence might be irretrievable, or forgotten.
Internalists seem to be stuck with the implausible result that retained beliefs are
unjustified unless the past evidence is also recalled. In response to the problem of
forgotten evidence, virtually all proponents of preservationism adopt the principle of
continuous justification: at t2, S’s belief from t1 that p is continuously justified if S
continues to believe at t2 that p—even if he lost his original knowledge-producing
justification and has acquired no new justification in the meantime (Bernecker, 331).
The principle of continuous justification is the basic, or foundational, type of justification. We are
entitled to believe what memory gives us unless we have reasons to doubt it.
Generativism counters that a memory belief can not only be less but also more justified than the
original belief, and even if the original wasn’t. How? It is the phenomenology of recalling that
generates justification for memory beliefs. There are parallels with perception, where veridical and
delusive perceptions should feel or appear different.
Another problem (even conceding the distinctive phenomenology) in the epistemic boost problem
– in the absence of defeating conditions, the epistemic status of a belief slightly improves simply by
virtue of being recalled. There doesn’t seem to be a neat correlation between a belief’s epistemic
status and the number of times it is recalled or remembered.
26

Radical generativism – memory can generate new justificatory factors, new evidence. The
justification of the memory belief has two parts: a preserved component, and new component
generated by recalling.
Moderate generativism – like preservationism, memory cannot make justification from nothing.
Only way to function as such is by removing defeaters, unleashing their justificatory potential.
“Memory can generate justification by lifting justificatory elements that were previously rebutted or
undermined by defeating evidence” (Bernecker, 332).
8.4 Responses to scepticism about memory
Memory entails the truth. If you remember something, that implies that it is the case, that it’s true.
But we often think we remember something that turns out not to be true. Our memory experiences
are practically indistinguishable from imaginary experiences. How could we tell which is which?
For example, Russell’s hypothesis that if the universe were created just five minutes ago—with all
the appropriate memories implanted—could we tell? The past is gone, and we longer have access to
it. But could we use photographs, diaries, testimonies, etc. to validate ostensive memories? To do so
would have to assume that our ostensive memories are trustworthy in the first place. If we make an
inductive argument and generalize, that memories are generally reliable because it relies on past
observation with we only have memory to validate.
Lewis 38
suggests that we validate our ostensive memory beliefs by their mutual degree of
coherence (he calls it congruence). This will yield a high enough probability for us to rely on it for a
rational inferences. But coherence needs a positive degree of initial credibility in order for it be able
be amplified by memory. Such a lack of initial credibility could be due to systematic delusion. But
Lewis thinks this is incoherent and contradicts our experiences. His argument rests on the (not
accepted by all) verification condition: a statement is meaningful only if it is either an analytic
statement or is empirically verifiable. Even if this if verifiability is conceded, coherence does not
amplify probability as much as Lewis thinks.
Another answer against scepticism about memory beliefs comes from Norman Malcolm 39
and
Shoemaker. 40
They state that the general reliability of ostensible memories is an analytic truth.
Ostensible memories are reliable because (a) Someone making wildly inaccurate claims means the
person misunderstands what it means “to remember”. (It could be countered that even in such a
case, s/he must understand what “remember” means s/he distinguishes it from “to imagine”). (b) We
have a gut feeling that one’s confident memory beliefs constitute knowledge. In the end, we proceed
on trusting our memories without demanding reliability from them. Russell writes, “no memory
proposition is, strictly speaking, verifiable, since nothing in the present or future makes any
proposition about the past necessary.” 41
Still, the fact that we cannot reach epistemic rationality
without trusting our ostensive memories leads some philosophers to advance a transcendental
argument that we are a priori allowed to trust our memories unless there is a stronger reason not to.
38 C.I. Lewis. An Analysis of Knowledge and Valuation. La Salle: Open Court, 1949: ch. II
39 N. Malcolm. Knowledge and Certainty. Ithaca, NY: Cornell University Press, 1963: 193–6.
40 S. Shoemaker. Self-Knowledge and Self-Identity. Ithaca, NY: Cornell University Press, 1963: 229–34.
41 B. Russell. An Inquiry into Meaning and Truth, intro. T. Baldwin. London: Routledge, 1995: 154.
27

 The Mandela Effect – many people “remember” Mandela dying in prison in the 1980’s when
he really died in 2013 (Cerf 2020).
8.5 The Biology of Memory *** [this section may be omitted without discontinuity]
Memory needs a nervous system, specifically a brain. Let us restrict ourselves to human
memory. The “memory” of animals, insects, plants, computers, etc. function differently. (Although
the artificial memory in computers is interesting as an analogy.)42
The earliest memories are from
around 3 years, 4 months. There seems to a hierarchy in the sorts of things memory captures first,
sight, especially of faces, the mother’s voice obviously.
Three stages of memory
Sensory memory holds 12–16 items for ¼ second.
Working memory is the central executive, a phonological loop, a sketch pad. It is also known as
short-term memory.
Long-term memory has 2 main partitions:
Declarative memory for facts and events. It can be further divided into
— episodic memory stores personal experiences; it’s for remembering specific times and
events.
— semantic memory stores the basic meanings of words and concepts.
Procedural memory for perceptual and motor skills. [Does this include muscle memory? Are they
automatic, like a rubber band snapping back in place.]
Engrams are physical changes in the brain associated with a memory. Also known as a memory
trace. Engram cells are brain cells which hold a unique memory. The old theory of how memories
form is that long-term memories form in the brain as short-term ones expire. New theories show
that both types of memory form at the same time – but we only get to experience one. Certain brain
cells called silent engrams contain a memory, but do not activate when a retrieval cue is given. They
mature over weeks before becoming available for recall. If so, silent engrams may offer a way to
bring back lost memories.
“Contrary to neuroscience dogma—the neural circuit in the brain structure called the hippocampus
that makes a particular memory is not the same circuit that recalls the memory later. Instead,
retrieving a memory requires what scientists call a ‘detour circuit’ in the hippocampus’s subiculum,
located just off the main memory-formation circuit.” The parallel circuits help us update our
memories much quicker (from hundreds to tens of milliseconds). 43
II. Testimony
“There is no species of reasoning more common, more useful, and even
necessary to human life, than that which is derived from the testimony of
men, and the reports of eye-witnesses and spectators” (Hume, An Enquiry
Concerning Human Understanding, § 88).
42 There are two types of computer memory, read-only memory (ROM) and read-only memory (RAM). RAM is
analogous to short term memory and ROM is like long term memory. ROM comes in the form of Hard disks, cd-
roms, flash drives, SD cards, etc. In RAM, inputs/perceptions are momentarily stored, relevant parts transferred to
ROM, the rest discarded, and the space re-used. It’s only in ROM can we actively retrieve information that has been
catalogued and stored.
43 Elizabeth Svoboda. “Light-Triggered Genes Reveal the Hidden Workings of Memory.”
28

Testimony includes the variety of communication intended to convey information. Testimonial
knowledge is that which is grounded in testimony, not simply caused by or accompanying it.
The content of the speaker’s testimony must be the ground of the knowledge—not other features
about the speaker. [E.g. ] We will consider three questions about testimony:
Q1. Is testimonial knowledge necessarily acquired through transmission from speaker to
hearer, or can testimony generate epistemic features in its own right?
Q2. Is justified dependence on testimony fundamentally basic, or is it ultimately reducible to
other epistemic sources, such as perception, memory, and reason/inference/rationation?
Q3. How do hearers acquire justified beliefs from the testimony of speakers? (§ 8.9)
8.7 The Transmission View (TV) of Testimony
The view that testimony transmits knowledge from the speaker to the hearer constitutes the default
position in epistemology, and the focus of much work. This viewpoint answers Q1 by drawing an
analogy with memory: Jennifer Lackey [says] “While memory is said to only preserve knowledge
from one person to another, testimony is thought to merely transmit knowledge from one person to
another. Thus, neither is a generative epistemic source” (2011, 317). There are two main theses to
this view: For every speaker A, and hearer B,
TV-Necessary: B knows that p on the basis of A’s testimony that p only if A knows that p.
TV-Sufficient: If (1) A knows that p, (2) B comes to believe that p on the basis of the content
of A’s testimony that p, and (3) B has no undefeated defeaters for believing that p, the B
knows that p.
Certain kinds of doubts and beliefs—either that a subject has or should have—contribute
epistemically unacceptable irrationality to doxastic (belief) systems, and, accordingly, defeat the
justification possessed by the target beliefs in question. There are two kinds of defeaters relevant to
condition (3) above:
A psychological defeater is a doubt or belief that is held by A, which indicates that A’s belief
that p is either false or unreliably formed or sustained.
A normative defeater is a doubt or belief that A should have, which indicates that A’s belief
that p is either false or unreliably formed or sustained.
A defeater can itself be defeated or be undefeated. Defeater-defeaters can be defeated by further
doubts and beliefs, etc. Otherwise, it is an undefeated defeater. These, and not merely defeaters, are
what are incompatible with testimonial justification.
Counter-case against TV-N: the devout creationist who nevertheless teaches evolution.
Counter-case against TV-S: the unreliable testifier who has knowledge but hearer doesn’t.
Writing is more than a change of medium, when we consider the effects (law, politics, etc.).
“Human discourse is not merely preserved but… affects its communicative function”.
It becomes a shortcut; thought — (speaking) — writing. (Ricouer, Interpretation Theory, 28).
8.8 The Statement View (SV)
“For every speaker, A, and hearer, B, B knows that p on the basis of A’s testimony that p only if (1)
A’s statement that p is reliable or otherwise truth-conducive, (2) B comes to truly believe that p on
the basis of the content of A’s statement that p, and (3) B has no undefeated defeaters for believing
that p” (Lackey, 318).
29

Epistemology_APH 214

Recommended

Recommended

More Related Content

Similar to Epistemology_APH 214

Similar to Epistemology_APH 214 (17)

Recently uploaded

Recently uploaded (20)

Epistemology_APH 214