Immanuel Kant was an 18th century German philosopher born in Konigsberg, East Prussia. In his seminal work Critique of Pure Reason, Kant sought to determine the limits and scope of pure reason. He made two important distinctions: between a priori and a posteriori knowledge, and between analytic and synthetic judgements. Kant argued that we can only have knowledge of phenomena as processed by our minds, not of things-in-themselves. He achieved a synthesis between rationalism and empiricism by arguing that while pure reason is capable of knowledge, it cannot tell us about external reality independently of experience.

1. Immanuel Kant (1724-1804
AD)
• German philosopher
• born in Konigsberg(East
Prussia)
• brought up on Leibnizian
thought presented by
Christian Wolff

2. Nebular Theory
Nebula - is an interstellar cloud of dust
– the most widely accepted scientific explanation in
the field of cosmology
– first developed in the 18th century by Emanuel
Swedenborg, Immanuel Kant and Pierre-Simon
Laplace
– Solar Nebular Disk Model (SNDM) – came into
being with Soviet astronomer Victor Safronov

3. Critique of Pure Reason(1781)
– primary aim is to determine the limits and scope
of pure reason
– considered to be unreadable
– tried to ease his readers’ confusion by publishing
the Prolegomena to Any Future Metaphysics two
years later.

4. Critique of Pure Reason(1781)
• Two important Distinctions:
1. Priori Knowledge vs Posteroiri Knowledge
2. Analytic Judgement vs Synthetic Judgement

5. Critique of Pure Reason(1781)
Priori Knowledgevs Posteroiri Knowledge
• Priori knowledge is the necessary and
universal knowledge we have independent of
experience
• Posteriori knowledge is the particular
knowledge we gain from experience

6. Critique of Pure Reason(1781)
Analytic Judgementvs SyntheticJudgement
• In an analytic judgment, the concept in the
predicate is contained in the concept in the
subject
• “A bachelor is an unmarried man.”
• In a synthetic judgment, the predicate concept
contains information not contained in the subject
concept
• “All swans are white”
• “7 + 5 = 12” is a priori knowledge and synthetic

7. Critique of Pure Reason(1781)
• The mind does not passively receive
information by the senses
• mind arranges sensory experience in a
temporal progression and make sense of
event in terms of cause and effect
• Time and space are pure intuitions of our
faculty of sensibility
• Sensory experience only makes sense because
our faculty of sensibility

8. World of Phenomena vs World
of Noumena
– Our senses react to stimuli that come from
outside the mind, but we only have knowledge of
how they appear to us once they have been
processed by our faculties of sensibility and
understanding.
– Kant calls the stimuli “things-in-themselves” and
says we can have no certain knowledge about
their nature.

9. World of Phenomena vs World
of Noumena
• World of Noumena which is the world of
things-in-themselves
• World of Phenomena which is the world as it
appears to out minds

10. ANALYSIS
– Metaphysics relies on the faculty of reason, which
does not shape our experience in the way that our
faculties of sensibility and understanding do, but
rather it helps us reason independent of
experience.
– Kant redefines the role of metaphysics as a
critique of pure reason.
• That is, the role of reason is to understand itself, to
explore the powers and the limits of reason.

11. ANALYSIS
• Kant achieves a synthesis between the
competing traditions of rationalism and
empiricism
– from rationalism he draws the idea that pure
reason is capable of significant knowledge but
rejects the idea that pure reason can tell us
anything about things-in-themselves.
– From empiricism, he draws the idea that
knowledge is essentially knowledge from
experience but rejects the idea that we can infer
no necessary and universal truths from experience

12. ANALYSIS
• Copernican revolution
– turning the focus of philosophy from
metaphysical speculation about the nature of
reality to a critical examination of the nature of
the thinking and perceiving mind.
• In effect, Kant tells us that reality is a joint creation of
external reality and the human mind and that it is only
regarding the latter that we can acquire any certain
knowledge.

13. ANALYSIS
• Kant challenges the assumption that the mind
is a blank slate
– Knowledge is not something that exists in the
outside world and is then poured into an open
mind like milk into a cup.
– Rather, knowledge is something created by the
mind by filtering sensations through our various
mental faculties.

14. THANK YOU FOR LISTENING!
Resources:
• http://canitz.org/history-of-konigsberg
• http://plato.stanford.edu/entries/wolff-
christian/#WolCon
• http://plato.stanford.edu/entries/leibniz-
mind/#DenMinBodIntAssPreEstHar
• http://www.universetoday.com/77525/nebular-
theory/
• http://www.sparknotes.com/philosophy/kant/sec
tion1.rhtml