Aristotle criticized Plato's theory of Forms by arguing that knowledge comes from sense experience, not prior knowledge of ideal forms. Aristotle believed in empiricism and that knowledge is gained a posteriori through the senses. However, his theories of causation and a prime mover initiating motion are difficult to prove and have been criticized by later philosophers like Russell who argued the universe has no design or cause. While Aristotle's ideas influenced many thinkers, the debates between rationalism and empiricism continue without resolution.

1. ‘A’ Level Philosophy and Ethics
Notes
Aristotle – Criticisms
Aristotle and the Form
Aristotle was Plato’s student. Plato had argued that a person has prior
knowledge of the physical world through knowledge of the world of the
Form.
§ Aristotle argued that there was no concrete evidence for Plato’s claim.
§ Instead Aristotle argued that knowledge of the form of a thing came
from experience.
However, there is no direct evidence for Aristotle’s claims either. He argues
that we can have true knowledge only through direct sense experience.
Empiricism Rationalism
Empiricists believe that the world Rationalists believe that reason
is knowable through sense (without the support of external
experience. experience) is the only way to
acquire knowledge.
To understand the Empiricists better, look up Hume, Locke and Berkeley
in Sophie’s World. A good quotation to illustrate the empirical point of view is
from Hume:
If we take in our hand any volume; of divinity or school metaphysics, for
instance, let us ask, Does it contain any abstract reasoning containing quantity
or number? No. Does it contain any experimental reasoning, concerning matter
of fact or existence? No. Commit it to the flames: for it can contain nothing but
sophistry and illusion.
David Hume, An Enquiry Concerning Human Understanding (1748 )
This means that any statement that does not contain:
1. Abstract Reasoning – mathematics or logic (e.g. all bachelors are
unmarried)
2. Experimental Reasoning – sense experience and evidence is “sophistry
and illusion”.
Contrast this with Descartes, who wanted to see what knowledge he could
trust, and concluded that the only thing that he could know for certain was
that he was thinking.
Aristotle is an empiricist. He believes that knowledge is a posteriori.
However, the History of Philosophy is littered with battles between
Empiricists and Rationalists. Neither has won! While Aristotle may have a
point about Plato’s theory about Forms, there are many different claims
about knowledge.

2. Aristotle – Criticisms
Aristotle and the Final Cause
Aristotle’s “Four Causes” appear to be sensible. He offers a useful way of
thinking about the chain of causes and effects that lie behind the existence of
a thing. However, Aristotle’s Final Cause is less certain!
§ He argues that everything has four causes:
Consider a statue. It has four causes:
1. The Material Cause – the marble that it is made
from.
2. The Efficient Cause – Auguste Rodin.
3. The Formal Cause – the Thinker.
4. The Final Cause – aesthetic enjoyment?
Aristotle argues that everything has a reason for existing. However, there are
many people who would argue that the universe is entirely random, and
there is no reason or order.
§ In a famous discussion with Frederick Copleston on BBC Radio in 1948,
the Philosopher and mathematician Bertrand Russell argued that there
was no reason or design in the universe at all.
I see no reason whatsoever to suppose that the total has any cause
whatsoever. ...what I'm saying is that the concept of cause is not applicable to
the total.
Well the word 'gratuitous' suggests it might be something else; I should say
that the universe is just there, and that's all.
http://www.utas.edu.au/docs/humsoc/philosophy/ccc/slides/3g.html
Aristotle and the Prime Mover
While the sheet-and-football demonstrated that a large object could cause a
small object to move without moving itself, this does not necessarily follow in
the “real world”. For the Prime Mover to remain “Prime” it has to initiate
movement without being moved itself. For many philosophers this remains an
impossibility.
§ For Christians the Prime Mover’s unmovability is a problem, since they
believe that God can be affected in some way by prayer.
§ The Prime Mover’s status as “Pure Thought” seems to contradict
Aristotle’s empirical view of the world. Only Uri Geller is claiming that pure
thought can move physical objects!
Aristotle’s explanation is that the Prime Mover is absolute perfection –
the movement of the physical world is an imitation of the perfect
spherical motion of the Prime Mover.
§ Often people use the analogy of iron filings being attracted by a magnet –
empirical science has explained how magnetism works, but cannot
demonstrate how “imitation” by a planet can work!
2