I. Against Plato’s forms
A. The forms are useless, and double the number of things that need to be explained
B. Forms cannot explain change
C. Forms cannot be the essence of that which they are separated from
D. It is not clear what it means for particulars to “participate” in forms
E. Third man argument. If there is a relation between the form of a chair and a chair, then doesn’t there have to be form of that relations, and the a form for the relation to the relation, and then a form for the relation to the relation to the relation, and then form of the relation to the relation of the relation to the relation, etc. etc, etc.
II. Transcendent versus Immanent Forms
A. If all the chair were to disappear in a nuclear war, for Plato the form of Chairness would continue to be
B. If all the chair were to disappear in a nuclear war, for Aristotle, for form of Chairness would be gone as well
III. Substances: What is real is the sum total of all the substances in the world
A. Substances consist of a whatness and a thisness.
1. The whatness picks out the universal properties of a thing. It makes a thing the thing that it is. The whatness is identified with the substance’s form.
2. The thisness of a substance picks out its matter. Hence for Aristotle, a rock is not a purely material object, as you might have thought, but rather a combination of matter and form.
IV. Change. Aristotle’s philosophy, unlike Plato’s, has a theory that accounts for change. A change is a change from potentiality to actuality.
V. A change has four causes. Those causes are the material cause, what the thing is made of, the efficient cause, what brought it to be the way it is, the formal cause, what the thing is, and the final cause, which is its purpose.