I. Aristotle’s Life
II. Relationship to his teacher Plato:
A. While Plato’s philosophy is idealistic, inspiring, otherworldly and perfectionist, Aristotle’s is realistic, scientific, this-worldly and pragmatic.
B. Styles are different largely in virtue of what has survived. Plato’s dialogues survived, Aristotle’s lecture notes survived.
C. Picture of the School of Athens: Plato points up (to the Forms), Aristotle point down (at the world of our experience).
D. For Plato the model for knowledge is mathematics. For Aristotle it’s biology. What’s the difference? Biology relies extensively on observation.
E. Example: Plato’s social/political philosophy defines an ideal society. He doesn’t care if it’s attainable, and even tells you how it will fall apart if it is achieved. Aristotle’s looks at actual societies to see which ones work the best. He surveys 158 constitutions and decides which ones work the best in what circumstances.
III. Theory of knowledge
A. All human beings desire by nature desire to know.
B. For Plato there can be no science (rational discourse) of particular things.
For Aristotle there can be, in fact knowledge begins with the study of particular things.
C. It is a mistake to study an abstract quality in isolation form concrete exemplifications.
D. Presupposes that language and thought are congruent to the structure of reality. How could we understand nature if there is no affinity between nature and our minds?
E. The ten categories
1. What is it?
2. How large is it?
3. What is it like?
4. How is it related?
5. Where is it?
6. When does it exist?
7. What position is it in?
8. What condition is it in?
9. What is it doing?
10. How is it acted upon?
Would Plato ask the questions that have been put into the ten categories?
F. The discovery of logic, the science of arguments. Aristotle discovered that you could distinguish the form of an argument from the content of the argument. Aristotle put statements into categories and show how you can determine, based on the structure of an argument, whether or not the argument is valid.
1. An argument is valid, just in case, on the assumption that the premises are true, the conclusion must be true. If an argument is valid, the internal logic of the argument is solid. The argument can only be challenged externally, but attacking the truth of the premises
2. Validity is a matter of logical form. A valid argument can be given in favor of a false conclusion, or even in favor of a stupid conclusion.
3. Other argument forms to not reliably get true conclusions if the premises are true. There are invalid arguments.
G. First principles
1. Aristotle maintained that there were certain fundamental principles in every discipline. Although some people would like to think they can, or should, prove everything they believe, Aristotle realized that you can demand proof for the premises every time proof is offered, and impose an infinite regress. Some things are so basic as not to require proof.
2. An example would be the law of noncontradiction in logic, the claim that a statement and its contradictory cannot both be true. The trouble here is that any argument for the law of noncontradiction is going to assume the law of noncontradiction, and thereby be open to charge of being a circular argument. However, if someone doesn’t believe in the law of noncon, Aristotle will ask “Are you really saying that?” If the person says they are making a statement, then Aristotle will say that the person has implicitly accepted the law of non-contradiction. If the person says “No, I’m not really saying that,” then Aristotle says “Well, if you aren’t really saying anything, then I really have nothing to respond to,” and treat the person as a cabbage.