I. Philosophy, the Beginning - Fifth Class

Aristotle:
Logic, Physics, and
Theory of Knowledge:

Handout

Written works
a) Dialogues in which his doctrines were expounded in somewhat popular language.
b) Treatises on physics, metaphysics, etc.


Biography
- Born at Stagira, a Greek colony, in 384 B.C.; died at Chalcis, in 322 B.C
- Plato was his teacher: from 18 to 37, he studied in Athens with him
- He was asked by King Philip of Macedon to become the tutor of Alexander (the Great)
- About 335: Aristotle returns to Athens and opens a school of philosophy: the Lyceum (from the location: i.e.: a gymnasium dedicated to Apollo Lyceios). It was also called the Peripatetic School because it was the master's custom to discuss problems of philosophy with his pupils while walking up and down (peripateo) the shaded walks (peripatoi) around the gymnasium.
- Very interested in natural sciences and in classifying plants and things from the natural world
- Regarded at Athens as a friend of Alexander and a representative of the Macedonian dominion.
- After Alexander's death, Aristotle was obliged to share in the general unpopularity of the Macedonians.
- Charge of impiety.
- He left Athens. He took up his residence at his country house, at Chalcis, in Euboea, and there he died the following year, 322 B.C. His death was due to a disease from which he had long suffered.


Easy online sources:
- Stanford Encyclopedia of Philosophy
- Catholic encyclopedia at New Advent
- Wikipedia


some features of Aristotle’s teaching
- Starts with physics… with the material world we grasp through our external senses;
- Aristotelian Realism;
- Methodology of the Endoxa;
- Physics as the first science;
- Systematic approach;
- Complete approach…


Physics
- Nature as an intrinsic, inner, principle of motion;
- Aristotle’s solution to the Parmenides vs. Heraclitus debate;
- Act and potency (potential);
- Substantial and accidental changes (1+ 9 categories);
- Categories as kinds of beings corresponding to the kinds of motions:
1) Substance;
2) Quantity;
3) Quality;
4) Relation;
5) Place;
6) Time;
7) Position;
8) State;
9) Action;
10) Passion.
- The four causes/principles:
1) Material;
2) Formal;
3) Final;
4) Efficient;
- Hylomorphism;
- Unmoved Mover.


Theory of knowledge
- Sentient knowledge and intellectual knowledge;
- Theory of knowledge, some basic principles:
a) Knowledge as possession of a form;
b) Similarity between the knower (of which the known object is part) and the thing known;
c) Not a destroying change in the knower;
d) Simultaneous actuality of the knowing faculty and the known thing;
e) The act of the known object “as known” and of the act of the knower “as knowing it” are one and the same act;
f) The act of the known object “as known” and of the act of the knower “as knowing it” are one and the same act;
g) This act exists in the knower: i.e., it is an act(ion) of the knower;
h) Knowledge happens according to the mode or essence of the knower;
- The role of the active intellect.


Basic notions in Aristotle’s Logics
- Logic as the last science (maybe not even a science): reducing arguments to their first principles and checking if they have been correctly developed from them;
- Meaning of demonstrating something: premise-conclusion structure;
- Subject of logics: syllogism:
- “A syllogism is speech (logos) in which, certain things having been supposed, something different from those supposed results of necessity because of their being so.” (Prior Analytics I.2, 24b18-20);
- Major premise, minor premise, conclusion: example “All men are mortal; Socrates is a man; Socrates is mortal.”
- Induction and deduction: the need for first (self-evident) premises;