Aristotle

1. Aristotle

2. Some Facts about Aristotle • Lived from 384-322 • Plato’s best student at the Academy • Father was a physician—presumably taught Aristotle to examine the natural world for the causes of things • Tutor to the young Alexander the Great • Founded the Lyceum in Athens in 334 • Followers called “Peripatetics” for the peripatoi, or covered walkways (colonnades) in the Lyceum, where they would stroll and philosophize.

3. Some differences between Plato and Aristotle • For Plato, true knowledge does not rely on the senses • For Aristotle, knowledge begins with sense perception • Aristotle is an early empiricist

4. Some differences between Plato and Aristotle • Plato focuses on mathematics as a way to guide people into thinking about philosophy • Aristotle focuses on biologyand physics • Observation,not theory, is the starting point for Aristotle

5. Some differences between Plato and Aristotle • For Plato, the Forms are separately, transcendently existing realities • For Aristotle, forms they do not have a separate existence beyond inhering in specific material things

6. Aristotle’s revision of Plato • For Plato the ever-changing phenomenal world is separate from the true and eternal world of Forms • A thing participates in its eternal Form • Aristotle suggests that the form is found “inside” the phenomena, the universals “inside” the particulars.

7. Aristotle’s revision of Plato • Aristotle thought Plato’s separation of sensible things and their forms to be nonsense. • He called the form of something its essence, that which gives shape, form or purpose to something • The opposite of essence he called matter • Essence without matter is perfect, complete and ideal, but has no substance or solidity (and certainly no independent existence • Matter without essence is formless stuff, not actual but pure potential • Essence “realizes” (makes real) matter.

8. Entelechy: Potentiality becomes Actuality • Aristotle thought that things “participating” in the Forms was insufficient to explain their existence • How did they becomewhat they are? Aristotle believed that nature provided the answer • An acorn becomes an oak over time, but has no choice but to be an oak!(In other words, it cannot be a pine, or a birch) The potential to be an oak is in the acorn, and this potential is actualized when the acorn becomes an oak. • The essence, which exists potentially, of something is actualized in the thing’s matter. • This process of actualization or becoming is called entelechy

9. (Okay, got all that? • (Good, because it gets better) • Aristotle believed that the entelechy of a thing could be explained in four ways • That is, there are four causes of a thing, or four answers to the question, why is a thing what it is? 1.  The material cause: what something is made of. 2.  The formal cause: the thing’s shape, form, or essence; its definition. 3. The efficient cause: the motion or energy that changes matter. 4.  The final cause: its reason, its purpose, the intention behind it. The Four Causes

10. The material cause: the bronze • The formal cause: the shape of the statue the sculptor had in made • The efficient cause: the heat, the forge, the tools, the sculptor • The final cause: to decorate a temple or a palace, to venerate Zeus, to give people something to pray to Statue of Zeus or Poseidon, Athens The Four Causes

11. The Soul • Aristotle’s main work on the soul is De Anima (Latin for Par Psyche, “About the Soul”) • For Aristotle, the soul is the “first entelechy” of the body, the force that moves it to fulfill its potential • The soul animates (gives life to), or realizesa body • Unlike Plato, Aristotle believed the soul and the body cannot exist separately from each other • Unlike Plato, Aristotle did NOT believe in the soul’s immortality. When the body dies, the soul dies.

12. The Soul of a Human • Unlike Plato, Aristotle did not believe in a personal or unique soul. All living things have different souls, but soul does not account for their differences. • LIKE Plato, Aristotle believed in a three-part division of the soul. UNLIKE Plato, Aristotle’s divisions were functional: • The nutritive soul: The souls of all living things (plants, animals, and humans) have this function in common. It is the driving force toward growth • The sensitive soul: Only the souls of animals and humans have this in common. It is the ability to sense one’s surroundings and have feelings • The rational soul: Only humans have this ability to think, reason, and gain abstract knowledge. Only humans can be logical, creative, and imaginative

13. Human Nature • For Plato, a human being is an immortal soul trapped in matter, whose true nature is to be one with the Forms • For Aristotle, a human being is a rational animal, that is, an animal that reasons • For both, REASON is what separates humans from all living things. • Functional argument: • It is the nature of a knife to cut (its final cause), it is proper for a good knife to cut well • It is the nature of a fish to swim, and proper for a good fish to swim well • Just so it is the nature of a human to reason, and proper for a good human to reason well!