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Thales of Miletus

all matter is a form of water


student of Thales; all matter is a form of apeiron ("the boundless")


all matter is a form of air


established school in Crotona Italy; emphasized myths, reincarnation, musical pitch, and math

Heraclitus of Ephesus

all matter made of fire; only reality is the law of change, Logos


established school in Elea Italy; emphasized unchanging universe; "being is"

Zeno of Elea

student of Parmenides; introduced four logical paradoxes to prove the unity of being


proposed the four elements of air, water, earth, and fire and the two forces of love and strife; eternal cycle of chaos


all matter is composed of tiny seeds; proposed cosmic evolution


student of Leucippus; proposed atomic theory and deterministic materialism


"Man is the measure of all things"; natural science and religion are worthless; one should only be ethical if it is to his advantage; sophists were known as deceitful and insincere


sentenced to death 399 BC; refused payment for his lectures; held that all people have full knowledge of ultimate truth; Socrates' paradox: no man does evil voluntarily


student of Socrates; recorded Socrates' teachings in his dialogues; virtue = wisdom; proposed theory of Ideas, doctrine of Forms, the intelligible and sensible realms, and the Absolute Idea of the Good; wrote the Republic (discussion of justice), Meno (Socrates shows innate knowledge of all people by teaching a slave the Pythagorean theorem), Apology (Socrates' trial defense), Crito (Socrates' defense of obedience to the state), Phaedo (death of Socrates), Symposium (a drama), Parmenides (theory of Forms), Laws (political discussions), Timaeus (thoughts on cosmology and science)


student of Plato; tutor to Alexander the Great; founded Lyceum and Peripatetic ("walking") school; founded logic, syllogism, scientific method; forms contained in objects; natural hierarchical order of inanimate, vegetative, animal, rational, and heavenly ether; emphasized happiness; wise king best government but limited democracy a good compromise; wrote Organon ("instrument" logic), Physics, Metaphysics, Poetics (literary criticism, definitions of drama)

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