Oct 4 LecturePresocratic philosophers: new questions and answers about the world, 600-399BCE
Greek timeline
1500-1200BCE Mycenaean/Heroic
1200-700 Dark Age
700-500 Archaic age
500-300 Classical Greece (Hellenic)
Presocratics, Socrates, Plato, Aristotle
Greek mythology
Flexible religious beliefs.
Public displays.
Gods anthropomorphic, yet also embody forces of nature (Gaia = mother nature; Zeus = sky, thunder…).
Gods could account for natural phenomena (volcano, eclipse…).
Myths mainly relevant to human affairs & morals; less about nature.
Greek myth of Prometheus’s creation of humans
Prometheus [Titan] molded men out of water and earth and gave them also fire, which, unknown to Zeus, he had hidden in a stalk of fennel. But when Zeus learned of it, he ordered Hephaestus to nail his body to MountCaucasus. On it Prometheus was nailed and kept bound for many years. Every day an eagle swooped on him and devoured his liver, which grew by night. That was the penalty that Prometheus paid for the theft of fire until Heracles [Hercules] released him.
Rational rejection of myths?
Historians
Herodotus (484-420) includes divine meddling in human affairs to explain historical episodes.
Thucydides (455-400) rationalist, no divine accounts. Sifts evidence to find most likely events & motives.
New science & old religious myth coexist
Presocratic philosophers 600-399BCE (death of Socrates)
First “serious, critical inquiry” into nature.
Naturalistic, materialist causes of phenomena.
Exclude supernatural explanations (traditional myths, religious beliefs).
No divine plan, design of world.
Where they came from: Greek colonies 500BCE, expansion & warfare
Ionia (Asia Minor)
Persian Wars 500BCE-
Persians invade Ionia, eastern Aegean, longtime Greek colonies
Athens defends the colonies
Sometime alliances with Sparta
Battles eg Marathon
Naval power
The Ionian Thinkers
Thales 585BCE
Anaximander 550
Anaximenes 550
Pythagoras 530
Heraclitus 500
Leucippus 440
Presocratics in Greek city-states in Italy
Pythagorean school 500
Parmenides 480
Zeno 450
Empedocles 450
What did these philosophers want to know?
Philosophy = love of wisdom
Physis = nature
Cosmos = world that is orderly and beautiful (cosmetic). How did order, regularity emerge out of original chaos?
What do we know about the Presocratics?
Surviving sources = fragments of their writing or ideas cited in later authors such as Plato and Aristotle. No primary texts.
Quoted in order to be refuted = 300 year dialogue between thinkers.
Trustworthy sources?
Specific Presocratic topics of inquiry
1. What is the origin of the world.
2. What is the underlying reality of the world.
3. Is there change in the world, what kind.
4. Reliability of the senses: how can we know about the world.
= Set the philosophical agenda for Western science.
Thales of Miletus
Everything is made of water.
Unseen material substratum
Fits observations of water everywhere
Maybe related to origin myths of Near East
Also said earth is a disk floating on water
Thales as “scientist”
Materialist view, no supernatural.
Reality is more than just appearances.
Searching for how/why, hidden causes, orderliness.
Non-practical knowledge, for its own sake.
Anaximander
Cosmogony (origins): The world originated when a “seed” that could “produce hot & cold” separated out of “the infinite and eternal” primayr stuff.
A sphere of flames around the earth divided to become sun, moon, stars.
more Anaximander (cosmology)
Stars, sun, moon are wheels of air filled with fire. Flames can be seen thru openings. Eclipse is a blockage.
Earth floats in the middle of the universe; unsupported; same distance from everything.
Earth’s shape is cylindrical (like drum, pillar); we live on one of the flat end surfaces.
last Anaximander (earth phenomena)
Thunder, lightening, rain have physical causes.
Living things arose from mud when evaporated by the sun. All animals including man originated as fish covered with thorns. Over time they emerged onto dry land and changed their habits.
= Attempts at rational explanations; often gives his reasoning; entirely naturalistic.
Atomists 450BCE: Leucippus, Democritus
What is the world made of?
Atom = unit which cannot be divided.
Underlying structure of matter is minute indivisible atoms, moving randomly and constantly in an infinite void.
Everything explainable by the sizes and motions of these particles. Collide, combine.
Materialist universe; no supernatural.
Atoms not knowable by sense perceptions.
Can change occur in nature?
If underlying reality is an unchanging element such as water, then can changes occur in visible reality?
Can something come into being from nothing?
Change
Heraclitus says change is constant and real; can’t step into same river twice.
Parmenides and Zeno say NO change really occurs; change is logically impossible.
Therefore our senses deceive us.
Valid knowledge comes from reasoning.
Empedocles
Everything made of 4 elements:
Earth, water, air, fire
Change = “mingling & mixing of parts”
To generate things, elements are combined or separated by the immaterial forces “love and strife.”
Plants and animals arose by material causes during a period of love:
Empedocles’ random biology
“First detached limbs are formed from the elements; these limbs join together in chance combinations to form monsters such as ‘manfaced oxkind’ and ‘oxheaded mankind.’ Unable to survive, these monsters perish. But when limbs come together in viable combinations, the resulting beasts survive and reproduce.”
Why was “science” born in Classical Greece, esp Athens?
Lindberg (p. 11)
Mythologies “as long as effective, there is no reason to question them. There are no rewards for skepticism and few resources to facilitate challenge.”
So what happened?
Classical age, Athens 500-300BCE
Cultural center of Greek world.
Political democracy.
Leading philosophers
Socrates
Plato
Aristotle
Athenian domestic & foreign policies
Autonomous city-state (polis)
Population 300,000
50,000 male voters
100,000 slaves
Imperialist expansion, warfare.
Dominant power along with Sparta (until Alexander)
Athenian democracy introduced by Pericles 460BCE
Assembly = all adult free males. Direct, radical democracy.
“Who wishes to speak to the Assembly?
Council = random representatives who implement decisions.
Pericles:“The worst thing is to rush into action before consequences have been properly debated.”
Parallel between Greek democracy and philosophy: politics influences science?
Historian G.E.R. Lloyd (1979) Magic, Reason, and Experience
Critical debate and thinking
Best solutions
“Just as one of the notable features of Greek political experience is the way in which questions about how society should be regulated came to be a subject for open discussion, so too the possibility of challenging deeply held assumptions about ‘nature’ and of debating such issues as the origin of the world is a prominent characteristic of Greek speculative thought.” (Lloyd)
“Testing arguments, weighing evidence, and adjudicating between opposing points of view were a common part of the experience of a considerable number of Athenian citizens.”
Political/legal debate as “contest”
Skill at rhetoric = argument
Rhetoric gets at truth??
Aristotle
“It is through wonder that men began to philosophize; wondering in the first place about obvious perplexities, and then raising questions about greater matters too, eg the motions of sun and stars and origin of the universe. The myth-lover is in a sense a philosopher since myths are composed of wonders; therefore if it was to escape ignorance that men studied philosophy, it is obvious that they pursued science for the sake of knowledge, and not for any practical utility.” (Metaphysics)