Milesian and Other Presocratic Philosophers Some Presocratics and Theories of the Natural and Metaphysical Worlds

Cosmologies and Mythologies  Mesopotamian Myths of Creation: Marduk (sun) and Tiamat (creative disorder)  Egypt: Nu (water), Aten-Ra (sun), Seth (moon), Nut (heavens)  Egyptian and Mesopotamian astronomical observation: motive seems to be to understand and appease deities  Hesiod Theogony (eighth century BCE): cosmological poem with parallels to Near Eastern creation myths  Greeks: Search for Simple, Universal Laws (Geometric Cosmology)

Nut is often portrayed as a naked female stretched across the sky. The Sun (Ra) is shown entering her mouth, passing through her star speckled body and emerging from her birth canal nine months later (from the spring equinox to the winter solstice). Thus, Ra becomes a self- creating god, i.e. the Universe is self-creating and eternal. Ancient Egypt: Nut and Ra

Egyptian Astronomical Chart Annual Solar Motion of Ra Twelve 30-day months With special 5-day unit To bring total to 365

Babylonian (Mesopotamian) Astronomical Record Arithmetical Calculations Predict Eclipses and Planetary Motion

Greek Debts to Egypt and Mesopotamia  “For the sun-clock and the sundial and the twelve divisions of the day the Greeks learned from the Babylonians” (Herodotus, 2.109)  “When all the discoveries of this kind were fully developed, the sciences which relate neither to pleasure nor yet to the necessities of life were invented, and first in those places where men had leisure. Thus the mathematical sciences originated in the neighborhood of Egypt, because there the priestly class was allowed leisure” (Aristotle, Metaphysics 981b)  Aristotle’s assumption the key: utilitarian vs. free speculation

Greek Debt to Egyptian and Babylonian Science “They did not invent [mathematical science], though they did much to systematize and put it on an exact and universal basis. As in astronomy, they adopted the most valuable achievements of Mesopotamian culture, but developed and indeed transformed them.” (Guthrie, History of Greek Philosophy, vol. 1, pg. 218)

Hesiod, Theogony, “Chaos gave birth to Erebos and black Night; then Erebos mated with Night and made her pregnant and she in turn gave birth to Ether and Day. Gaia now first gave birth to starry Ouranos, her match in size, to encompass all of her, and be the firm seat of all the blessed gods.”

Greek Presocratic Philosophers and Greek Rationalism Underlying Order of Universe can be explained in Mathematical Form

Greek Mainland and Asia Minor Coast

Thales of Miletus  Thales (ca. 620-ca. 550 BCE), possibly of Semitic ancestry (cf. Herodotus, 1.170)  According to Aristotle (Metaphysics, 983b20) the founder of physical science  May have been the founder of Greek geometry, through study and generalization of land measurement  Prime element is Water

Thales’ Theorem a circle is bisected by its diameter, the angles of the base of an isosceles triangle are equal, an inscribed angle in a semicircle is a right angle

Anaximander of Miletus  Anaximander (ca BCE)  Origin of all things is the “Infinite” (to apeiron)  World is product of conflicting opposites which “pay due compensation to each other according to the assessment of Time for their injustice.”  Cosmos ruled by Law  Geocentric Universe: Sun and Moon follow circular orbits around Earth  Invents gnomon for astronomical observation  Draws first map of Earth

Anaximander’s Universe

Anaximenes of Miletus  Anaximenes, flourishes ca. 545 BCE; probable student of Anaximander  Primary element of Cosmos: Air (aether)  Rarified “air” turns to fire, when this is condensed, the results are wind, cloud, water, earth, stone  Theory of rarefaction and condensation: first strictly physical account of relation of things to their primary constituent element

Anaximenes’ Universe

Some Other Presocratic Philosopher s  Parmenides of Elea, ca. 515-after 450 BCE (southern Italy) Ontology (the question of being) Only what is and cannot not be can be known (ungenerated, imperishable, indivisible, motionless, perfect); sensible world therefore is not real  Empedocles of Acragas, ca BCE (Sicily) Real being is permanent, but not motionless and without unity The “All” has four Elements: Earth, Air, Fire, Water Elements acted upon by Strife (Neikos) and Love (Philia) Generation and decay are the compounding and dissolution of the elements through Love and Strife  Heraclitus of Ephesus, flourishes around 500 BCE (Asia Minor) Logos (Reason) as the eternal principle, equated with Fire and the ceaseless conflict of opposites regulated by unchanging Law (Logos)

Elea (Parmenides) and Acragas (Empedocles) Southern Italy and Sicily ELEA ACRAGAS

Parmenides, Empedocles, Heraclitus ParmenidesEmpedocles Heraclitus

Atomists: Motion and Plurality  Leucippus and Democritus (fifth century BCE)  Empty space (denied by Parmenides), the non-existent, separates parts of what does exist from one another  What does exist can be reduced to indivisible units (atoms)  Atoms change position, producing compounds of the changing, sensible world  Both body and soul are arrangements of atoms; death is only a rearrangement and not to be feared  Atomists rescue the world of plurality and motion

Democritus of Abdera (born ca. 460 BCE)

Achievement of Presocratics  Satisfactory explanations of the cosmos must be put on a entirely new footing; mythological explanations are insufficient  Thales may be considered the father of physical science in the western tradition  Parmenides may be considered the father of speculative philosophy and metaphysics in the western tradition  Presocratics’ endeavor was called philosophia > “love of wisdom” > philosophy; their method was logos > “rational account” > logic

Provenances of Presocratics Discussed

Attempting Historical Causal Explanation: Why in these Places at this Time?  Colonies and Contacts (Miletus sent out some 90 colonies according to Pliny the Elder, Natural History 5.112): Relativism and Scepticism  No Sacred Text; Dogma; Priestly Class  Aristocratic Philosophers: scholē and Maslow; non-utilitarian bent of mind  Intellectual Freedom: Source of Philosophy (“love of wisdom”) is curiosity or wonder (Aristotle, Metaphysics 982B12; Plato, Theaetetus 155D)  Caveat: Religious Elements Still Present