Philolaus (Greek: Φιλόλαος; c. 470–c. 385 BCE^[1]) was a Greek Pythagorean and Presocratic philosopher. He argued that all matter is composed of limited and unlimited things, and that the universe is determined by numbers. He is credited with originating the theory that the earth was not the center of the universe. He also thought that the immortal soul was imprisoned as a punishment from former lives.

[edit] Life

Philolaus is variously reported as being born in either Croton,^[2] Tarentum,^[3] or Metapontum.^[4] All three places were located in southern Italy. He may have fled the second burning of the Pythagorean meeting-place around 454 BCE,^[5] after which he migrated to Greece. According to Plato's Phaedo, he was the instructor of Simmias and Cebes at Thebes, around the time the Phaedo takes place, in 399 BCE.^[6] This would make him a contemporary of Socrates, and agrees with the statement that Philolaus and Democritus were contemporaries.^[7] The various reports about his life are scattered among the writings of much later writers and are of dubious value in reconstrucing his life. He apparently lived for some time at Heraclea, where he was the pupil of Aresas, or (as Plutarch calls him) Arcesus.^[8] Diogenes Laërtius is the only authority for the claim that Plato, shortly after the death of Socrates, traveled to Italy where he met with Philolaus and Eurytus.^[9] The pupils of Philolaus and were said to have included Xenophilus, Phanto, Echecrates, Diocles and Polymnastus.^[10] As to his death, Diogenes Laërtius reports a dubious story that Philolaus was put to death at Croton on account of being suspected of wanting to be the tyrant;^[11] a story which Laërtius even took the trouble to put into verse.^[12]

[edit] Writings

Diogenes Laërtius speaks of Philolaus composing one book,^[13] but elsewhere he speaks of three books,^[14] as do Aulus Gellius and Iamblichus. It may have been one treatise, divided into three books. Plato is said to have procured a copy of his book, from which, it was later claimed, Plato composed much of his Timaeus.^[15] One of the works of Philolaus was called On Nature,^[13] which seems to be the same work which Stobaeus calls On the World, and from which he has preserved a series of passages.^[16] Other writers refer to a work entitled Bacchae, which may have been another name for the same work.

[edit] Cosmology

Philolaus did away with the ideas of fixed direction in space, and developed one of the first non-geocentric views of the universe. His new way of thinking quite literally revolved around a hypothetical astronomical object he called the Central Fire.

Philolaus says that there is fire in the middle at the centre ... and again more fire at the highest point and surrounding everything. By nature the middle is first, and around it dance ten divine bodies - the sky, the planets, then the sun, next the moon, next the earth, next the counterearth, and after all of them the fire of the hearth which holds position at the centre. The highest part of the surrounding, where the elements are found in their purity, he calls Olympus; the regions beneath the orbit of Olympus, where are the five planets with the sun and the moon, he calls the world; the part under them, being beneath the moon and around the earth, in which are found generation and change, he calls the sky.

—Stobaeus, i. 22. 1d

A popular misconception about Philolaus is that he supposed that a sphere of the fixed stars, the five planets, the Sun, Moon and Earth, all moved round his Central Fire, but as these made up only nine revolving bodies, he conceived in accordance with his number theory a tenth, which he called Counter-Earth. This fallacy grows largely out of Aristotle's attempt to lampoon his ideas in his book, Metaphysics. In reality, Philolaus' ideas predated the idea of spheres by hundreds of years. He never recognized the fixed stars as any kind of sphere or object.^[17]

His new ideas about the nature of the Earth's place in the cosmos would be influential. Nicolaus Copernicus mentions in De revolutionibus that Philolaus already knew about the Earth's revolution around a central fire.

[edit] Number Theory

Philolaus was deeply involved in the distinctively Pythagorean number theory, dwelling particularly on the properties inherent in the decad – the sum of the first four numbers, consequently the fourth triangular number, the tetractys – which he called great, all-powerful, and all-producing. The great Pythagorean oath was taken by the sacred tetractys. The discovery of the regular solids is attributed to Pythagoras by Eudemus, and Empedocles is stated to have been the first who maintained that there are four classical elements. Philolaus, connecting these ideas, held that the elementary nature of bodies depends on their form, and assigned the tetrahedron to fire, the octahedron to air, the icosahedron to water, and the cube to earth; the dodecahedron he assigned to a fifth element, aether, or, as some think, to the universe. This theory, however superficial from the standpoint of observation, indicates considerable knowledge of geometry and gave a motivating boost to the study of science.

Philolaus argued that all matter is composed of limiters and unlimiteds. Limiters set boundaries, such as shape and quantity. Unlimiteds are universal forms and rules such as the four elements of earth, air, fire and water and the continua of space and time. Limiters and unlimiteds are combined together in a harmony (harmonia), which can be described mathematically (similar to the combinations of elements in modern chemistry). Philolaus used the musical scale to illustrate his philosophy, whereby whole number ratios limit pleasing sounds (e.g., the octave, fifth, and fourth are defined by the ratios 2 : 1, 4 : 3 and 3 : 2).

Following Parmenides' philosophy^{[citation needed]}, Philolaus regarded the soul as a "mixture and harmony" of the bodily parts; he also assumed a substantial soul, whose existence in the body is an exile.

[edit] Notes

[edit] External links

• "Philolaus" article by Carl Huffman in the Stanford Encyclopedia of Philosophy
• Diogenes Laërtius, Life of Philolaus
• Burch, George Bosworth. The Counter-Earth. Osirus, vol. 11. Saint Catherines Press, 1954. p. 267-294