Kathleen Norton
April 15, 1995
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Thales of Miletus was a statesman, engineer, astronomer, mathematician and a philosopher. Such activity in varied fields was not uncommon among academics in ancient Greece. However, according to Plutarch, "Thales was the only wise man of the time who carried his speculations beyond the realm of the practical (Solon 3.4)." Because Thales did not always seek answers to practical questions, he was seen by some people as "wise but not prudent." One tale by Plato describes Thales falling into a well because he was too busy examining the stars above.
However, this seemingly imprudent observation of the stars did lead to practical applications in navigation. Thales "measured out the little stars of the Wain, by which the Phoenicians sail (Callimachus Iambus I, 52 in Kirk, Raven and Schofield)." Thales defended the practicality of philosophy by using his knowledge to predict a bumper crop of olives and to then possess a monopoly of olive presses.
Despite some criticism, Thales was highly regarded. He was one of the Seven Wise Men who, according to Pausinias, authored the "maxims useful for the life of men (10.24.1)" inscribed on the temple at Delphi. These maxims, such as "know thyself" and "nothing overmuch," were used by Plato to argue that Thales and the other Seven Wise Men were enthusiasts of the Spartan culture.
Another example of contemporary opinion of Thales occurs in Plutarch's Solon 4.3. According to Plutarch, the Coans found a tripod said to have belonged to Helen of Troy in their fishing nets. The Pythian Priestess of Apollo told them to give the tripod to the wisest man. The tripod was given to Thales.
Not all of Thales' ideas were original. Thales spent a considerable amount of time travelling and was thought to have been involved with trade. It is thought that while travelling Thales gathered knowledge and brought it back to the Greek world. For instance, Thales is said to have predicted the eclipse in 585. This prediction was likely based on research conducted by Babylonian priests.
The geometric theories proposed by Thales may have been derived from Egypt. These theories are important because they formed a foundation for Greek math. Thales demonstrated that: 1) a circle is bisected by diameter, 2) the base angles of an isosceles triangle are equal, 3)that opposite angles are equal and 4) that corresponding angles in a triangle have proportional sides. Use of the fourth theorem made estimating distances possible.
Foreign influence is also evident in Thales' cosmology. He believed that the earth floats on water, which is similar to the Eqyptian idea of a flat earth resting on water. Thales also believed that everything originates from water. Though Thales believed that all things were "full of gods (Aristotle de anima A5, 411a7 in Kirk, Raven and Schofield)," his cosmology was the first to depart from the idea that gods are responsible for the origin of life. This departure reflects a step in the development of science as it is necessary to separate the natural from the supernatural when conducting scientific inquiries.
Thales' idea of water as the principle matter was later criticized by Anaximander (c. 550). Anaximander did not think water could be the source for all things since water destroys fire. Anaximedes (c. 525) also disagreed with Thales' cosmology. Instead of water, Anaximedes argued that air is earth's primary component.
Despite contemporary criticisms and differing opinions by later philosophers, Thales remains an important pre-Socratic philosopher. Thales contributed important mathematical and astronomical theorems and was a pioneer in the field of natural philosophy.
References
Kirk, Raven and Schofield. The Presocratic Philosophers. Cambridge University
Press. Great Britain. 1983.
Perseus HomePage. English Texts. Tufts University.