(from Kirk and Raven)
Traditionally regarded as the earliest physicist -- i.e., the first inquirer into the nature of things as a whole. [For the Greeks, Thales is the father of the systematic study of nature, of physis.]
Accomplishments:
Predicted an eclipse which took place in 585 B.C.E. [Probably based on access to Babylonian [Mesopotamia] records, which were begun in 721 B.C.E. It is from here that Thales learned of the Saronic cycle -- 18 years, 11 and 1/3rd days -- which Babylonian observation had shown to be usual between eclipses of the sun. This allowed him to make a "lucky" forecast of the eclipse visible at Miletus in 585 B.C.E.]
Advised the Ionians to have a single deliberative chamber in Teos, in the middle of Ionia ["POLITICS"]
While in the army, diverted a river in order to facilitate crossing.
Tradition has it that he visited Egypt [and Mesopotamia]. It is customary to credit 6th ct. sages -- e.g., Solon -- with visits to Egypt, the traditional source of Greek science. In fact:
Thales, as the first Greek geometer, had good reason for association with the home of land measurement;In some Egyptian myths, water plays an essential part. Thales' idea that the earth floats on water is probably derived from earlier near-eastern, possibly Egyptian myth.
Thales did develop a "theory" about the flooding of the Nile.
Anecdotes: story of falling into the well; cornering the market on wine-presses.
method for measuring the height of a pyramid (at the time when a person's shadow = his height)
"geometry" (K&R, 84) [Geometry for the Greeks evidently derived from the Egyptians, who had particular insights {e.g., the square of the hypotenuse of a right-angled triangle = the sum of the squares of the other two sides: but this holds only for specific cases, e.g., 3,4,5}.
Thales generalized these special cases, and in this sense is the father of mathematics as a science, e.g.
angles at the base of an isosceles triangle are equalthe two sides of an isosceles triangle are equal when two straight lines intersect, opposite angles are equal
the angle on the circumference of a circle subtended by the diameter is always a right angle
the sum of the angles of a triangle = 2 rights angles
the sides of triangles with equal angles are always proportional.
Simple applications:
1) Using the principle of similar triangles: measuring the distance from shore to ship at sea2) Measure the height of a pyramid by comparing the length of its shadow with that cast by an object of known height.
Probably left no writings of his own; our knowledge of his thought depends almost entirely on Aristotle (De Caelo B 13, 294a28; Met A3, 983b6).
Summary of "thought":
Thales is at least as significant for the shape of his project as he is for his actual philosophical (as well as political and mathematical) accomplishments. "ultimate object was to find a formula for all things"
the earth rests on water;
[this is similar to myth, in that:
something is accounted for in terms of its origin;the diversity of things is seen to derive from a unitary source --
THERE IS HERE A VISION OF THE UNIVERSE WHICH AFFIRMS BOTH ITS DIVERSITY AND ITS ORIGIN-AL UNITY:
THINGS ARE RELATED.
but: water is a "secular," material stuff -- not a supernatural force. THERE IS HERE A MATERIALIST THEORY.]
the principles (arche) are matter -- a substance from which all things come to be and into which they are finally destroyed: hence there is no absolute coming to be/passing away -- for the substance or nature is always preserved.
Thales claims it is water. Aristotle (the biologist) argues that this is because "the nurture of all things is moist," and the seeds of all things have a moist nature. (K&R, 87)
Even apparently inanimate things can be alive: "the world is full of gods." Aristotle (de Anima A2, 405a19): Thales seems to have supposed that the soul was something kinetic, if he said that the (Magnesian) stone possesses soul because it moves iron. (In other terms, there is here an assumed analogy between the human and the natural.)
Diogenius L. -- magnet & amber
"Thales appears to have made explicit, in an extreme form, a way of thinking that permeated Greek mythology, but whose ultimate origins were almost prearticulate." (K&R, 95)
cf. Buddhism, Amerindians: "Animism" -- the world is permeated by a life-force (psyche) which is divine. ["arises out of the failure to objectify one's experience of the outside world, a technique which requires some practice."]
--> cf. the critique that Western knowledge, as based on a sundering of self//world [based in turn on the model of "seeing" as a model of knowledge] issues more readily into master/slave relations.
In any case, any connection between such animism and water is not clear.
[At least of equal importance to this new way of seeing the world is Thales' enumerating in his mathematical work something like "natural laws" -- i.e., generalizations.]