# Thales

Thales (Θαλῆς; c. 624 BC – c. 546 BC) was a philosopher born in Tyre, South of Lebanon and one of the Seven Sages of Greece. He has been called the "father of science."

## Quotes

* παντα πληρη θεων ειναι
** Panta plêrê theôn einai.
** All things are full of gods.
** As quoted in Aristotle, De Anima, 411a
* Water is the first principle of everything.
** As quoted in Aristotle, Metaphysics, 983b
* Σοφώτατον χρόνος· ἀνευρίσκει γὰρ πάντα.
** Time is the wisest of all things that are; for it brings everything to light.
** As quoted in Diogenes Laërtius, The Lives and Opinions of Eminent Philosophers, I, 35
* Οὔ τι τὰ πολλὰ ἔπη φρονίμην ἀπεφήνατο δόξαν
** A multitude of words is no proof of a prudent mind.
** As quoted in Diogenes Laërtius, The Lives and Opinions of Eminent Philosophers, I, 35; as translated in Dictionary of Quotations (Classical) edited by Thomas Benfield Harbottle, p. 455
** Also translated as: "Many words do not declare an understanding heart."
* Ἐὰν ἃ τοῖς ἄλλοις ἐπιτιμῶμεν, αὐτοὶ μὴ δρῶμεν
** Avoid doing what you would blame others for doing.
** As quoted in Diogenes Laërtius, The Lives and Opinions of Eminent Philosophers, I, 36
** Cf. Golden Rule
* Μέγιστον τόπος· ἅπαντα γὰρ χωρεῖ
** Place is the greatest thing, as it contains all things.
*** As quoted in Diogenes Laërtius, The Lives and Opinions of Eminent Philosophers, I, 35
* Γνῶθι σαυτόν
** Know thyself.
** As quoted in Diogenes Laërtius, The Lives and Opinions of Eminent Philosophers, I, 40
** Variant:
** The most difficult thing in life is to know yourself.
*** Many Thoughts of Many Minds (1862), by Henry Southgate, p. 338
** Cf. Plato, Charmides 164: "τὸ γὰρ Γνῶθι σαυτόν καὶ τὸ Σωφρόνει ἔστιν μὲν ταὐτόν".
* Hope is the only good that is common to all men; those who have nothing else possess hope still.
** A Dictionary of Thoughts (1908) by Tryon Edwards, p. 234
* Placing your stick at the end of the shadow of the pyramid, you made by the sun's rays two triangles, and so proved that the pyramid [height] was to the stick [height] as the shadow of the pyramid to the shadow of the stick.
** W. W. Rouse Ball, A Short Account of the History of Mathematics (1893, 1925)
* Do not ask who started it. Finish it
** A Dictionary of Thoughts (1908) by Tryon Edwards, p. 234
* Nothing is more ancient than God, for He was never created; nothing more beautiful than the world, it is the work of that same God; nothing is more active than thought, for it flies over the whole universe; nothing is stronger than necessity, for all must submit to it.
** As quoted in Love and Live Or Kill and Die: Realities of the Destruction of Human Life (2009) by James H. Wilson, p. 72
** Variants:
** Strongest is Necessity because it governs all things.
*** As quoted in Symbolism of the Sphere: A Contribution to the History of Earlier Greek Philosophy (1977), by Otto Brendel p. 36
** Nothing is more active than thought, for it travels over the universe, and nothing is stronger than necessity for all must submit to it.
*** As quoted in Business Management Controls: A Guide (2012) by John Kyriazoglou, p. 55

## Quotes about Thales

* Thales asserted Water to be the principle of things. For he saw that matter was principally dispensed in moisture, and moisture in water; and it seemed proper to make that the principle of things, in which the virtues and powers of beings, and especially the elements of their generations and restorations, were chiefly found. He saw that the breeding of animals is in moisture ; that the seeds and kernels of plants (as long as they are productive and fresh), are likewise soft and tender; that metals also melt and become fluid, and are as it were concrete juices of the earth, or rather a kind of mineral waters; that the earth itself is fertilised and revived by showers or irrigation, and that earth and mud seem nothing else than the lees and sediment of water; that air most plainly is but the exhalation and expansion of water; nay, that even fire itself cannot be lighted, nor kept in and fed, except with moisture and by means of moisture. He saw, too, that the fatness which belongs to moisture, and which is the support and life of flame and fire, seems a kind of ripeness and concoction of the water.
** Francis Bacon, De Principiis Atque Originibus as translated in The Philosophical Works of Francis Bacon (1905) edited by John M. Robertson
* Thales had a motto — sophotaton chronos aneuriskei gar panta — which means time is wisest because it discovers everything. We still live by that motto — we mark the time and aid the discoveries by keeping the soul lines intact.
** Dennis Batchelder, Soul Identity (2007), p. 59
* It seems probable that the early Greeks were largely indebted to the Phoenicians for their knowledge of practical arithmetic or the art of calculation, and perhaps also learnt from them a few properties of numbers. It may be worthy of note that Pythagoras was a Phoenician; and according to Herodotus, but this is more doubtful, Thales was also of that race.
** W. W. Rouse Ball, A Short Account of the History of Mathematics (1905)
* It has fallen to the lot of one people, the ancient Greeks, to endow human thought with two outlooks on the universe neither of which has blurred appreciably in more than two thousand years. ...The first was the explicit recognition that proof by deductive reasoning offers a foundation for the structure of number and form. The second was the daring conjecture that nature can be understood by human beings through mathematics, and that mathematics is the language most adequate for idealizing the complexity of nature into appreciable simplicity. Both are attributed by persistent Greek tradition to Pythagoras in the sixth century before Christ. ...there is an equally persistent tradition that it was Thales... who first proved a theorem in geometry. But there seems to be no claim that Thales... proposed the inerrant tactic of definitions, postulates, deductive proof, theorem as a universal method in mathematics. ...in attributing any specific advance to Pythagoras himself, it must be remembered that the Pythagorean brotherhood was one of the world's earliest unpriestly cooperative scientific societies, if not the first, and that its members assigned the common work of all by mutual consent to their master.
** Eric Temple Bell, The Development of Mathematics (1940)
* It was not Zeno, the founder of the Stoics, alone, who taught that the Universe evolves, and its primary substance is transformed from the state of fire into that of air, then into that of water, etc. Heraclitus of Ephesus maintained that the one principle that underlies all phenomena in Nature is fire. The intelligence that moves the Universe is fire, and fire is intelligence. And while Anaximenes said the same of air, and Thales of Miletus (600 years b.c.) of water, the Esoteric Doctrine reconciles all these philosophers, by showing that though each was right, the system of none was complete.
** H.P. Blavatsky, The Secret Doctrine, Vol. 1 of 4 (1888)
* With regard to the Pythagorean theorem my conjecture is that... it was known to Thales. ...the hypotenuse theorem is a direct consequence of the principle of similitude, and... Thales was fully conversant with the theory of similar triangles.
** Tobias Dantzig, The Bequest of the Greeks (1955)
* The more one studies the period of Thales—the more one compares the knowledge he bequeathed to prosterity with the one he had found when he began his work—the more does his mathematical stature grow, until one is impelled to range Thales with such figures as Archimedes, Fermat, Newton, Gauss and Poincaré.
** Tobias Dantzig, The Bequest of the Greeks (1955)
* Thales the teacher produced the first geometers, even as Thales the thinker founded the first geometry worthy of the name.
** Tobias Dantzig, The Bequest of the Greeks (1955)
* [W]ith Thales... Aristotle ascribes the statement: "Water is the material cause of all things." This... expresses, as Nietzsche... pointed out, three fundamental ideas of philosophy. First, ...the material cause of all things; second, ...that this ...be answered in conformity with reason, without ...myths or mysticism; third, ...that ...it must be possible to reduce everything to one principle.
** Werner Heisenberg, Physics and Philosophy (1958) pp. 59-60.
* Thales' statement was the first expression of... a fundamental substance, of which all other things were transient forms. The word "substance"... was... not interpreted in the purely material sense ...Aristotle ascribes to Thales also ...All things are full of gods. ...[We can] imagine ...Thales took his view ...from meteorological considerations. ...[W]ater can take the most various shapes... ice and snow... vapor, and... clouds. It seems to turn into earth where the rivers form their delta, and it can spring from the earth. Water is the condition for life. Therefore... [as] a fundamental substance, it was natural to think of water first.
** Werner Heisenberg, Physics and Philosophy (1958) p. 60.
* Since Alyattes would not give up the Scythians to Cyaxares at his demand, there was war [ Battle of Halys ] between the Lydians and the Medes for five years; each won many victories over the other, and once they fought a battle by night. They were still warring with equal success, when it happened, at an encounter which occurred in the sixth year, that during the battle the day was suddenly turned to night. Thales of Miletus had foretold this loss of daylight to the Ionians, fixing it within the year in which the change did indeed happen.
** Herodotus, Histories, 1.74 (c. 440 BC)
* It has been asserted that metaphysical speculation is a thing of the past and that physical science has extirpated it. The discussion of the categories of existence, however, does not appear to be in danger of coming to an end in our time, and the exercise of speculation continues as fascinating to every fresh mind as it was in the days of Thales.
** James Clerk Maxwell, "Introductory Lecture on Experimental Physics," The Scientific Papers of James Clerk Maxwell (1890), Vol.2
* While [Thales] was studying the stars and looking upwards, he fell into a pit, and a neat, witty Thracian servant girl jeered at him, they say, because he was so eager to know the things in the sky that he could not see what was there before him at his very feet.
** Plato, Theaetetus, 174a (trans. H. N. Fowler)
* [Thales] first went to Egypt and hence introduced this study [geometry] into Greece. He discovered many propositions himself, and instructed his successors in the principles underlying many others, his method of attack being in some cases more general [i.e. more theoretical or scientific], in others more empirical [...more in the nature of simple inspection or observation].
** Proclus, A Commentary on the First Book of Eudlid's Elements (c. 450 AD), as quoted by Thomas Little Heath, A History of Greek Mathematics (1921) Vol. 1, p. 128, citing Proclus on Eucl. I, p. 65. 7–11.
* In committing himself to a form of materialism, Thales rejects a picture of the universe found in the Homeric poems, one which posits, in addition to the natural world, a supernatural quadrant populated by beings who are not subject to such laws as may govern the interactions of all natural bodies. If all things are composed of matter, then it ought to be possible to explain all there is to explain about the universe in terms of material bodies and their law-governed interactions. This simple thought already stands in sharp contrast to a world supposed to be populated by supernatural immaterial beings whose actions may be capricious or deliberate, rational or irrational, welcome or unwelcome, but which as a matter of basic principle cannot be explicated in terms of the forms of regularity found in the natural world. In Thales’ naturalistic universe, it ought to be possible to uncover patterns and laws and to use such laws as the basis for stable predictions about the direction the universe is to take; to uncover causes and to use that knowledge to find cures for illnesses or to develop strategies for optimizing our well-being; and, less practically, to find broad-based explanations to fundamental questions which crop up in every organized society. Such questions persist: Where did the universe come from? What, ultimately, is its basic stuff?
** Christopher Shields, Ancient Philosophy: A Contemporary Introduction (2nd ed., 2011), p. 2
* According to tradition, Thales is the first to reveal the study of nature to the Greeks; although he had many predecessors, in Theopharastus' view, he so surpassed them as to eclipse everyone before him.
** Simplicius, Physics, 23.29–33

## See also

* Ancient Greek mathematics
* Geometry
* History of mathematics

## External links

* Thales of Miletus from The Internet Encyclopedia of Philosophy
* Thales of Miletus from the MacTutor History of Mathematics archive
* Livius, Thales of Miletus by Jona Lendering
* Thales profile
* Thales' Theorem - Math Open Reference
* Thales biography by Charlene Douglass
Ancient Greek schools of philosophy :
| Pre-Socratic | Anaxagoras • Anaximander • Anaximenes • Democritus • Empedocles • Heraclitus • Leucippus • Melissus • Parmenides • Protagoras • Pythagoras • Thales • Zeno of Elea |
| Socratic | Antisthenes • Aristippus • Aristotle • Diogenes of Sinope • Euclid of Megara • Phaedo of Elis • Plato • Socrates |
| Hellenistic | Apollonius of Tyana • Augustine • Epictetus • Epicurus • John Philoponus • Lucretius • Plotinus • Proclus • Pyrrho • Sextus Empiricus • Zeno of Citium |
Mathematics :
| Mathematicians (by country) | Abel • Anaxagoras • Archimedes • Aristarchus of Samos • Averroes • Arnold • Banach • Cantor • Cartan • Chern • Cohen • Descartes • Diophantus • Erdős • Euclid • Euler • Fourier • Gauss • Gödel • Grassmann • Grothendieck • Hamilton • Hilbert • Hypatia • Lagrange • Laplace • Leibniz • Milnor • Newton • von Neumann • Noether • Penrose • Perelman • Poincaré • Pólya • Pythagoras • Riemann • Russell • Schwartz • Serre • Tao • Tarski • Thales • Turing • Weil • Weyl • Wiles • Witten |
| Numbers | 1 • 23 • 360 • e • π • Fibonacci numbers • Irrational number • Negative number • Number • Prime number • Quaternion • Octonion |
| Concepts | Abstraction • Algorithms • Axiomatic system • Completeness • Deductive reasoning • Differential equation • Dimension • Ellipse • Elliptic curve • Exponential growth • Infinity • Integration • Geodesic • Induction • Proof • Partial differential equation • Principle of least action • Prisoner's dilemma • Probability • Randomness • Theorem • Topological space • Wave equation |
| Results | Euler's identity • Fermat's Last Theorem |
| Pure math | Abstract algebra • Algebra • Analysis • Algebraic geometry (Sheaf theory) • Algebraic topology • Arithmetic • Calculus • Category theory • Combinatorics • Commutative algebra • Complex analysis • Differential calculus • Differential geometry • Differential topology • Ergodic theory • Foundations of mathematics • Functional analysis • Game theory • Geometry • Global analysis • Graph theory • Group theory • Harmonic analysis • Homological algebra • Invariant theory • Logic • Non-Euclidean geometry • Nonstandard analysis • Number theory • Numerical analysis • Operations research • Representation theory • Ring theory • Set theory • Sheaf theory • Statistics • Symplectic geometry • Topology |
| Applied math | Computational fluid dynamics • Econometrics • Fluid mechanics • Mathematical physics • Science |
| History of math | Ancient Greek mathematics • Euclid's Elements • History of algebra • History of calculus • History of logarithms • Indian mathematics • Principia Mathematica |
| Other | Mathematics and mysticism • Mathematics education • Mathematics, from the points of view of the Mathematician and of the Physicist • Philosophy of mathematics • Unification in science and mathematics |
* ↑ Singer, Charles (2013) A Short History of Science to the Nineteenth Century