Thalès de Milet
The principle of all things is water.
Thalès de Milet (VIIe-VIe s. av. J.-C., Miletus, in Ionia (today in Turkey)) : presocratics. Aristotle presents Thales as the founder of a way of doing philosophy: looking for a single principle from which all things come. For Thales, that principle would be water. On AskPhilosophy: 1 reconstructed argument, 3 quotes checked word for word against the original texts, and 5 common beliefs examined; every text carries an authenticity badge (written by the author, posthumous, student notes, reported, apocryphal).
What do we really know about him?
Almost nothing for certain. Diogenes Laertius (c. 230 AD, about eight centuries later) writes that, according to some, he left nothing in writing, and that the work attributed to him, the Nautical Astronomy, is said to be by Phocus of Samos. Our closest witnesses are Herodotus (c. 440 BC, about a century after his death and a century and a half after the eclipse of 585), Plato (c. 369 BC) and Aristotle (c. 340 BC, about two centuries after his death). Aristotle himself uses "it is said", "he seems", "perhaps". On this site every excerpt carries the badge "transmitted by others" and names who reports it.
Why he matters
Aristotle calls him the "founder" of the philosophy that looks for principles in nature (Metaphysics A 3). Whether or not he really thought what is attributed to him, the question "what does everything come from?", asked without first going through a story of gods (the most common reading, even though Aristotle also credits him with the idea that "all things are full of gods"), stayed attached to his name, and the Milesian thinkers who follow (Anaximander, Anaximenes) answer it in turn. Lists of the Seven Sages almost always include him, but Diogenes Laertius notes that the lists vary from author to author.
A shorter page than the others
We do not fill in the radar axes: no text by Thales tells us whether he believed in God, what we can know, or whether the mind is matter. Each axis is therefore left empty and explains why. None of our questions asks "what is the world made of?": his argument is filed where it fits least badly (see the argument's page).
His positions
click a row to see the evidenceAristotle writes that Thales "perhaps" thought all things are full of gods, because soul would be mixed into the whole universe. Diogenes Laertius, eight centuries later, gives him maxims ("the most ancient of all things is God") which he calls "current", that is, attributed without guarantee. None of this is certainly Thales', and it is neither theism nor atheism. We do not score this axis.
Aristotle supposes that Thales drew his idea from observations (food, heat and seeds are moist), but he says so with "perhaps": this is his reconstruction, not a text by Thales. We do not score this axis.
Diogenes Laertius writes that, according to some, Thales wrote nothing, and according to others he wrote only on the solstice and the equinox, judging the rest unknowable. These are views reported eight centuries later, and they contradict each other. We do not score this axis.
Aristotle ranks Thales among those who see in the soul what sets things in motion: the magnet would have a soul because it moves iron. He writes "he seems" and "to judge from what is recorded". This idea of soul as a moving force does not answer the question materialism or dualism, which the text does not ask. We do not score this axis.
No testimony about free will. The maxims Diogenes Laertius attributes to him ("the strongest is necessity, for it masters all") speak of a general necessity, without discussing our choices. We do not score this axis.
The attributed moral sayings (tl-morale) say nothing about whether good is objective. We do not score this axis.
No text says how Thales understood the relation between believing and reasoning. The reasoning Aristotle attributes to him (starting from observations) is a reconstruction. We do not score this axis.
Diogenes Laertius reports a quip: Thales held that there is no difference between life and death, and asked "why then do you not die?", he answers: "because there is no difference". It is an anecdote, not a doctrine on the meaning of life. We do not score this axis.
No testimony about human nature. We do not score this axis.
Herodotus (about a century later) reports a practical piece of advice from Thales to the Ionians: a common council sitting at Teos, the other cities remaining like districts. It is advice for a situation, not a theory of the individual and the community. We do not score this axis.
Diogenes Laertius gives Thales pieces of practical advice (avoid what you blame in others, do not get rich by shameful means). These are attributed sayings with no theory behind them: no rule, no calculation of consequences, no study of virtues. We do not classify this axis.