...There are some, both at present and of old, who recognized that Spartanizing is much more a love of wisdom than a love of physical exercise, knowing that the ability to utter such [brief and terse] remarks belongs to a perfectly educated man. Among these were Thales of Miletus, and Pittacus of Mytilene, and Bias of Priene, and our own Solon, and Cleobulus of Lindus, and Myson of Chen, and the seventh of them was said to be Chilon of Sparta. They all emulated and admired and were students of Spartan education, and one could tell their wisdom was of this sort by the brief but memorable remarks they each uttered when they met and jointly dedicated the first fruits of their wisdom to Apollo in his shrine at Delphi, writing what is on every man's lips: Know thyself, and Nothing too much. Why do I say this? Because this was the manner of philosophy among the ancients, a kind of laconic brevity.
The passage in which the above occurs is "elaborately ironical"; so it is tough to know which aspects of it to take seriously, though Diogenes Laertius later confirms that there were indeed seven such individuals who were held in high esteem for their wisdom well before Plato's time. Diogenes introduces a similar list with the words "These men are acknowledged wise"; however, on Diogenes' first list of seven, Periander appears instead of Myson. According to Diogenes, citing Demetrius Phalereus, it was during the archonship of Damasias (582/1 B.C.) that the seven had first become known as "the wise men", Thales being the first so acknowledged. Diogenes points out that there was, among his sources, great disagreement over which figures should be counted among the seven, and even that there was disagreement over the number of sages, some lists including up to seventeen individuals.
Later tradition ascribed to each sage a pithy saying of his own, but ancient as well as modern scholars have doubted the legitimacy of such ascriptions. According to one pair of scholars, "The actual authorship of the...maxims set up on the Delphian temple may be left uncertain. Most likely they were popular proverbs, which tended later to be attributed to particular sages.
In addition to being credited for pithy sayings, the wise men were also apparently famed for practical inventions; in Plato's Republic (600a), it is said that it "befits a wise man" to have "many inventions and useful devices in the crafts or sciences" attributed to him, citing Thales and Anacharsis the Scythian as examples. (Some sources include Anacharsis among the Seven Sages.)
According to a number of fictitious stories, there was a golden tripod (or, in some versions of the story, a bowl or cup) which was to be given to the wisest. Allegedly, it passed in turn from one of the seven sages to another, beginning with Thales, until one of them (either Thales or Solon, depending on the story) finally dedicated it to Apollo who was held to be wisest of all.
According to Diogenes, Dicaearchus claimed that the Seven "were neither wise men nor philosophers, but merely shrewd men, who had studied legislation. And according to at least one modern scholar, the claim is correct: "With the exception of Thales, no one whose life is contained in [Diogenes'] Book I [i.e. none of the above] has any claim to be styled a philosopher.