Teaching By Examples

I have read somewhere or other -- in Dionysius of Halicarnassus, I think -- that history is philosophy teaching by examples.

-- Henry St John, 1st Viscount Bolingbroke (1678 - 1751), English statesman and philosopher, On the Study and Use of History, letter 2; in fact this relates to a third-century AD treatise on rhetoric, wrongly attributed to Dionysius of Halicarnassus, which says (xi. 2): "The contact with manners then is education; and this Thucydides appears to assert when he says history is philosophy learned from examples".  The line is not found in Thucydides