François de la Rochefoucauld (1613-1618) is famous above all for his Maximes (1665), pithy summations of human nature in immortal French prose. He is arguably the greatest French moraliste, meaning someone who describes agreeably but accurately what human beings are like (however sordid that reality may be).
A fairly easy text for practice reading French: a selection of maxims by that king of the form, the 17th-century French moraliste François de La Rochefoucauld (1613-1680). Introduced, glossed, and translated.