This collection includes most of the purely philosophical (without admixture of politics) treatises of Cicero, the texts of which, fortunately for us, have been preserved in whole or with very small omissions. Written in the traditional form of dialogues or collections of letters for Antiquity (the conditional "addressee" of which in this case is the son of Cicero Mark), they fully express the unbending, almost Puritan moral and ethical principles of the author - the first in the galaxy of great geniuses of the Roman Stoic tradition, which continued and largely changed Stoicism Greek.