Treat with utmost respect your power of forming opinions, for this power alone guards you against making assumptions that are contrary to nature and judgments that overthrow the rule of reason. – Marcus Aurelius
Such as are your habitual thoughts, such also will be the character of your mind; for the soul is dyed by the thoughts. – Marcus Aurelius
He who has seen present things has seen all, both everything which has taken place from all eternity and everything which will be for time without end; for all things are of one kin and of one form. – Marcus Aurelius
The world can doubtless never be well known by theory: practice is absolutely necessary; but surely it is of great use to a young man, before he sets out for that country, full of mazes, windings, and turnings, to have at least a general map of it, made by some experienced traveler. – Lord Chesterfield