Idleness is only the refuge of weak minds.

Let it be your maxim through life, to know all you can know, yourself; and never to trust implicitly to the information of others.

Cultivate the habit of thinking ahead, and of anticipating the necessary and immediate consequences of all your actions.... Likewise in your pleasures, ask yourself what such and such an amusement leads to, as it is essential to have an objective in everything you do. Any pastime that contributes nothing to bodily strength or to mental alertness is a totally ridiculous, not to say, idiotic, pleasure.

The only sure way of avoiding these evils [vanity and boasting] is never to speak of yourself at all. But when, historically, youare obliged to mention yourself, take care not to drop one single word that can directly or indirectly be construed as fishing for applause.

Speak the language of the company you are in; speak it purely, and unlarded with any other.

There is nothing so necessary, but at the same time there is nothing more difficult (I know it by experience) for you young fellows, than to know how to behave yourselves prudently towards those whom you do not like. Your passions are warm, and your heads are light; you hate all those who oppose your views, either of ambition or love; and a rival, in either, is almost a synonymous term for any enemy.

Buy good books, and read them; the best books are the commonest, and the last editions are always the best, if the editors are not blockheads.