Seneca

Nature does not reveal her mysteries once and for all.

Believe me if you consult philosophy she will persuade you not to lit so long at your counting desk.

Pain is slight if opinion has added nothing to it; ... In thinking it slight, you will make it slight. Everything depends on opinion. It is according to opinion that we suffer. A man is as wretched as he has convinced himself that he is.

Man is a social animal.

Timendi causa est nescire - Ignorance is the cause of fear.

They laboriously do nothing.

It takes all of our life to learn how to live, and – something that may surprise you more – it takes just as long to learn how to die.

Distringit librorum multitudo (the abundance of books is distraction).

Life is divided into three parts: what was, what is and what shall be. Of these three periods, the present is short, the future is doubtful and the past alone is certain.

He who is brave is free.

I am not a ‘wise man,’ nor . . . Shall I ever be. And so require not from me that I should be equal to the best, but that I should be better than the wicked. It is enough for me if every day I reduce the number of my vices, and blame my mistakes.