Res Gestae

But this gift, I know well, was given to me, that I might not yield to great difficulties, nor ever bow down and humiliate myself; for experience teaches me that all sorrows overcome only weaklings, but yield to the steadfast.

I do not regret what I have done, nor does the recollection of any grave misdeed torment me; either when I was consigned to the shade and obscurity, or after I attained the principate, I have preserved my soul, as taking its origin from relationship with the gods, stainless (in my opinion), conducting civil affairs with moderation, and making and repelling wars only after mature deliberation. And yet success and well-laid plans do not always go hand in hand, since higher powers claim for themselves the outcome of all enterprises.