Meditation 5.18-19

18. Nothing befalls anything which that thing is not naturally made to bear. The same experience befalls another, and he is unruffled and remains unharmed; either because he is unaware that it has happened or because he exhibits greatness of soul. Is it not strange that ignorance and complaisance are stronger than wisdom . . .?

19. Things as such do not touch the soul in the least: they have no avenue to the soul nor can they turn or move it. It alone turns and moves itself, and it makes what is submitted to it resemble the judgements of which it deems itself deserving.