There is only one religion, though there are a hundred versions of it.
A life spent making mistakes is not only more honourable, but more useful than a life spent doing nothing.
Progress is impossible without change, and those who cannot change their minds cannot change anything.
No man who is occupied in doing a very difficult thing, and doing it very well, ever loses his self-respect.
The moment we want to believe something, we suddenly see all the arguments for it, and become blind to the arguments against it.