Doubt is the origin of wisdom.
He is the wisest philosopher who holds his theory with some doubt.
The fact is: I no longer believe in my own infallibility. That is why I am lost.
The man who fails to carry out his plans because of his doubts about them, has already failed.
The only limit to our realization of tomorrow will be our doubts of today. Let us move forward with strong and active faith.
Doubt is not a pleasant condition, but certainty is absurd.
