And thus, the actions of life often not allowing any delay, it is a truth very certain that, when it is not in our power to determine the most true o… - René Descartes

When it is not in our power to determine what it true, we ought to follow what is most probable.

I was aware that the reading of all good books is indeed like a conversation with the noblest men of past centuries who were the authors of them, nay a carefully studied conversation, in which they reveal to us none but the best of thoughts.

Dubium sapientiae initium (Doubt is the origin of wisdom).

But immediately upon this I observed that, whilst I thus wished to think that all was false, it was absolutely necessary that I, who thus thought, should be somewhat; and as I observed that this truth, I think, therefore I am (COGITO ERGO SUM), was so certain and of such evidence that no ground of doubt, however extravagant, could be alleged by the sceptics capable of shaking it, I concluded that I might, without scruple, accept it as the first principle of the philosophy of which I was in search