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 opinions we ought to follow the most probable.
To know what people really think, pay attention to what they do, rather than what they say.
Masked, I advance.
It is only prudent never to place complete confidence in that by which we have even once been deceived.
It is not enough to have a good mind; the main thing is to use it well.
Whenever anyone has offended me, I try to raise my soul so high that the offense cannot reach it.
The greatest minds are capable of the greatest vices as well as of the greatest virtues.
Divide each difficulty into as many parts as is feasible and necessary to resolve it.
I think, therefore I am.
If you would be a real seeker after truth, it is necessary that at least once in your life you doubt, as far as possible, all things.
The reading of all good books is like a conversation with the finest minds of past centuries.
We do not describe the world we see, we see the world we can describe.
De omnibus dubitandum.
I know that I exist; the question is, What is this ‘I’ that ‘I’ know.
The chief cause of human errors is to be found in the prejudices picked up in childhood.
Mathematics is a more powerful instrument of knowledge than any other that has been bequeathed to us by human agency.
He who hid well, lived well.