René Descartes

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 greatest minds are capable of the greatest vices as well as
of the greatest virtues.

Dubito ergo cogito; cogito ergo sum. (I doubt, therefore I think;
I think therefore I am.)

It is easy to hate and it is difficult to love. This is how the whole
scheme of things works. All good things are difficult to achieve;
and bad things are very easy to get.


- René Descartes, 1596 - 1650