Rene Descartes Philosophical Quotations

Divide each difficulty into as many parts as is feasible and necessary to resolve it.

The first precept was never to accept a thing as true until I knew it as such without a single doubt.

Omnia apud me mathematica fiunt.

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

The only secure knowledge is that I exist.

De omnibus dubitandum