“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.”

—  René Descartes, book Principles of Philosophy

Original Latin: Veritatem inquirenti, semel in vita de omnibus, quantum fieri potest, esse dubitandum
Variant translation: If you would be a real seeker after truth, you must at least once in your life doubt, as far as possible, all things.
Principles of Philosophy (1644)
Variant: In order to seek truth, it is necessary once in the course of our life, to doubt, as far as possible, of all things.

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René Descartes47
French philosopher, mathematician, and scientist 1596–1650

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