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The long chains of reasonings …

The long chains of reasonings, simple and easy, by which geometricians are wont to achieve their most complex proofs, had led me to suppose that all things, the knowledge of which man may achieve, are strung together in the same way, and that there is nothing so distant as ultimately to be beyond our mental grasp, or so hidden that we cannot uncover it, provided only we avoid accepting falsehoods as true, and always preserve in our thoughts the discipline essential for the deduction of one truth from another.

René Descartes, Le Discours de la méthode pt 2 (1637)(S.H. transl.)