The mathematical is that evident aspect of things within which we are always
already moving and according to which we experience
them as things at all, and as such things. The
mathematical is this fundamental position we take toward
things by which we take up things as already given to
us, and as they must and should be given. Therefore,
the mathematical is the fundamental **presupposition** of
the knowledge of things.

— 'Modern Science, Metaphysics and Mathematics', collected in Basic Writings (1977).

The necessary precondition for the birth of science as we know it is, it would seem, the diffusion through society of the belief that the universe is both rational and contingent. Such a belief is the **presupposition** of modern science and cannot by any conceivable argument be a product of science. One has to ask: Upon what is this belief founded?

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