“The so-called physical universe – “the world so described” – turns out to be constituted by mathematical structures which we ourselves have imposed; in a word, it proves to be “man-made.” Yet this way of putting it is also misleading; for inasmuch as physical knowledge is partly objective, “the world so described” must be “partly objective” as well. One is left with a curiously equivocal conception, which may enlighten the wise but is bound to deceive the unwary.”