Page:Ferrier's Works Volume 1 - Institutes of Metaphysic (1875 ed.).djvu/48

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INSTITUTES OF METAPHYSIC.

manifested in certain quarters of late years, but certainly far from being triumphant, to limit the strictly necessary truths of reason to the smallest possible amount—to confine them to the pure mathematics, if not to explode them even here. This is an interesting question; but, like all others, it can be effectually settled, not by general observations, but only by the production of the subjects in dispute—that is, the necessary truths themselves. These will appear in their proper places. Meanwhile all enlarged argument in their defence, and all detailed explanation of their character, must be avoided, as our purpose at present merely is, to point out the retarding causes of speculation, of which the discountenance thrown on the necessary truths of reason has been undoubtedly one, and one of the most influential.

What necessary truth is.§ 27. A few observations, however, may here be offered, in elucidation of what is meant by necessary truth. A necessary truth or law of reason is a truth or law the opposite of which is inconceivable, contradictory, nonsensical, impossible; more shortly, it is a truth, in the fixing of which nature had only one alternative, be it positive or negative. Nature might have fixed that the sun should go round the earth, instead of the earth round the sun; at least we see nothing in that supposition which is contradictory and absurd. Either alternative was