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449 as truth, and that 'tis not the justness of our conclusions, which alone gives the pleasure. For these conclusions are equally just, when we discover the equality of two bodies by a pair of compasses, as when we learn it by a mathematical demonstration; and tho' in the one case the proofs be demonstrative, and in the other only sensible, yet generally speaking, the mind acquiesces with equal assurance in the one as in the other. And in an arithmetical operation, where both the truth and the assurance are of the same nature, as in the most profound algebraical problem, the pleasure is very inconsiderable, if rather it does not degenerate into pain: Which is an evident proof, that the satisfaction, which we sometimes receive from the discovery of truth, proceeds not from it, merely as such, but only as endow'd with certain qualities.

The first and most considerable circumstance requisite to render truth agreeable, is the genius and capacity, which is employ'd in its invention and discovery. What is easy and obvious is never valu'd; and even what is in itself difficult, if we come to the knowledge of it without difficulty, and without any stretch of thought or judgment, is but little regarded. We love to trace the demonstrations of mathematicians; but shou'd receive small entertainment from a person, who shou'd barely inform us of the proportions of lines and angles, tho' we repos'd the utmost confidence both in his judgment and veracity. In this case 'tis sufficient to have ears to learn the truth. We never are oblig'd to fix our attention or exert our genius; which of all other exercises of the mind is the most pleasant and agreeable.

But tho' the exercise of genius be the principal source of that satisfaction we receive from the sciences, yet I doubt, if it be alone sufficient to give us any considerable enjoyment. The truth we discover must also be of some importance. 'Tis easy to multiply algebraical problems to infinity, nor is there any end in the discovery of the proportions of conic sections; tho' few mathematicians take any pleasure in these