Authors sometimes plead the difficulty of their subject, as an excuse for the want of Perspicuity. But the excuse can rarely, if ever, be sustained. For whatever a man conceives clearly, that it is in his power, if he will be at the trouble, to put into distinct propositions, to express clearly to others: and upon no subject ought any man to write, where he cannot think clearly. His ideas, indeed, may, very excusably, be on some subjects incomplete or inadequate; but still, as far as they go, they ought to be clear; and, wherever this is the case, Perspicuity in expressing them is always attainable. The obscurity which reigns so much among many metaphysical writers is, for the most part, owing to the indistinctness of their own conceptions. They see the object but in a confused light; and, of course, can never exhibit it in a clear one to others.
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