Page:The Works of John Locke - 1823 - vol 01.djvu/294

 218 think of infinite space or duration, we at first step usually make some very large idea, as perhaps of millions of ages, or miles, which possibly we double and multiply several times. All that we thus amass together in our thoughts is positive, and the assemblage of a great number of positive ideas of space or duration. But what still remains beyond this, we have no more a positive distinct notion of, than a mariner has of the depth of the sea; where, having let down a large portion of his sounding-line, he reaches no bottom: whereby he knows the depth to be so many fathoms, and more; but how much the more is he hath no distinct notion at all: and could he always supply new line, and find the plummet always sink, without ever stopping, he would be something in the posture of the mind reaching after a complete and positive idea of infinity. In which case let this line be ten, or one thousand fathoms long, it equally discovers what is beyond it; and gives only this confused and comparative idea, that this is not all, but one may yet go farther. So much as the mind comprehends of any space, it has a positive idea of; but in endeavouring to make it infinite, it being always enlarging, always advancing, the idea is still imperfect and incomplete. So much space as the mind takes a view of in its contemplation of greatness, is a clear picture, and positive in the understanding: but infinite is still greater. 1. Then the idea of so much is positive and clear. 2. The idea of greater is also clear, but it is but a comparative idea, viz. the idea of so much greater as cannot be comprehended; and this is plainly negative, not positive. For he has no positive clear idea of the largeness of any extension (which is that sought for in the idea of infinite), that has not a comprehensive idea of the dimensions of it; and such nobody, I think, pretends to in what is infinite. For to say a man has a positive clear idea of any quantity, without knowing how great it is, is as reasonable as to say, he has the positive clear idea of