Note 61 — Chapter VI · OF THE PARTICIPLE.

Dr. Beattie observes, “that the fundamental error of those philosophers who deny the existence of present time is, that they suppose the present instant to have, like a geometrical point, neither parts nor magnitude. But as nothing is, in respect of our senses, a geometrical point, (for whatever we see or touch must of necessity have magnitude,) so neither is the present, or any other instant, wholly unextended.” His argument amounts to this, that as a mathematical point is not an object of sense, nor has any real existence, so neither has a metaphysical instant. It is granted. They are each ideal. But does this prove the author’s position, that philosophers have erred in asserting their similarity? or does it evince that no analogy subsists between them? Quite the reverse. The truth is, a geometrical point is purely ideal; it is necessary to the truth of mathematical demonstration, that it be conceived to have no parts. Finding it convenient to represent it to sense, we therefore give it magnitude. A metaphysical instant, or present time, is in like manner ideal; but we find it convenient to assume as present an extended space. The doctor observes, that sense perceives nothing but what is present. It is true; but it should be remembered that not time, but objects which exist in time, are perceived by the senses. It may enable a person to form a correct idea of this matter, if he will ask himself, what he means by present time. If it be the present hour, is it not obvious that part of it is past, and part of it future? If it be the present minute, it is equally clear, that the whole of it cannot be present at once. Nay, if it be the present vibration of the pendulum, is it not obvious that part of it is performed, and part of it remains to be performed? Nor is it possible to stop in this investigation, till present time, strictly speaking, be proved to have no existence. Did it exist, it must be extended; and if extended, it cannot be present, for past and future must necessarily be included in it. If it should be answered, that this proves time, like matter, infinitely divisible, and that the most tedious process will still leave something capable of division, I reply, that as whatever may be left in the one case must be figure, and not a point, so the remainder, in the other, must be a portion of extended time, how minute soever, and not an instant. The process, therefore, must be continued, till we arrive in idea at a point and an instant, incapable of division, being not made up of parts.