Now if space is identical with extension, it must be cognized by the senses and the sensuous imagination. This is unhesitatingly affirmed by Hamilton: "We see extension," and "by the name extension we designate our empirical knowledge of space."[82] So also McCosh: "Of space in the concrete we have an immediate knowledge by the senses, certainly by some of them, such as the touch and sight."[83] Space in this connection can not therefore be regarded as an à priori cognition. It is equally obvious that if space is identical with extension, it must have color and form. This also is admitted by Hamilton: "I can easily annihilate all corporeal existence [in imagination]. I can imagine empty space. But there are two attributes of which I can not divest it—that is, shape and color."[84] Now if space has "shape," that is, figure, it must have dimensions, and accordingly we find almost all philosophers speaking of the three dimensions of space—length, breadth, and depth. That which has length, breadth, and depth must be divisible, must have parts and proportions, must have susceptibilities of exact measurement, and therefore must be finite. This again is the doctrine of Hamilton: "Space is finite, and a finite, that is, a bounded space constitutes a figure"—a sphere.[85] The fundamental doctrine of Hamilton is that "space, like time, is only the intuition or the concept of a certain correlation of existence—of existence, therefore, pro tanto, as conditioned. It is thus itself only a form of the conditioned."[86] But if space be only a correlation of conditioned, and therefore finite existence, how can he speak of it "being conceived as infinite,"[87] and, above all, how can he speak of "the absolute totality" and "the infinite immensity of space."
McCosh, also, though evidently with some hesitation, teaches that "we can conceive proportion in space, and if we take any of these proportional sections, and divide it into two, thought will compel us to say that the two make up the whole. In this sense the parts make up the whole—that is, the subsections make up the section. If the question be extended beyond this, and it be asked, Is infinite space made up of parts? I answer, that as we can have no adequate notion of infinite space, so we can not be expected to answer all the questions which may be put regarding it. It is certain that neither infinite space nor finite space is made up of separate parts. We can speak intelligibly of proportions in finite space, and determine their relations to each other and the whole. I tremble to speak of the proportions of infinite space, lest I be using language which has or can have no proper meaning, and the signification attached to which by me or others might be altogether inapplicable to such a subject. Still there are propositions which we might intelligibly use. It is self-evident that any proportion of space must be less than infinite space. And if infinite space can be conceived as having proportions, and we could conceive all these proportions, then these proportions would be equal to the whole!"[88] Well may the author say that he is "in a region dark and pathless;" for the language here employed "can have no proper meaning" in regard to infinite space. Well may he "tremble to speak of the proportions of infinite space," for what can proportion (pro, for portio, a part) mean except a numerical relation of parts? Proportions—numerical relations—are measurable quantities, therefore finite quantities, and no addition of finite quantities, can make the infinite. What confusion and contradiction is here wrought by this word-jugglery with "the whole and parts" of space!
Cousin, also, falls into the same inaccuracy and confusion. He tells us that "human reason can conceive of a space determined and limited,"[89] therefore divisible, measurable, and finite; and yet at the same time he teaches that "space is illimitable, absolutely continuous, an indivisible unity."[90]
And now let us note the contradictions which flow from this confounding of space with extension, and both with immensity. Space is cognized à posteriori, space is cognized à priori. Space has parts and proportions, space has no parts or proportions. Space is divisible, space is indivisible—an absolute unity. Space is finite, space is infinite. Space is susceptible of exact measurement, space is immeasurable—that is, absolute immensity.
Space and extension are not identical. Extension is simply an attribute of body—the continuity of matter. Space is place, distance, direction, relations of bodies. Space is a certain correlation of finite existences. Immensity is the attribute of the unconditioned Being, the absolute Spirit—that is, God. He is incorporeal, boundless, spaceless, infinite.
2. The same confusion pervades the writings of philosophers in regard to TIME, DURATION, and ETERNITY.
Succession is confounded with duration,[91] duration with time,[92] and time with eternity.[93]
If succession and duration are identical, then, there is no permanent substance underlying the fugitive phenomena of the outer world, and no personal existence which remains the same through all the changes of our mental states. The human mind is simply "a series of feelings," a succession of mental states without any enduring ground principle constituting our personal identity, and we are thus landed in the constructive Idealism of John Stuart Mill.[94] On the other hand, if there be a permanent substance or essence underlying all mental phenomena, whose continuance in existence is measured by phenomenal change, time succession, then duration can not be identical with time, any more than permanence can be the same as change. With finite duration there is necessarily given change; the past is like the future—always a minus in relation to the present.
Furthermore, if time is synonymous with eternity, then eternity is divisible, measurable, it has limits and parts. Time, say the philosophers, has one dimension, while space has three. "We," says McCosh, "represent time as a line,"[95] it must therefore be divisible, and, if divisible, it is legitimate to speak, with Hamilton, of "time and its parts." "Time has succession, or priority and posteriority."[96] And yet this same writer in the same work tells us, "Time has no limits," and "Time can not be divided into separable parts."[97] If time and eternity are identical, eternity has a past, a present, and a future—"eternity ab ante and eternity a post."[98] The eternity past is bounded by the present, it ends now; the eternity to come begins now. We may with propriety ask, How can that which has succession, which is capable of exact measurement, which has a beginning and an end, be infinite? That which had a beginning can not be unbeginning, that which will come to an end can not be endless. Is not the "eternity of time" a contradiction in terms? Is not "absolute time" an absurdity?
Mark, then, the contradictions which flow from the confounding of succession and duration, time and eternity. Time has limits, time has no limits. Time is divisible, time is indivisible. Time is finite, time is infinite. Time is relative, time is absolute. Time is moving, "it flows;" time is immovable, "it does not flow."[99]