CHAPTER VI. Time, Space, and Causality-Three Ideas that make Experience possible. 25. AFTER the doctrine of the three stages of thinking expounded in Chapter IV, the next in importance is the doctrine of a priori ideas or forms of the mind that make experience possible. Kant has proved that they are a priori by showing that they are necessary in order to make experience possible, and hence can not ever have been derived from experience. They belong to the very structure, so to speak, of our ego. Our discussion has made it clear that a conception is not a mental picture, but a sort of rule or definition for the formation of mental pictures. The mental pictures thus formed are only illustrations. The mental picture called up by the word oak is an illustration, but does not exhaust the idea of oak. The idea of oak includes an infinite number of possible examples, illustrations, or specimens, all differing one from another, while the picture that we form in the mind is only a particular individual of one species. Inasmuch as all particular specimens of the oak have grown to be what they are (or what they were) by the action of an oak-producing energy, the idea or conscious conception that we form of oak corresponds not to the individual, but to the energy which produces the individual. Moreover, the energy that brings the individual example of an oak into being— causing it to sprout and become a sapling, grow to maturity and bear its crop of acorns, continually appropriating from its environment air, moisture, salts, and other material that it needs, and converting them into vegetable cells-this energy is a more potent reality than its effect, the individual oak. It is the generic process, in fact, and does not stop with one oak, nor a forest of oaks. Our general idea of oaks corresponds to this generic energy, and hence has a deeper reality corresponding to it than the mere individual oak or oaks that we see by the aid of our senses. Sense-perception does not, in fact, amount to much until it is aided by the formation of concepts or general ideas. § 26. Previous to the formation of general ideas, sense-perception is merely the ceaseless flow of individual impressions without observed connection with one another. In fact, we do not perceive at all, strictly speaking, until we bring general ideas to the aid of our sense-impressions. For we do not perceive things except by combining our different senseimpressions that is to say, uniting them by means of the ideas of Time, Space, and Causality. These three ideas are the chief among the conditions necessary for and are not derived from experience—in other words, they are not externally perceived as objects, or learned by contact with them as individual examples. We know that this is so by considering their nature, and especially by noting that they are necessary as conditions for each and every act of experience. We do not mean, of course, that we must be conscious of these ideas of time, space, and causality before any act of experience; nor would we deny that we became conscious of those ideas by analyzing experience (separating it into matter and form, time, space, and causality being the form, and the particular results the matter). What we deny is that they were furnished by sense-impressions; what we affirm is that they were furnished by the mind in its unconscious act of appropriating the sense-impressions and converting them into perception. mind's self-activity is the source of such ideas. This doctrine is, as above noted, the immortal service of Kant to philosophy, and it inaugurates the era of modern philosophy, furnishing for it an adequate psychological basis. We find these ideas in experi The ence, but as furnished by the self-activity of the mind itself, and not as derived from sense-impressions. We may each and all convince ourselves of the impossibility of deriving these ideas from sense-impressions by giving attention to their peculiar nature. We shall see, in fact, that no act of experience can be completed without these ideas. Immanuel Kant called them "forms of the mind "—they may be said to belong to the constitution of the mind itself, because it uses these ideas in the first act of experience, and in all acts of experience. Why could not these ideas be furnished by experience, like ideas of trees and animals, of earth and sky? The answer is: Because the ideas of time and space involve infinitude, and the idea of causality involves absoluteness; and neither of these ideas could by any possibility be received through the senses. For we can see, hear, and feel only that which is here and now, and not that which is everywhere and always. And it is not correct to say that we derive even ideas of trees and animals, earth and sky, from sense-impressions, because senseimpressions can not become ideas until they are brought under the forms of time, space, and causality. Before this they are merely sensations; after this they are ideas of possible or real objects existing in the world. Let the psychologist who believes that all ideas are derived from sense-impressions explain how we could receive by such means the idea of what is infinite and absolute. Is not any sense-perception limited to what is here and now? How can we perceive by the senses what is omnipresent and eternal? The follower of Hamilton will answer, perhaps: "We can not, it is true, perceive what is infinite and eternal by means of the senses, nor can we conceive or think such ideas by any means whatever. In fact, we do not have such ideas. Time and space and causality do not, as you assert, imply conceptions of infinitude or absoluteness. All supposed conceptions of the infinite and absolute are merely negative ideas, which express our incapacity to conceive the infinite rather than our positive comprehension of it." The issue being fairly presented, we may test the matter for ourselves. § 27. Do we think space to be infinite, or simply as indefinite? Do we not think space as having such a nature that it can only be limited by itself? In other words, would not any limited space or spaces imply space beyond them, and thus be continued rather than limited? Let any one try this thought and see if he does not find it necessary to think space as infinite, for the very reason that all spatial limitation implies space beyond the limit. Space as such therefore can not be limited; the limitation must belong always to that which is within space. An attempt to conceive space itself as limited results in thinking the limited space as within a larger space. Space is of such a nature that it can only be thought as self-continuous, for its very limitations continue it. A limited portion |