"our perceptions can truly correspond with outer reality, is that of the time-succession of phenomena.Simultaneity, succession, and the regular return of simultaneity or succession, can obtain as well in sensations as in outer events.Events, like our perceptions of them, take place in time, so that the time-relations of the latter can furnish a true copy of those of the former.The sensation of the thunder follows the sensation of the lightning just as the sonorous convulsing of the air by the electric discharge reaches the observer's place later than that of the luminiferous ether."
One experiences an almost instinctive impulse, in pursuing such reflections as these, to follow them to a sort of crude speculative conclusion, and to think that he has at last got the mystery of cognition where, to use a vulgar phrase, 'the wool is short.' What more natural, we say, than that the sequences and durations of things should become known? The succession of the outer forces stamps itself as a like succession upon the brain.
The brain's successive changes are copied exactly by correspondingly successive pulses of the mental stream.The mental stream, feeling itself, must feel the time-relations of its own states.But as these are copies of the outward time-relations, so must it know them too.That is to say, these latter time-relations arouse their own cognition; or, in other words, the mere existence of time in those changes out of the mind which affect the mind is a sufficient cause why time is perceived by the mind.
This philosophy is unfortunately too crude.Even though we were to conceive the outer successions as forces stamping their image on the brain, and the brain's successions as forces stamping their image on the mind, still, between the mind's own changes being successive, and knowing their own succession , lies as broad a chasm as between the object and subject of any case of cognition in the world.A succession of feelings, in and of itself, is not a feeling of succession.And since, to our successive feelings, a feeling of their own succession is added, that must be treated as an additional fact requiring its own special elucidation , which this talk about outer time-relations stamping copies of themselves within, leaves all untouched.
I have shown, at the outset of the article, that what is past, to be known as past, must be known with what is present, and during the 'present' spot of time.As the clear understanding of this point has some importance, let me, at the risk of repetition, recur to it again.
Volkmann has expressed the matter admirably, as follows:
"One might be tempted to answer the question of the origin of the time-idea by simply pointing to the train of ideas, whose various members, starting from the first, successively attain to full clearness.But against this it must be objected that the successive ideas are not yet the idea of succession, because succession in thought is not the thought of succession.
If idea A follows idea B, consciousness simply exchanges one for another.
That B comes after A is for our consciousness a non-existent fact;
for this after is given neither in B nor in A; and no third idea has been supposed.The thinking of the sequence of B upon A is another kind of thinking from that which brought forth A and then brought forth B; and this first kind of thinking is absent so long as merely the thinking of A and the thinking of B are there.In short, when we look at the matter sharply, we come to this antithesis, that if A and B are to be represented as occurring in succession they must be simultaneously represented;
if we are to think of them as one after the other, we must think them both at once."
If we represent the actual time-stream of our thinking by an horizontal line, the thought of the stream or of any segment of its length, past, present, or to come, might be figured in a perpendicular raised upon the horizontal at a certain point.The length of this perpendicular stands for a certain object or content, which in this case is the time thought of, and all of which is thought of together at the actual moment of the stream upon which the perpendicular is raised.Mr.James Ward puts the matter very well in his masterly article 'Psychology' in the ninth edition of the Encyclopædia Britannica, page 64.He says:
"We may, if we represent succession as a line, represent simultaneity as a second line at right angles to the first; empty time -- or time-length without time-breadth, we may say --is a mere abstraction.Now, it is with the former line that we have to do in treating of time as it is, and with the latter in treating of our intuition of time, where, just as in a perspective representation of distance, we are confined to lines in a plane at right angles to the actual line of depth.In a succession of events, say of sense-impressions, A B C D E..., the presence of B means the absence of A and C, but the presentation of this succession involves the simultaneous presence in some mode or other of two or more of the presentations A B C D.In reality, past, present, and future are differences in time, but in presentation all that corresponds to these differences is in consciousness simultaneously."
There is thus a sort of perspective projection of past objects upon present consciousness, similar to that of wide landscapes upon a camera-screen.
