“the present instant,” so-called, has at once temporal succession, the earlier and the later, included within it, and it has a decidedly, and, in fact, a very inconveniently and arbitrarily, limited length. What happens so rapidly or so slowly that we fail to accommodate to the events our ability to take note of the succession as a present and given fact, all such too rapid or too slow series of occurrences, we fail directly to note as matters of clear consciousness. Hence, we constantly lose sight even of our own trains of thought and action, even in instances where we most want to survey them. Our brief, but still by no means indefinitely small time-span of consciousness, determines in this way our whole human form of experience, and of course limits the ethical meaning of our conduct. Yet how long a temporal period, how much duration, shall constitute the finite interval viewed by a given form of consciousness as a now, is a wholly arbitrary matter, so long as now means not the ideal mathematical now, — the negation of all duration, the mere point between present and future, but rather a period, a succession of events, a finite duration. In our consciousness, however, the now of experience does mean just such an actual, brief, but still finite, interval or period of time, within which and during which events succeed one after another. Now nobody can for an instant defend the rationality of supposing that every possible form of consciousness must have the precise human limitation of time-span. Yet a notable alteration of time-span, quite apart from any alteration of the contents that succeed one after another in the minds in question, would constitute a variation of a given type of consciousness whose vast possible meaning,
