Ontology, or the Theory of Being

by P. Coffey

Just as the category Where is indicated by the spatial relations of a body to other bodies, so the category When is indicated, in regard to any event or process, by its commensuration or comparison with other events or processes.

This brings us to the notion of measurement. To measure anything quantitatively is to apply to it successively some quantitative unit taken as a standard and to count the number of times it contains this unit. This is a process of mentally breaking up continuous quantity or magnitude—whether permanent or successive, i.e. whether extension or motion—into discontinuous quantity or multitude. If the measurement of permanent quantity by spatial units, and the choosing of such [pg 326] units, are difficult processes,[379] those of measuring successive quantity and fixing on temporal units are more difficult still. Is there any natural motion or change of a general character, whereby we can measure (externally) the time-duration of all other changes? The motions of the earth itself—on its axis and around the sun—at once suggest themselves. And these motions form in fact the natural general standard for measuring the time of all other events in the universe. All artificial or mechanical devices, such as hour-glasses, watches, clocks, chronometers, etc., are simply contrivances for the more convenient application of that general and natural standard to all particular events.

It requires a little reflection to realize that all our means of measuring time-duration can only attain to approximate accuracy, inasmuch as our faculties of sense perception, no matter by what devices they are aided, are so limited in range and penetration that fluctuations which fall below the minima sensibilia cannot be detected. It is a necessary condition of any motion used as a standard for time-measurement that it be regular. That the standard motions we actually employ are absolutely regular we have no guarantee. We can test their regularity only up to the point at which our power of detecting irregularity fails.

Reflection will also show that our appreciation of time-duration is also relative, not absolute. It is always a comparison of one flow or current of conscious experiences with another. It is the greater regularity of astronomical motions, as compared with changes or processes experienced as taking place within ourselves, that causes us to fix on the former as the more suitable standard for the measurement of time. “There is indeed,” writes Father Maher,[380] “a certain rhythm in many of the processes of our organic life, such as respiration, circulation, and the recurrent needs of food and sleep, which probably contribute much to our power of estimating duration.... The irregular character and varying duration of conscious states, however, soon bring home to us the unfitness of these subjective phenomena to serve as a standard measure of time.” Moreover, our estimate of duration is largely dependent on the nature of the estimated experiences and of our mental attitude towards them: “A period with plenty of varied incident, such as a fortnight's travel, passes rapidly at the time. Whilst we are interested in each successive experience we have little spare attention to notice the duration [pg 327] of the experience. There is almost complete lapse of the ‘enumerating’ activity. But in retrospect such a period expands, because it is estimated by the number and variety of the impressions which it presents to recollection. On the other hand a dull, monotonous, or unattractive occupation, which leaves much of our mental energy free to advert to its duration, is over-estimated whilst taking place. A couple of hours spent impatiently waiting for a train, a few days in idleness on board ship, a week confined to one's room, are often declared to constitute an ‘age’. But when they are past such periods, being empty of incident, shrink up into very small dimensions.... Similarly, recent intervals are exaggerated compared with equal periods more remote. Whilst as we grow older and new experiences become fewer and less impressive, each year at its close seems shorter than its predecessor.”[381]

From those facts it would seem perfectly legitimate to draw this rather surprising inference: that if the rate of all the changes taking place in the universe were to be suddenly and simultaneously altered in the same direction—all increased or all diminished in the same degree—and if our powers of perception were simultaneously so altered as to be readjusted to this new rate of change, we could not become aware of the alteration.[382] Supposing, for instance, that the rate of motion were doubled, the same amount of change would take place in the new day as actually took place in the old. The external or comparative time of all movements—that is to say, the time of which alone we can have any appreciation—would be the same as of old. The new day would, of course, appear only half as long as the old to a mind not readjusted to the new conditions; but this would still be external time. But would the internal, intrinsic time of each movement be unaltered? It would be the same for the readjusted mind as it was previously for the mind adjusted to these previous conditions. By an unaltered mind, however, by the Divine Mind, for instance, the same amount of motion would be seen to constitute the same movement under both conditions, but to take place twice as quickly under the new conditions as it did under the old. This again, however, involves a comparison, and thus informs us merely of external or relative time. If we identify intrinsic time with amount of change, making the latter the measure of the former, we must conclude that alteration in the rate of a motion does not alter its absolute time: and this is evident when we reflect that the very notion of a rate of motion involves the comparison of the latter with some other motion.[383] Finally, we have no positive conception of the manner in [pg 328] which time duration is related to, or known by, the Divine Eternal Mind, which is present to all time—past, present and future.

Besides the question of the relativity of time, there are many other curious and difficult questions which arise from a consideration of time-duration, but a detailed consideration of them belongs to Cosmology. We will merely indicate a few of them. How far is time reversible, at least in the case of purely mechanical movements?[384] Had time a beginning? We know from Revelation that de facto it had. But can we determine by the light of reason alone whether or not it must have had a beginning? The greatest philosophers are divided as to possibility or impossibility of created reality existing from all eternity. St. Thomas has stated, as his considered opinion, that the impossibility of creatio ab aeterno cannot be proved. If a series of creatures could have existed successively from all eternity, and therefore without any first term of the series, this would involve the possibility of an actually infinite multitude of creatures; but an actually infinite multitude of creatures, whether existing simultaneously or successively, is regarded by most philosophers as being self-contradictory and intrinsically impossible. And this although the Divine Essence, being infinitely imitable ad extra, and being clearly comprehended as such by the Divine Mind, contains virtually the Divine exemplars of an infinite multitude of possible creatures. Those who defend the possibility of an actually infinite multitude of creatures consider this fact of the infinite imitability of the Divine Essence as the ground of this possibility. On the other hand, those who hold that an actually infinite multitude is self-contradictory deny the validity of this argument from possibility to actuality; and they bring forward such serious considerations and arguments in favour of their own view that this latter has been at all times much more commonly advocated than the former one.[385] Will time have an end? All the evidence of the physical sciences confirms the truth of the Christian faith that external time, as measured by the motions of the heavens, will have an end. But the internal or intrinsic time which will be the measure of the activities of immortal creatures will have no end.[386]

86. Duration of Immutable Being: Eternity.—We have seen that duration is the perseverance or continuance of a being in its existence. The duration of the Absolutely Immutable Being is a positive perfection identical with the essence itself of this Being. It is a duration without beginning, without end, without change or succession, a permanent as distinct from a successive duration, for it is the duration of the Necessary Being, whose essence is Pure Actuality. This duration is eternity: an interminable duration existing all together. Aeternitas est interminabilis duratio tota simul existens. This is the common definition of eternity in the proper sense of the term—absolute [pg 329] or necessary eternity. The word “interminabilis” connotes a positive perfection: the exclusion of beginning and end. The word “tota” does not imply that the eternity has parts. The expression “tota simul” excludes the imperfection which is characteristic of time duration, viz. the succession of “before” and “after”. The definition given by Boëtius[387] emphasizes these points, as also the indefectible character of immutable life in the Eternal Being: Aeternitas est interminabilis vitae tota simul et prefecta possessio.

There is, in the next place, a kind of duration which has been called hypothetical, relative, or borrowed eternity: aeternitas hypothetica, relativa, participata, also called by scholastics “aeviternitas”. It is the duration in existence of a being that is contingent, but of its nature incorruptible, immortal, such as the human soul or a pure spirit. Even if such a being existed from all eternity its existence would be contingent, dependent on a real principle distinct from itself: its duration, therefore, would not be eternity in the strict sense. On the other hand, once created by God, its nature would demand conservation without end; nor could it naturally cease to exist, though absolutely speaking it could cease to exist were God to withdraw from it His conserving power. Its duration, therefore, differs from the duration of corporeal creatures which are by nature subject to change, decay, and cessation of their being. A contingent spiritual substance has by nature a beginning to its duration, or at least a duration which is not essential to it but dependent on the Necessary Being, a duration, however, which is naturally without end; whereas the duration of the corporeal being has by nature both a beginning and an end.

But philosophers are not agreed as to the nature and ground of the distinction between these two kinds of duration in contingent beings. No contingent being is self-existent, neither has any contingent being the principle of its own duration in its own essence. Just as it cannot begin to exist of itself, so neither can it continue to exist of itself. At the same time, granted that it has obtained from God actual existence, some kind or degree of duration, of continuance in that existence, seems to be naturally due to its essence. Otherwise conservation would be not only really but formally a continued creation. It is such indeed on the part of God: in God there is no variety of activity. But on the part of the creature, the preservation of the latter in existence, and therefore some degree of duration, seems to be due to it on the hypothesis that it has been brought into existence at all. The conserving influence of God is to its duration in existence what the concurring influence of God is to [pg 330] the exercise of its activities.[388] In this sense the duration of a finite being in existence is a positive perfection which we may regard as a property of its nature. But is this perfection or property of the creature which we call duration, (a) essentially successive in all creatures, spiritual as well as corporeal? And (b) is it really identical with their actual existence (or with the reality of whatever change or actualization occurs to their existence), or it is a mode of this existence or change, really distinct from the latter and conferring upon the latter the perfection of continuity or persistence?

This, at all events, is universally admitted: that we cannot become aware of any duration otherwise than through our apprehension of change; that we have direct knowledge only of successive duration; that we can conceive the permanent duration of immutable reality only after the analogy of successive duration, or as the co-existence of immutable reality with the successive duration of mutable things.