In the first case, with our sense perceptions 100,000 times faster, all events in nature would appear to us 100,000 times slower. This would then be a stationary and immovable world. The only motion which we could see with our eyes would be that of the cannon ball, which would crawl slowly along, at less than a snail's pace. The express train going at sixty miles per hour would appear to stand still, and deliberate experiment be required to discover its motion. By noting its position on the track, and noting it again after a period of time as long as five minutes appears to us now, we should find its position changed by three inches. It would be a dangerous world, as there would be many objects--not distinguishable to the senses from other harmless objects--contact with which would be dangerous, even fatal; and one and the same object (as the express train) might sometimes be harmless (when at rest), sometimes dangerous (when in motion), without our senses being able to see any difference.

On the other hand, with our sense perceptions 100,000 times slower, all events in nature would appear to us to occur 100,000 times faster. There would be little rest in nature, and we should see plants, and even stones, move. We should observe, in a period of time not longer than a minute or two appear to us now, a plant start from seed, grow up, flower, bring fruit, and die. Sun and moon would be luminous bands traversing the sky; day and night alternate seconds of light and darkness. Much of nature, all moving things, would be invisible to us.

If I moved my arm, it would disappear, to reappear again when I held it still. It would be a usual occurrence to have somebody suddenly appear and just as suddenly disappear from our midst, or to see only a part of a body. The vanishing and the appearance of objects would be common occurrences in nature; and we should speak of "vanishing" and "appearing," instead of "moving" and "stopping." Collisions, usually harmless, with invisible objects would be common occurrences.

As seen, nature and its laws would appear to us very different from what we find them now, with our present time perception.

Thus philosophy, mathematics, and physical science agree that s.p.a.ce and time cannot be ent.i.ties, but are conceptions of the human mind in its relation to nature. But what does this mean, and what conclusions follow from it?

The s.p.a.ce of our conception is three-dimensional--that is, extended in three directions. For instance, the north-south direction, the east-west direction, and the up-down direction. Any place or "point" in s.p.a.ce thus is located, relative to some other point, by giving its three distances from the latter, in three (arbitrarily chosen) directions.

Time has only one dimension--that is, extends in one direction only, from the past to the future--and a moment or "point" in time thus is located, with reference to another point in time, by one time distance.

But there is a fundamental difference between our s.p.a.ce conception and our time conception, in that we can pa.s.s through time only in one direction, from the past to the future, while we can pa.s.s through s.p.a.ce in any direction, from north to south, as well as from south to north--that is, time is irreversible, flows uniformly in one direction, while s.p.a.ce is reversible, can be traversed in any direction. This means that when we enter a thing in s.p.a.ce, as a house, we can approach it, pa.s.s through it, leave it, come back to it, and the thing therefore appears permanent to us, and we know, even when we have left the house and do not see it any more, that it still exists, and that we can go back to it again and enter it. Not so with time. On approaching a thing in time, an event such as a human life, it extends from a point in time--birth--over a length of time--the life--to an end point in time--death--just as the house in s.p.a.ce extends from a point in s.p.a.ce--say the north wall--over a length of s.p.a.ce--its extent--to an end point in s.p.a.ce--say the south wall. But when we pa.s.s beyond the end point of an event in time--the death of a life--we cannot go back to the event any more; the event has ceased, ended, the life is extinct.

But let us imagine that the same irreversibility applied to the conception of s.p.a.ce--that is, that we could move through s.p.a.ce only from north to south, and not in the opposite direction. Then a thing in s.p.a.ce, as a house, would not exist for us until we approached it. When we were approaching it, it would first appear indistinctly, and more and more distinctly the nearer we approached it, just as an event in time does not exist until we reach the point of its beginning, but may appear in antic.i.p.ation, in time perspective, when we approach it, the more distinctly, the closer we approach it, until we reach the threshold of the time span covered by the event, and the event begins to exist, the life is born. So to us, if we could move only from north to south, the house would begin to exist only when we reached its north door. That point would be the "birth" of the house. Pa.s.sing through the span of s.p.a.ce covered by the house--this would for us be its existence, its "life," and when we stepped out of the south door the house would cease to exist for us, we could never enter it and turn back to it again--that is, it would be dead and extinct, just as the life when we pa.s.s beyond its end point in time. Thus birth and death, appearance and extinction of an event in time, as our life, are the same as the beginning and end point of a thing in s.p.a.ce, like a house. But the house appears to us to exist permanently, whether we are in it, within the length between beginning and end point, or not; while the event in time, our life, appears to us to exist only during the length of time when we are between its beginning and its end point in time, and before and after it does not exist for us, because we cannot go back to it or ahead into it.

But a.s.sume time were reversible, like s.p.a.ce--that is, we could go through it in any direction. There would then be no such thing as birth or origin, and death or extinction, but our life would exist permanently, as a part or span of time, just as the house exists as a part or section of s.p.a.ce, and the question of immortality, of extinction or nonextinction by death, would then be meaningless. We should not exist outside of the span of time covered by our life, just as we do not exist outside of the part of s.p.a.ce covered by our body in s.p.a.ce, and to reach an event, as our life, we should have to go to the part of s.p.a.ce and to the part of time where it occurs; but there would be no more extinction of the life by going beyond its length in time as there is extinction of a house by going outside of its door, and everything, like a human being, would have four extensions or dimensions--three extensions in s.p.a.ce and one in time.[9]

If s.p.a.ce and time, and therefore the characteristics of s.p.a.ce and time, are not real things or ent.i.ties, but conceptions of the human mind, then those transcendental questions, as that of immortality after death and existence before birth, are not problems of fact in nature or outside of nature, but are meaningless, just as the question whether a house exists for an observer outside of the s.p.a.ce covered by it. In other words, the questions of birth and death, of extinction or immortality, are merely the incidental results of the peculiarity of our conceptions of time, the peculiarity that the time of our conceptions is irreversible, flows continuously at a uniform rate in the same direction from the past to the future.

But if time has no reality, is not an existing ent.i.ty, then these transcendental problems resulting from our time conception, of extinction or immortality, have no real existence, but are really phenomena of the human mind, and cease to exist if we go beyond the limitations of our mind, beyond our peculiar time conception.

It is interesting to realize that the modern development of science, in the relativity theory, has proved not only that time is not real, but a conception, but also has proved that the time of our conception does not flow uniformly at constant rate from past to future, but that the rate of the flow of time varies with the conditions; the rate of time flow of an event slows down with the motion relative to the event.

But the conception of a reversal of the flow of time is no more illogical than the conception of a change of the rate of the flow of time. It is inconceivable, because it is beyond the limitations of our mind.

Thus we see that the questions of life and death, of extinction and immortality, are not absolute problems, but merely the result of the limitations of our mind in its conception of time, and have no existence outside of us.

After all, to some extent we conceive time as reversible, in the conception of historical time. In history we go back in time at our will, and traverse with the mind's eye the times of the past, and we then find that death and extinction do not exist in history, but the events of history, the lives of those who made history, exist just as much outside of the span of time of their physiological life--that is, are immortal in historical time. They may fade and become more indistinct with the distance in time, just as things in s.p.a.ce become more indistinct with the distance in s.p.a.ce, but they can be brought back to full clearness and distinction by again approaching the things and events, the former moving through s.p.a.ce, the latter moving through the historical time--that is, by looking up and studying the history of the time.

THE ENt.i.tY "X"

Scientifically, life is a physico-chemical process. Transformations of matter, with which the chemist deals, and transformations of energy, with which the physicist deals, are all that is comprised in the phenomenon of life; and mind, intellect, soul, personality, the ego, are mere functions of the physico-chemical process of life, vanishing when this process ceases, but are not a part of the transformations of matter and of energy. If you thus speak of "mental energy," it scientifically is a misnomer, and mind is not energy in the physical sense. It is true that mental effort, intellectual work, is accompanied by transformations of matter, chemical changes in the brain, and by transformations of energy. But the mental activity is not a part of the energy or of the matter which is transformed, but the balance of energy and of matter closes.

In the energy transformations accompanying mental activity, just as much energy of one form appears as energy of some other form is consumed, and the mental activity is no part of the energy. In the transformations of matter accompanying mental activity, just as much matter of one form appears as matter of some other form is consumed, and the mental activity is no part of either--that is, neither energy nor matter has been transformed into mental activity, nor has energy or matter been produced by mental activity. All attempts to account for the mental activity as produced by the expenditure of physical energy, or as producing physical energy--that is, exerting forces and action--have failed and must fail, and so must any attempt to record or observe and measure mental activity by physical methods--that is, methods sensitive to the action of physical forces.

But what, then, is mind? Is it a mere phenomenon, accompanying the physico-chemical reactions of life and vanishing with the end of the reaction, just as the phenomenon of a flame may accompany a chemical reaction, and vanish when the reaction is completed? Or is mind an ent.i.ty, just like the ent.i.ty energy and the ent.i.ty matter, but differing from either of them--in short, a third ent.i.ty? We have compared mind with the phenomenon of a flame accompanying a chemical reaction; but, after all, the flame is not a mere phenomenon, but is an ent.i.ty, is energy.

More than once, in the apparently continuous and unbroken structure of science, wide gaps have been discovered into which new sections of knowledge fitted, sections the existence of which had never been suspected. So in Mendelejeff's _Periodic System of the Elements_ all chemical elements fitted in without gaps--in a continuous series (except a few missing links, which were gradually discovered and filled in).

Nevertheless, the whole group of six n.o.ble gases, from helium to emanium, were discovered and fitted into the periodic system at a place where n.o.body had suspected a gap.

One of the most interesting of such unsuspected gaps in the structure of science is the following, because of its pertinency to the subject of our discussion.

In studying the transformations of matter, the chemist records them by equations of the form:

(1) 2H_{2} + O_{2} = 2H_{2}O, which means:

Two gram molecules of hydrogen H_{2}(2 X 2 = 4 grams) and 1 gram molecule of oxygen O_{2}(1 X 32 grams), combine to 2 gram molecules of water vapor H_{2}O (2 X 18 = 36 grams).

For nearly a hundred years chemists wrote and accepted this equation; innumerable times it has been experimentally proved by combining 4 parts of hydrogen and 32 parts of oxygen to 36 parts of water vapor; so that this chemical equation would appear as correct and unquestionable as anything can be.

Nevertheless, it is wrong, or rather incomplete. It does not give the whole event, but omits an essential part of it, and now we write it:

(2) 2H_{2} + O_{2} = 2H_{2}O + 293,000 J., which means:

The matter _and energy_ of 2 gram molecules of hydrogen, and the matter _and energy_ of 1 gram molecule of oxygen, combine to the matter _and energy_ of 2 gram molecules of water vapor and 293,000 joules, or units, of _free energy_.

For a hundred years the chemists thus saw only the material transformation as represented by equation (1), but overlooked and did not recognize the energy transformation coincident with the transformation of matter, though every time the experiment was made, the 293,000 J. of energy in equation (2) made themselves felt as flame, as heat and mechanical force, sometimes even explosively shattering the container in which the experiment was made. But the flame and the explosion appeared only as an incidental phenomenon without significance, as it represents and contains no part of the matter, but equation (1) gives the complete balance of matter in transformation. It was much later that the scientists realized the significance of the flame accompanying the material transformation as not a mere incidental phenomenon, but as the manifestation of the ent.i.ty energy, permanent and indestructible, like matter, and the complete equation (2) appeared, giving the balance of energy as well as the balance of matter--that is, coincident with the transformation of matter is a transformation of energy, and both are indissoluble from each other, either involves the other, and both may be called different aspects of the same phenomenon.

But we have seen, when mental activity occurs in our mind, chemical and physical transformations accompany it, are coincident with it, and apparently indissoluble from it. Does there possibly exist the same relation between mental activity and the transformations of energy and matter, as we have seen to exist between the latter two? Are mental activity, energy transformation, and transformation of matter three aspects of the same biochemical phenomenon?

If for nearly a hundred years equation (1) was considered complete, until we found that one side was incomplete, and arrived at the more complete equation (2), the question may well be raised: Is equation (2) complete, dealing as it does with two ent.i.ties, matter and energy, or is it not possibly still incomplete, and a third ent.i.ty should appear in the equation, an ent.i.ty "X," as I may call it, differing from energy and from matter, just as energy and matter differ from each other, and therefore not recognizable and measurable by the means which measure energy or matter, just as energy cannot be measured by the same means as matter?

That is, the complete equation of transformation would read:

(3) 2H_{2} + O_{2} = 2H_{2}O + 293,000 J. + X, involving all three ent.i.ties, matter, energy, and mind, pertaining, respectively, to the realm of chemistry, of physics, and of psychology, or possibly a broader science of which psychology is one branch.

There is no scientific evidence whatsoever of the existence of such a third ent.i.ty, "X," but all our deductions have been by a.n.a.logy, which proves nothing--that is, by speculation, dreaming, and unavoidably so--since in these conceptions we are close to the border line of the human mind where logical reasoning loses itself in the fog of contradiction. But at the same time there is no evidence against the conception of an ent.i.ty "X"; it is not illogical, at least no more so than all such general conceptions, no more so than, for instance, that of energy or of matter. As empirical science deals with energy and matter, and ent.i.ty "X" is neither, it could not be observed by any of the methods of experimental physics or chemistry.

If mind is a third ent.i.ty, correlated with the ent.i.ties of energy and of matter, we should expect that mental activity, or ent.i.ty "X," should occur not only in the highly complex transformations of energy and of matter taking place in the brains of the highest orders of living beings, but that ent.i.ty "X" should appear in all physico-chemical reactions, just as energy transformations always occur in transformations of matter, and inversely. But this seems not so, and in most of the transformations of energy and of matter ent.i.ty "X" does not appear. However, we have no satisfactory means of recognizing ent.i.ty "X," no methods of studying it. Therefore, it may well be that it is noticed only in those rare instances when it appears of high intensity, but in most reactions ent.i.ty "X" may be so small or appear in such way as to escape observation by the means and by the methods now available.

Like energy or matter, ent.i.ty "X" may have many forms in which it is not recognized by us, just as for a long time the flame was not recognized as the ent.i.ty energy.

To ill.u.s.trate, again by a.n.a.logy: In many transformations of matter, indeed, in most of the more complex ones of the organic world, the concurrent energy transformation is of such slowness and of such low intensity that it appears nonexisting, and can be discovered and measured only by the delicate experiments devised by science.

Furthermore, the energy may appear in different forms. Thus the 293,000 J. of energy in equation (2) may appear as heat, or as electrical energy, or as a combination of heat, light, sound, and mechanical energy. Now a.s.sume that we could observe and notice only one of the forms of energy--for instance, only electrical energy. We should then find that in the equation (1) we only sometimes get energy--that is, electrical energy--under special peculiar conditions, but usually do not seem to get any of the ent.i.ty energy, simply because we do not recognize it in the form in which it appears. a.n.a.logously, there might be a term of ent.i.ty "X" in all transformations, even such simple ones as equation (3), but ent.i.ty "X" may appear in a far different, simpler form. It would mean that "mind" is only one form of ent.i.ty "X," perhaps the high-grade form, as it appears in highly complex reactions. In the simpler physico-chemical processes of nature, ent.i.ty "X" also would appear, but in other, simpler forms. It would mean that things such as mind and intellect are not limited to the higher living beings, but characteristics akin thereto would be found grading down throughout all living and inanimate nature. This does not appear unreasonable when we consider that some characteristics of life are found throughout all nature, even in the crystal which, in its mother liquor, repairs a lesion, "heals a wound," or which, in the colloidal solution, may be "poisoned" by prussic acid.

a.s.sume, then, that mind, intellect, personality, the ego, were forms of a third ent.i.ty, an ent.i.ty "X," correlated in nature with the ent.i.ties energy and matter. Then, just as energy and matter continuously change their forms, so with the transformations of energy and of matter, ent.i.ty "X" would continuously change, disappear in one form and reappear in another form. Ent.i.ty "X" could therefore not exist permanently in one and the same form, and the permanency of the ego--that is, immortality--would still be illogical, would not exist within the realm of science, but would carry us beyond the limitations of the human mind into the unknowable. Permanency of the ego--that is, individual immortality--would require a form of ent.i.ty "X," in which it is not further transformable. This would be the case if the transformations of ent.i.ty "X" are not completely reversible, but tend one definite direction, from lower-grade to higher-grade forms, and the latter thus would gradually build up to increasing permanency. There is nothing unreasonable in this, but a similar condition--in the reverse direction--exists with the transformations of energy. They also are not completely reversible, but tend in a definite direction, from higher- to lower-grade form--unavailable heat energy (the increase of entropy by the second law of thermodynamics). Thus in infinite time the universe should come to a standstill, in spite of the law of conservation of energy, by all energy becoming unavailable for further transformation--that is, becoming dead energy. If ent.i.ty "X" existed, could it not also have become unavailable for further transformation by reaching its maximum high-grade form and thus become not susceptible to further change--that is, "immortal"--just as the unavailable heat of the physicist is "immortal," and not capable of further transformation? Here we are again in the fog of illogic, beyond the limitations. However, it sounds familiar to the Nirvana of the Buddhist.

Physics and chemistry obviously could not deal with ent.i.ty "X," and the most delicate and sensitive physical or chemical instruments could get no indication of it, and all attempts at investigation by physical or chemical means thus must be doomed to failure. But such investigations of ent.i.ty "X" belong to the realm of the science of psychology, or, rather, a broader science, of which psychology is one branch dealing with one form of ent.i.ty "X," mind, just as, for instance, electro-physics is one branch of the broader science of physics, dealing with electrical energy, while physics deals with all forms of energy.

In concluding, I wish to say that nothing in the preceding speculations can possibly encourage spiritism or other pseudo-science. On the contrary, from the preceding it is obvious that the alleged manifestations of spiritism must be fake or self-deception, since they are manifestations of energy. Ent.i.ty "X," if it exists, certainly is not energy, and therefore could not manifest itself as such.

FOOTNOTES:

[Footnote 8: From _Harpers Magazine_ for February, 1922.]

[Footnote 9: It is interesting to note that the relativity theory leads to the conception of a symmetrical four-dimensional world s.p.a.ce (Minkowski), in which in general each of the four dimensions comprises s.p.a.ce and time conceptions, and the segregation into three dimensions of s.p.a.ce and one dimension of time occurs only under special conditions of observation. (AUTHOR.)]

BIOGRAPHICAL AND CRITICAL NOTES

SIR ARTHUR KEITH, M.D., LL.D., F.R.S., born in Aberdeen, 1866, was educated at the University of Aberdeen; at University College, London; and at the University of Leipzig. From 1899 to 1902, he was Secretary of the Anatomical Society of Great Britain, and was President of the Royal Anthropological Inst.i.tute from 1912 to 1914. At present he is Hunterian Professor and Conservator of Museum, Royal College of Surgeons, London, and also holds the Fullerian Professorship of Physiology, Royal Inst.i.tution of Great Britain and Ireland. Beginning with his _Introduction to the Study of Anthropoid Apes_ in 1896, he has produced some ten volumes. Among them are _Human Embryology and Morphology_ (1901); _Ancient Types of Man_ (1911); _The Human Body_ (1912); _Menders of the Maimed_ (1919); and _Nationality and Race_ (1920). He was knighted in 1921.

"The Levers of the Human Body" is helpful in ill.u.s.trating the value of diagrams and of a.n.a.logy in the exposition of a mechanism. It may be used also for teaching the student to adapt his work to the audience, for, although prepared at first for an immature audience, its material has since been so adapted that in addition to the general reader it is of particular interest to the physician and to the engineer.

The series of volumes in which _Modern Methods of Book Composition_ appears, is but one of the distinguished services in improving the practice of typography rendered by THEODORE LOW DE VINNE (1828-1914). At his invitation, the chapter, "Mechanical Composition," was contributed by PHILIP T. DODGE, President of the Mergenthaler Linotype Company.