prove the existence of God or the existence of any particular man. But he can scarcely refuse to examine the conceptions of which men make use when they argue on the subject, for such conceptions evidently call for metaphysical analysis, and there is danger in taking them up uncritically.

The discriminating reader has, I hope, observed that the acceptance of the doctrine contained in the preceding chapters does not imply a rejection of the doctrine of immortality. It has been pointed out that we can best represent to ourselves the relations of minds and bodies under the figure of parallelism. One who accepts this view of the relation may, it is true, feel impelled to infer that the dissolution of the body implies the disappearance of the mind, which has been referred to it, from the realm of existing things. But the inference is, I think, only justified in case one has no positive reason for believing that minds continue to exist. It has been frankly admitted that our knowledge of the relations of mental phenomena and physical phenomena is an extremely vague and indefinite knowledge. We may accept all that psychology and physiology have to tell us, and still confess that we are in complete ignorance of the immediate physical basis of any psychical fact. Neither of the world of matter nor of the world of mind have we such complete information that we are able to say with assurance that what appears to us as the destruction of the body is necessarily the destruction of the physical basis of the mind which has been revealed by it.

Out of our ignorance upon such matters there have sprung up various speculations touching the existence of a "meta-organism," which may continue to exist, and which may still serve as the physical basis of mind. The parallelist has as much right as another to accept such speculations. If he be wise, he will bear in mind, however, that he is here guessing at possibilities, and not reasoning upon a basis of observed fact. These speculations cannot be regarded as falling under the head of science, and the man of science not already impelled to believe in immortality would probably in no instance consider them seriously. Still, we must, I think, admit that such considerations as have been adduced at least serve to indicate that the belief in the immortality of the soul is not necessarily excluded by our knowledge, such as it is, of the facts of the physical world and of the mental world.

In discussing the immortality of the soul, it is well to under

stand clearly what those words may legitimately mean. We recognize that minds exist during a longer or shorter term of years, and that, at the end of that time, the evidence for their existence disappears. The statement that they are immortal is tantamount to the statement that this disappearance of evidence is to be set down to our ignorance. Did we know more, we should still find evidence of their existence.

This means that we are not to conceive of them as existing as disembodied spirits. What can we mean by the existence of a disembodied spirit? We have seen that to affirm real existence of anything is to assign it a place in the system of things. We have also seen, in studying the difficulties into which the subjective idealist falls, that, if we repudiate the physical world, we are left without a system of things. A physical thing that exists nowhere and at no time does not exist. It is equally true that a mind that exists nowhere and at no time1 does not exist. A disembodied spirit is such a mind.

Again. Although we must believe that any mind which continues to exist after the death of the body still holds a relation to the physical world at least analogous to that which it held before, we must not turn the mind into a physical thing, and establish the fact of its immortality by arguments which have a significance only when one is dealing with what is physical. For example, we must set aside all such arguments for immortality as that upon which Bishop Butler lays such emphasis in his famous “ Analogy

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we must not argue from the unity of consciousness to the indiscerptibility" of the soul. He who believes that his mind. will survive the shock of dissolution because it is too small to split, materializes the mind and evidently misconceives the unity of consciousness.

Still again. We must be on our guard against specious arguments drawn from a misconception of the nature of timearguments which would demonstrate the immortality of the soul somewhat as the arguments criticised in the last chapter would demonstrate the existence of God.

Thus, we may not argue that, since time is not something beyond the mind, but is in the mind, it is impossible that the mind should come to an end of existence in time. Such an argument palpably confuses subjective and objective, and ignores that real 1 See Chapter XXIV.

system of things spread out in space and time, in which minds and bodies have their part. He who falls into such an error can make no distinction between what seems and what is; he is robbed of his real world.

Nor may we save ourselves the trouble of proving that the mind will continue to exist after death, by taking refuge in that logical monstrosity, a timeless eternity. He who wishes to persuade us that there may be such a thing as a non-spatial ubiquity must convince us that the word "ubiquity" still means something, after all reference to space and to position in space has been abstracted from; and he who attributes to the mind a timeless eternity should show clearly that the word "eternity" is not a mere sound when all reference to time has been stripped away. It should not be forgotten that a mind, whose mode of existencemay I use the expression?-is timeless, is a mind which never has existed, does not now exist, and never will exist. But I have criticised at length this curious conception of a timeless eternity in a special monograph,1 and I shall not dwell upon it here. It is sufficient to say that no account of it has yet been given which does not surreptitiously introduce the notion of time.

If we refuse to follow such doubtful by-paths to a knowledge of the immortality of the mind, in what direction shall we look for a road that may lead us to our goal? I know of but one. If the world impresses us as a world of purposes and ends, a world in which God is revealed, we may cherish the hope that in the Divine plan there is room for the fulfilment of the aspirations of It is scarcely necessary to say that, in cherishing this hope, we walk by Faith.

man.

1 On Spinozistic Immortality. Philadelphia, 1899.

NOTE ON THE PHYSICAL WORLD-ORDER

BY

EDGAR A. SINGER, JR.

Ir is a matter of common experience that we know something of the meaning of the term body and of the distribution of bodies in space and time before we are acquainted with those physical laws which, where they are known, enable us to describe bodies in new ways and to arrange them in that system which we call the physical world.

The task of discovering these laws, of effecting these descriptions, of constructing this system, belongs to a group of sciences, which, though differing inter se, we are accustomed to include under the single name of physical science. I say we are accustomed to refer to a single physical science: I mean we constantly hear such questions as these: What is the physical basis of life? How far are differences of civilization due to physical, how far to economic, etc., causes? These and similar questions lead us to contrast a science of physical causes with such sciences as biology, psychology, and sociology. But just what sciences are included under the head of the physical, and on what ground they are included is by no means an easy matter to determine. Perhaps all would admit to this class the sciences of physics and chemistry; some, with Helmholtz, would include geometry; others, with the "mechanists," would include biology. But even if we confine ourselves to general physics and chemistry, there are still to be noted wide differences in method. Between mechanics, say, and chemistry, these differences are of sufficient importance to make the problem of finding a common nature in the two branches of science an extremely difficult one.

Nevertheless, I think we can frame a definition which, if applied to the sciences actually known, would bring into one class those which are usually included under the head of physical science, and explain the uncertainty in which we remain concerning others.

I venture to say, then, that a physical science is one which employs in its description of nature only such terms as can adequately be defined by the use of the measuring rod.

What is here meant by the description of nature offered by a science will best be understood if we consider a typical scientific problem:

Given a group of bodies, in which are to be found certain conditions, such as position, volume, mass, temperature, etc., what changes of condition are these bodies going to undergo? To answer this question we should have to be in possession of a law which connects these conditions with one another and with time. The description of nature offered by a science is nothing other than the law or series of laws which it has formulated.

Now, our definition asserts that such a law is a physical law, if to understand its meaning and to verify its truth no knowledge is presupposed other than such as is involved in the use of the measuring rod. In examining the application of this definition to known sciences, its import will be seen more clearly.

The use of the measuring rod, i.e. the description of the procedure by which we may determine the ratio of two lengths, is established in certain of the axioms of geometry. All the axioms are not devoted to this description; some explain the way in which, knowing how to determine the ratio of two lengths, we may determine the relative magnitudes of two angles. We may say, therefore, that all that portion of geometry which is not a definition of measurement, but which records the results of measurement, falls under our definition of a physical science.

Next let us turn to the science of mechanics, and by way of fixing our thoughts we may consider a particular law of mechanics, say, the law of gravitation. This law is of such a nature that in order to apply it to a group of bodies we are obliged to know the mass of each body, its position, and the velocity with which it is moving. Applying the law, we can calculate the values which these conditions will assume at any moment. Now, of the terms used in this description, the positions of the bodies would evidently be determined by the use of the measuring rod in conformity with the principles of geometry; but when we describe the motion of bodies we are obliged to introduce such terms as velocity and acceleration. These terms stand for quantities and are susceptible of measurement, but in determining their values it is not sufficient to measure space magnitudes; we are obliged also to measure periods of time. It may not at once be apparent in what sense time can be determined by the use of the measuring rod, yet the physicist defines time as the hour-angle of a certain star, and this angle is, in the last resort, determined by measurements of length. Time, therefore, and consequently such ratios of space and time as velocity and acceleration, are determined by the use of the measuring rod.

Finally, in our mechanical example we have had to make use of the term mass. This once more appears in our law as a quantity susceptible of measurement; but in what sense can this measurement be