The problem of religion—that is, of the relations of man with the supernatural, with God and immortality, with the soul, our personality or the ego, and its existence or nonexistence after death—is the greatest and deepest which ever confronted mankind. In the present state of human knowledge, science can give no definite and final conclusions on these subjects, because of the limitations inherent in science.
We must realize that all our knowledge and information and the entire structure of science are ultimately derived from the perceptions of our senses and thereby limited in the same manner and to the same extent as our sense perceptions and our intellect are limited. The success or failure of scientific achievement largely depends on the extent to which we can abstract—that is, make our observations and conclusions independent of the limitations of the human mind. But there are limitations inherent in the human mind beyond which our intellect cannot reach, and therefore science does not and cannot show us the world as it actually is, with its true facts and laws, but only as it appears to us within the inherent limitations of the human mind.
The greatest limitation of the human mind is that all its perceptions are finite, and our intellect cannot grasp the conception of infinity. The same limitation therefore applies to the world as it appears to our reasoning intellect, and in the world of science there is no infinity, and conceptions such as God and the immortality of the ego are beyond the realm of empirical science. Science deals only with finite events in finite time and space, and the farther we pass onward in space or time, the more uncertain becomes the scientific reasoning, until, in trying to approach the infinite, we are lost in the fog of unreasonable contradiction, "beyond science"—that is, "transcendental".
Thus, we may never know and understand the infinite, whether in nature, in the ultimate deductions from the laws of nature in time and in space, or beyond nature, on such transcendental conceptions as God and immortality. But we may approach these subjects as far as the limitations of our mind permit, reach the border line beyond which we cannot go, and so derive some understanding of how far these subjects may appear nonexisting or unreasonable, merely because they are beyond the limitations of our intellect.
There appear to me two promising directions of approach—first, from the complex of thought and research, which in physics has culminated in the theory of relativity; and, second, in a study of the gaps found in the structure of empirical science and what they may teach us.
All events of nature occur in space and in time. Whatever we perceive, whatever record we receive through our senses, always is attached to, and contained in, space and time. But are space and time real existing things? Have they an absolute reality outside of our mind, as a part or framework of nature, as entities—that is, things that are? Or are they merely a conception of the human mind, a form given by the character of our mind to the events of nature—that is, to the hypothetical cause of our sense perceptions? Kant, the greatest and most critical of all philosophers, in his Critique of Pure Reason (Kritik der Reinen Vernunft), concludes that space and time have no absolute existence, but are categories—that is, forms in which the human mind conceives his relation to nature. The same idea is expressed by the poet-philosopher Goethe in his dramatic autobiography Faust (in the second part), when he refers to the "Mütter," to the marriage of Achilles and Helena "outside of all time." It is found in ancient time. So Revelation speaks of "there should be time no longer" (ὅτι χρόνος οὐκέτι ἔσται [Transliterated: hoti chronos ouketi estai]).
The work of the great mathematicians of the nineteenth century—Gauss, Riemann, Lobatschefsky, Bolyai—offered further evidence that space is not an empirical deduction from nature, but a conception of the mind, by showing that various forms of space can be conceived, differing from one another and from the form in which the mind has cast the events of nature (the "Euclidean" space). Finally, physical science, in the theory of relativity, has deduced the same conclusions: space and time do not exist in nature by themselves, as empty space and empty time, but their existence is only due to things and events as they occur in nature. They are relative in the relation between us and the events of nature, so much so that they are not fixed and invariable in their properties, but depend upon the observer and the conditions of observation.
We can get an idea of how utterly our perception of nature depends on the particular form of our time conception by picturing to ourselves how nature would look if our time perception were 100,000 times faster, or 100,000 times slower.
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.