Excerpt:

Why is the universe what it is? That is the riddle of the universe. Can we ever solve it? Can we grasp it at all? Of course we cannot with human minds reach out to the ever-receding infinities of universe beyond universe of stars. Neither can we reach inward to the equal infinities of world within world in the atom. This does not need words. We know that we can never do it. We cannot grasp what it really means that a certain island universe is millions of light-years away. We cannot grasp what it means that the electron moves in its orbit around the proton in the atom a quadrillion times a second. It is no shame to us that we cannot grasp such things as these. Our minds are not geared to the infinite. If they were, could we harness them any more to the ledger, the plough, the tool-chest or the cook-stove? What would it profit to grasp the nebula and the electron, and starve or freeze? But our minds do seem fitted to understand. They can apparently understand the quality and meaning of things whose immensity they cannot grasp. They are evidently fitted to understand everything which can be understood. That seems somehow to be what they are for.

Then can we understand the universe? Can we find why it is what it is? That surely comes first in understanding it. Can we find an organic reason in it, and see it as a whole? Some put it in this way:—"Is there a formula of the universe? And can the formula be known?" It is worth every effort to understand this force or that fact in the world around us. What then is it worth to understand the universe!

Why is the physical world just what it is, and not something quite different? Could the physical world have existed in some other form and order? If it could have been wholly different, why is it what it is? Or if it had to be what it is, why did it have to be so? Is there a reason? What is the reason? It is not enough to say that all things evolved into this present form of things out of a simpler condition. For if they did evolve, why did they evolve into this order of things, and not into something quite different? That is our question. Or if they came at a creative stroke into what they now are, why was it into just this form and character and not into some other?

Is this really a universe, then? That is, has it unity? Has it a structure, with a reason for the structure? For we surely do want, if we can, to see the universe as a whole. If we cannot see it all, which is a more than doubtful possibility, we can at least see what it all means. Can we see it as a universe, a genuine unity, including the world of matter and the world of mind? Is it such a universe, with an organic pattern and principle in it all? In other words, is there a structure of the universe, with a reason for it? What is that structure?

If we had not asked these things before, modern science would drive us to ask them now. This physical universe, this vast fabric of forces, this interplay of laws and energies, why is it so precisely and accurately what it is? There must be a structure of the modern universe. And if there is such a structure, there must be a reason for it, a universal reason why it is just what it is. What is that reason?

To find the structure of the physical universe, we do not need more complicated knowledge. We need to simplify. We need to use what we have. We must find the basic things, which form the universal structure.

What are the basic things? Those things which lie back of all other things? Those things which are the basis of all other things, and include all other things, and exist in all other things? Those will be the basic things. They should not be very hard to find. When we have found them we shall be on our way toward understanding the riddle of the universe. We must find the basic things.

Space

The first one may be agreed upon without difficulty. It is Space—the basic thing in the physical universe. It is back of every other basis of the physical universe. We may have many different views about space, and many speculations. We may think of space as an outward reality, or as our way of seeing the universe. But, in any case, space comes first. Upon one thing we can all agree. Whatever each of us may mean by space, this is, as we all know, a space universe.

What is space? Of what does it consist?

We may speculate much about this. But again we can without difficulty agree on the essential thing. Space as we all know it and live in it and use it consists of three things. We call these three things three dimensions, or three directions. We name them generally length, breadth and height.

Two words may be objected to nowadays, when we talk about "three dimensions." One word is "dimensions," and the other is "three." But for our simpler and basic purpose neither objection will be made.

It may be suggested, and rightly, that the term "dimensions," the term most commonly used, and which therefore we are using, means measurements, and therefore implies limited distances. "Length, breadth and height," too, may be taken as limited terms. "Length" may mean the distance between two definite points, which means a limited distance. "Breadth" also may be used as a term of measurement, rather than a term of unlimited direction. "Height" also may signify a limited distance upward. These terms are not wholly unambiguous when we would signify unlimited space.