“Why should it ever have started at all?” said Matthews. “As Matter passes from one form to another, so forces change from one to another. Why should we suppose a beginning—or an end if it comes to that? Why not a perpetually shifting kaleidoscope, going through all its transformations and starting again?”
“Why, my lad,” replied Hoskyns, “because in that case you will come slap up against the second law of thermodynamics, and that will be the end of you.”
“Oh!” said Mr. Perry, “the formula that starts so charmingly about ‘Nothing in the statistics of an assemblage’—that appears to be all the Law and the Prophets nowadays.”
“Yes,” said Hoskyns. “Its general meaning is that Time only works in one direction, and that when all the permutations and combinations have been run through, Time will stop, because there will be nothing further by which we can distinguish its direction. All the possibilities will have been worked out, all the electrons will have been annihilated, and there will be nothing more for them to do and no radiant energy left for them to do it with. That is why there must be an end. And if an end, presumably a beginning.”
“And the end is implicit in the beginning?” said I.
“Yes; but the intermediate stages are not inevitable in detail, only overwhelmingly probable in the gross. There, Perry, if you like, you can reconcile Foreknowledge with Freewill.”
“Life, then, I suppose, is but one more element of randomness,” said I, “in the randomness of things.”
“Presumably,” said Hoskyns.
There was a pause.
“What is Life?” I asked, suddenly.
“Well, Pontius,” said Waters, “if we could answer that question we should probably not need to ask the others. At present—chemically speaking—the nearest definition I can produce is that it is a kind of bias—a lopsidedness, so to speak. Possibly that accounts for its oddness.”
“I’ve said that kind of thing myself,” I said, rather astonished, “just as a sort of feeble witticism. Have I hit on something true by accident?”
“More or less. That is to say, it is true that, up to the present, it is only living substance that has found the trick of transforming a symmetric, optically inactive compound into a single, asymmetric, optically active compound. At the moment that Life appeared on this planet, something happened to the molecular structure of things. They got a twist, which nobody has ever succeeded in reproducing mechanically—at least, not without an exercise of deliberate selective intelligence, which is also, as I suppose you’ll allow, a manifestation of Life.”
“Thank you,” said Perry. “Do you mind saying the first part over again, in words that a child could understand?”
“Well, it’s like this,” said Waters. “When the planet cooled, the molecules of that original inorganic planetary matter were symmetric—if crystallised, the crystals were symmetric also. That is, they were alike on both sides, like a geometrical cube, and their reversed or mirror-images would be identical with themselves. Substances of this kind are said to be optically inactive; that is to say, if viewed through the polariscope, they have no power to rotate the beam of polarised light.”
“We will take your word for it,” said Perry.
“Oh, well, that’s quite simple. Ordinarily speaking, the vibrations in the aether—need I explain aether?”
“I wish you could,” said Hoskyns.
“We will pass aether,” said Perry.
“Thank you. Well, ordinarily the aetheric vibrations which propagate the light takes place in all directions at right angles to the path of the ray. If you pass the ray through a crystal of Iceland spar, these vibrations are all brought into one plane, like a flat ribbon. That is what is called a beam of polarised light. Very well, then. If you pass this polarised light through a substance whose molecular structure is symmetric, nothing happens to it; the substance is optically inactive. But if you pass it through, say, a solution of cane sugar, the beam of polarised light will be twisted, and you will get a spiral effect, like twisting a strip of paper either to the right or to the left. The cane sugar is optically active. And why? Because its molecular structure is asymmetric. The crystals of sugar are not fully developed. There is an irregularity on one side, and the crystal and its mirror image are reversed, like my right hand and my left.” He laid the palm of the right hand on the back of the left to show his meaning. We all frowned and practised on our own hands.
“Very good,” continued Waters. “Now, we can produce in the laboratory, by synthesis from inorganic substances, other substances which were at one time thought to be only the products of living tissues—camphor, for instance, and some of the alkaloids used in medicine. But what is the difference between our process and that of Nature? What happens is this. The substance produced by synthesis always appears in what is called a racemic form. It consists of two sets of substances—one set having its asymmetry right-handed and the other left-handed, so that the product as a whole behaves like an inorganic, symmetric compound; that is, its two asymmetrics cancel one another out, and the product is optically inactive and has no power to rotate the beam of polarised light. To get a substance exactly equivalent to the natural product, we have
