Now it is claimed that such a little organism contains the potentiality of all life; that it grows and multiplies, and develops into higher and higher organisms, into all (in short) that we see in the plant and animal world around us. This, it is argued, is all done by natural causes, not by any direction or guidance or intervention of a Divine agency.
Here we must stop to ask how this protoplasm, or simplest form of organic life, came to exist? How did it get its life—its property of taking nourishment, of growing and of giving birth to other creatures like itself?
The denier of creation replies, that just in the same way as, by the laws of affinity, other inanimate substances came together to produce the earth—salts and other compounds we see in the world around us—so did certain elements combine to form protoplasm. This combination when perfected has the property of being alive, just as water has the property of assuming a solid form or has any other of the qualities which we speak of as its properties.
Now it is perfectly true that, treated as a substance, you can take the gummy protoplasm, put it into a glass and subject it to analysis like any other substance. But simple as the substance appears, composition is really very complicated. Professor Allman tells us that so difficult and wonderful is its chemistry, that in fact really very little is known about it. The best evidence we have, I believe, makes it tolerably certain that protoplasm consists of a combination of ammonia, carbonic acid, and water, and that every molecule of it is made up of 76 atoms, of which 36 are carbon, 26 hydrogen, 4 nitrogen, and 10 oxygen.[[12]]
But no chemist has ever been able either to account theoretically for such a composition, still less to produce it artificially. It is urged, however, that it may be only due to our clumsy apparatus and still very imperfect knowledge of chemistry, that we were unable artificially to make up protoplasm.
And of course there is no answer to a supposition of this sort. Nevertheless there is no sort of reason to believe that protoplasm will ever be made; nor, if we could succeed in uniting the elements into a form resembling protoplasmic jelly, is there the least reason to suppose that such a composition would exhibit the irritability, or the powers of nutrition and reproduction, which are essentially the characteristics of living protoplasm. It is not too much to say that, after the close of the controversy about spontaneous generation, it is now a universally admitted principle of science that life can only proceed from life—the old omne vivum ex ovo in a modern form.[[13]]
But here the same sort of argument that was brought forward regarding the possibility of matter and its laws being self-caused, comes in as regards life.
The argument in the most direct form was made use of by Professor Huxley, but it is difficult to believe that so powerful a thinker could seriously hold to a view which will not bear examination, however neatly and brilliantly it may go off when first launched into the air. The argument is that life can only be regarded as a further property of certain forms of matter. Oxygen and hydrogen, when they combine, result in a new substance, quite unlike either of them in character, and possessing new and different properties. The way in which the combination is effected is a mystery, yet we do not account for the new and peculiar properties of water (so different from those of the original gases) as arising from a principle of "aquosity," which we have to invoke from another world. The answer is that the argument is from analogy, and that there is not really the remotest analogy between the two cases. It is true that, as far as we know, electricity is necessary to force a combination of the requisite equivalents of oxygen and hydrogen into water. But though we do not know why this is, or what electricity is, we can repeat the process as often as we will. But mark the difference; the water once existing is obviously only a new form of matter, in the same category with the gases it came from: it neither increases in bulk, nor takes in fresh elements to grow, and give birth to new drops of water. But protoplasm has something quite different—for there may be dead protoplasm and living protoplasm, both identical to the eye and to every chemical test. In either condition, protoplasm, as such, has properties of the same nature (though not of the same kind) as those of water, oxygen gas, or any other matter; it is colorless, heavy, sticky, elastic, and so forth; but besides all that (without the aid of electricity or any physical force we can apply) one has the power of producing more protoplasm—gathering for itself, by virtue of its inherent power, the materials for growth and reproduction.
If directly water was called into existence it could take in nourishment, and divide and go on producing more water—and if some water could do this, while other water (which no available test could distinguish from it in any other respect) could not, then we should be perfectly justified in giving a special name to this power, and calling it "aquosity" or "vitality" or anything else, it being out of all analogy to anything else which we call a "property" of matter.
In the introduction of LIFE into the aeon of organic developmental history, we have a clear and distinct period, as we had when matter came into view, or when the change was ushered in which set the cosmic gas cooling and liquefying, and turning to solid in various form.