HEREDITY AND BIOLOGY: by H. T. Edge, B. A. (Cantab.)
THE word "heredity" is one that is much conjured with nowadays, so that it is important to understand its meaning and import. In so far as its meaning covers facts ascertained by reliable observation, and correct inferences therefrom, we must be prepared to accord the word the respect which in that case it deserves; but in so far as it may stand for imperfect observations and the faulty theories inferred therefrom, we must be equally prepared to apply scrutiny and reserve.
One thing we find is that the word is frequently used, even by accredited authorities on biology, in a variable sense; in the course of an argument the word has two or more distinct meanings, and the arguer does not seem to be aware of the variation. This of course indicates a nebulosity in the reasoning and leads to confusion and wrong conclusions. For instance, in a particular case, where a lecturer is reported, we find that he uses the word (1) in the sense of "the fact that organic cells reproduce their kind," and (2) in the sense of "some power or faculty in virtue of which they reproduce their kind." These two senses are quite distinct, and would have been given separate heads in a dictionary; to ignore the distinction in an argument both arises from and creates confusion.
But let us at present consider the second meaning—that of some power or property in virtue of which an organic cell can reproduce its kind. Biology, within its present scope, must confine itself to admitting the existence of this power and to tracing its workings. The source of the power lies outside the field of ordinary biological research. For, granted that physical matter is actuated by an agency, that agency must be immaterial; or at least, if material, then material in another sense than that in which physical matter is material. Now biologists may claim that this phase of the subject does not concern them; and that point we should be willing to concede in all cases where the investigations were confined to their appropriate limits—that is, to the limits appropriate to a confessedly limited science. But what we often actually find is that theorists overstep these limits and assume an attitude of positiveness and authority to which (by the logic of their own admission) they are not entitled. We even find proposals to base legislation upon biological theories; and there is the danger that in small self-governed communities such experiments may actually be carried into effect. When it comes to this therefore we are justified in inquiring more jealously into the credentials of biology; for we do not readily concede the right to be governed by people who have confessed that certain vital phases of their subject do not concern them.
Hence, however the case may stand as regards merely theoretical science, when there is an attempt to apply theories to matters of government and public policy, the restrictions become a matter of vital importance. If we are to achieve successful results in applied biology, then we must positively know something about these mysterious potencies which lie behind matter and which many biologists say do not concern them; for these forces actually exist and count, whether biologists understand them or not; and though they may be ignored on paper, their effects cannot be ignored.
That which lies behind matter is mind—something well known to our experience but not definable in terms of space. The mental aspect of heredity is far more important than the merely physical. The bearing of this truth upon the question of race-improvement and the elimination of degenerate types is important. In paying so much attention to the physical side of the question we are ignoring the important factors and exaggerating those of lesser importance.
In agriculture, attention to the soil is all very well and necessary; but attention to the nature of the seed planted is generally considered as counting for a good deal in determining the nature of the crop to be reaped. Biological theorists are flooding us with schemes for improving the soil in which the human plant grows; and very excellent some of these schemes are. But what about the seeds of the human plant? Nay more; we have not even exhausted the question of the soil; for besides the physical soil, is there not the mental soil? In short, an abundance of factors enter into the question, all of which are of vital import, yet of which but a few fall under the attention of biological theorists.
Heredity includes the two factors of innate potentiality and environment; but the former, since it escapes the observation of physical science, is minimized in favor of the latter. There is an attempt to make environment account for the whole set of phenomena; as though the nature of the crop depended entirely upon the soil and not at all upon the nature of the seed.
In the question of parental transmission the same considerations apply. While it is true that the offspring derives many of its characteristics from its parents, and others from its surroundings, we know that parentage and environment cannot explain everything. There is another factor; and this factor is what corresponds to the seed in our illustration from agriculture. In fact it is the innate character of the individual. For of a man's character, part is due to parentage and environment and part is inherent in the individual himself. The character is the resultant of these two components. The influence of this inherent factor is seen in families, where, though all the children have the same parents, the characters may be widely different. We are aware that an attempt is made to explain this fact by saying that the different children have combined the characteristics of the parents in different proportions; but this is not an explanation of the cause, but merely a restatement of the problem in another form.