| THE MAKING OF THE SCIENTIFIC INVESTIGATOR |
By THOMAS H. MONTGOMERY, Jr.
PROFESSOR OF ZOOLOGY, UNIVERSITY OF PENNSYLVANIA
THE question is old but important, how far a man may influence his destiny and career by power of will and by training. Very often it is argued that his future lies entirely with himself, that he is modeling clay in his own hands. From this comes the expression of "the self-made man." Yet "there's a divinity that shapes our ends, rough hew them how we will," a might that the biologist calls inheritance. For by no manner of endeavor can a man make himself a bird or fish, nor can he divorce his mind from his body. An organism may be introduced to new conditions of life, by volition or by circumstance, and though it may change to some extent, it can not become entirely different from what it was at the start and still continue to live. As the twig is bent the tree inclines, that is, bends off from the normal path, but it does not become another kind of tree. The gardener can change the growth of a flower by placing certain solutions in the soil, but he simply adds another substance to it; or the experimenter can prevent a skeleton from developing by withdrawing from the medium certain salts, but he has only subtracted a certain substance. Some qualities may receive an added impulse, others may be retarded, monsters may be engendered, but no man has yet changed one being into a very different one.
Thus there are genetically diverse kinds of beings, and this is as true for men as for the rest of creation. What will be the outcome of any individual is to greatest extent a matter of his inheritance, it is blood that tells. All of us make our advent naked and helpless, all seemingly equally dependent upon the maternal care, all have to learn by experience. Yet no two human infants are alike, except to the inexperienced eyes of an old bachelor, for because they are of different parentage they possess at the beginning different qualities, and it is probable that infants arc as unlike as full-grown men and women, though in not the same ways. Indeed, every step in our growth has been conditioned by our ancestry. For the organism is much more than a set of substances and structures, it is a chain of processes linked continuously with the remote past and the outcome depends very largely upon the initial condition. This is the cardinal point that educators have grasped only recently, and about which some of them are still strangely in doubt. A man can not mold himself entirely, nor can his teachers wholly change him, for he is largely fashioned by his inheritance.
But though inheritance handles the reins, the course of life depends
