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.