Nature has been doing for centuries, unheeded, what the photographer of to-day thinks is a modern discovery, that is, making composite photographs of us all.
Through this law of inheritance have arisen the intellectual, the moral or the criminal types of humanity, and the process is continuing; the types are becoming more and more marked, or modifying influences are being brought in to change the type.
These influences are also the result of law, even though we may not be able to trace them to their cause. Knowing this, however, we begin to see that heredity is not fatality; that the power to modify the endowments of future generations is ours. To know how to employ it, we should study the law as far as we have opportunity.
This subject is a large one, and no doubt you will some day want to give it a thorough investigation. Just now, however, you will have to accept my statements. I will not make them technical, but strictly practical to you as a young woman desiring that knowledge which shall best fit you for the responsibilities of future life.
A superficial study is rather discouraging. We see with what certainty evil characteristics are transmitted, and we feel that the law is a cruel one; but if we have patience we shall find that, like all laws of God, its purpose is for the benefit of the race. Before we begin to take comfort from the law let us first learn its warnings, one of which is that all weakening of the individual, either in bodily strength, in intellectual power or moral fiber, tends to produce a like weakness in posterity. This is why I say to you that the young people of the present have in their hands the welfare of the future. Their habits to-day are moulding the possibilities of the race. Young women may feel that their individual violation of the laws of health is of no importance, but when they realize that the girls of to-day are the mothers of the future, and that the physical strength or weakness of each individual girl affects the average health of the nation, not only now, but it may be through her posterity for centuries, we can see that each girl's health is a matter of national and of racial importance.
But it is not alone in the physical organization that we can trace the law of heredity in the transmission of undesirable qualities. We find that evil traits and tendencies of mind or morals are transmissible. Galton finds that a bad temper is quite sure to be passed on from one generation to the next, and any peculiarity of disposition in either parents is quite likely to become an inheritance of the child. This fact makes our little faults seem of vastly more importance than otherwise. We can endure them in ourselves, but they strike us very unpleasantly when we are obliged to see them manifested in our children. As the poet says:
"Little faults unheeded, which I now despise;
For my baby took them with her hair and eyes."
It may not strike us very unpleasantly when we speak disrespectfully to our parents, but when our own children show us lack of courtesy and cheerful obedience it cuts deeply, and all the more deeply if we see in their conduct but a repetition of our own.
Of course, if these minor faults are transmissible, we will not be surprised that graver moral defects are passed on. The grandson of a thief began to steal at three years of age, and at fourteen was an expert pickpocket. The police records show the same family names recurring year after year.
These cases are so grave as to attract attention, while we overlook the fact that the smaller immoralities are as apt to be transmitted, and perhaps with increased power. I should be afraid that slight lack of strict integrity in the father might appear as actual crime in the son.