I think the majority of thoughtful people will agree that these words express their own observations. Every day we see how children have to be taught to act and behave. We see continually how parents have to put pressure on their children to make them accept and apply those moral principles and mental valuations which have guided their lives and the lives of thousands of generations before them. We know only too well that children do not inherit the moral standards of right and wrong of their parents, and that to establish these principles in the young is a matter of protracted and often painful inculcation. The proved maxim that honesty is the best policy is still being literally hammered into the children of to-day who seem to find it no easier to follow the better way than did the children of the past. If mental modifications acquired by the parents were in any degree transmissible to the offspring then there would be no need for this constant repetition of the same process in every new generation.
The earliest indubitable man hitherto discovered was fully evolved when first met with, he was _homo sapiens_. By means of his human intelligence this frail, unspecialized being became in a sense the very lord of creation, for instead of remaining, like the animals, entirely subject to his surroundings he subjected his surroundings to himself. By means of this intelligence man was enabled to break away from the absolute rule of the law of natural selection which punishes with extinction all those types that fail in fitness for survival in the struggle for existence, so that, unlike the animals that die out when their particular structure does not fit in with their environment, man by means of his thinking brain was able to equip himself with parts of his environment, and thus to become its master. The process of evolution ceased to affect directly this creature who had a brain that could think, and ever since that brain was given to him man has remained unmoved and stationary above and apart from all other living things. All this is implied in the command, "Be ye fruitful and multiply and replenish the earth and subdue it."
But though man became almost emancipated from the direct servitude of natural selection, he still is, and always will be, subject to the law of heredity. Man is made up of a group of innate characters inherited from a very mixed ancestry, these characters, being innate, are transmissible to his offspring, but such characters as are acquired by the parent through the direct influence of education or other environment, not being innate are not transmissible to his children. But in so far as a new development of latent and innate characters, through the influence of the environment, may help or hinder certain types in propagating themselves, the race may, perhaps, be modified through such influence by the process of gradual elimination of the types that lack the characters that prove to be of survival value in a particular locality. This we may suppose might happen where a number of Europeans, composed half of blondes and half of brunettes, come to live in a tropical country, if it be proved that the comparative darkness of the brunettes afford them better protection against inimical light and heat than the fair skin of the blondes, so that the former would on the average, enjoy better health and live longer, and therefore have more children than the latter, whereby, in course of time, the appearance of these people would be modified in respect of the general complexion of their skin. This, it is easy to see, would not mean the acquisition of a new and heritable means of protection, but only a development in each individual of an already present innate character that happened to be well fitted for survival in a certain climatic zone.