The truth of this inference cannot be denied, because to leave out of view considerations of sentiment and morality would fatally vitiate any scheme for the improvement of the human race. But Professor Jowett affirms that, "We do not know how by artificial means any improvement in the breed can be effected." The problem is no doubt a complex one. As he points out, a child has usually thirty progenitors only four steps back, and whatever truth there may be in the inheritance of special physical characters, "We have a difficulty in distinguishing what is a true inheritance of genius or other qualities, and what is mere imitation or the result of similar circumstances. _Great men and great women have rarely had great fathers and mothers._" Professor Jowett thinks, indeed, that too much importance may be ascribed to heredity. He says: "The doctrine of heredity may seem to take out of our hands the conduct of our lives, but it is the idea, not the fact, which is really terrible to us. For what we have received from our ancestors is only a fraction of what we are or may become. The knowledge that drunkenness or insanity has been prevalent in a family may be the best safeguard against their recurrence in a future generation. The parent will be most awake to the vices or diseases in his child of which he is most sensible within himself. The whole of life may be directed to their prevention or cure. The traces of corruption may become fainter, or be wholly effaced; the inherited tendency to vice and crime may be eradicated. And so heredity, from being a curse, may become a blessing. We acknowledge that in the matter of our birth, as in our nature generally, there are previous circumstances which affect us. But on this platform of circumstances, or within this wall of necessity, we have still the power of creating a life for availment by the reforming energy of the human will." There is much truth in these remarks of Professor Jowett, but they do not affect the argument in favor of the possibility of bringing about an improvement in the race if the proper means are adopted. It would not be any wiser for the strong and healthy to marry with the sick and weak, because the latter happen to be highly intellectual or moral, than to marry with the strong and healthy if these physical characters are united with mental weakness or immorality. There is a consensus of opinion at the present day, that what should be aimed at is the union of physical perfection with that of intellect and character, in the persuasion that steps towards this end will ultimately lead to the general improvement of the human race.