ABSTRACT
In this concluding chapter, we will once more deal with human beings. I have often had to mention them before, and I believe that we have been able to show very many traits common to man and animals. I do not of course intend to eliminate the difference between man and animals; the zoologist is perhaps of all men the most familiar—almost daily and hourly in fact—with the line of division between animals and man. But we must not forget, by reason of the differences, what they have in common; and it must be especially stressed here that man can never be completely understood as a “spiritual being”; if no account is taken of the fact that he is conditioned by, and bound to, nature, he easily becomes for the investigator a ghost and a phantom.
