Edward Westermarck,
The History of Human Marriage
“ If we want to find out the origin of marriage, we have to strike into another path, the only one which can lead to the truth, but a path which is open to him alone who regards organic nature as one continued chain, the last and most perfect link of which is man. For we can no more stop within the limits of our own species, when trying to find the root of our psychical and social life, than we can understand the physical condition of the human race without taking into consideration that of the lower animals. ”
