Boris Sidis

“ The supreme importance of pathological research holds especially true in the case of psychology, where the phenomena and the conditions on which these depend are so highly complex and so intricate, appearing at the same time so simple and taken as a matter of course in ordinary life.
As we have pointed out in the investigation of mental life we may either change the psychic or objective content, or effect changes in the mental function itself. In the study of vision, for instance, we may effect changes in the conditions of external objects, leaving the eye itself undisturbed. ”

“ We all know how valuable the observation and study of all forms of anomalies or variations from the normal type or species proved to the final establishment of the theory of evolution. The pre-Darwinian zoologist ignored variation regarding it simply as an exception to the normal, as a mere abnormality, as a pathological manifestation which is of little value to the scientist, who is only occupied with the discovery of general laws, laws of the normal. ”

“ The psychologist in order to succeed and obtain more efficient and valuable results must keep in mind clearly the fact that the psychic process is a form of life in general, its phenomena are naturally related to the province of biology, and that of the highest part of it. The methods of psychological investigation must follow the line not of the physical, but of the biological sciences. ”

“ Experiments on animals such as vivisection, injecting of toxin matter, etc., experiments that actually mean the putting of animals in pathological states, as well as the investigation of pathological cases in man, have given physiology its most valuable treasures. Knowledge of the normal arises out of knowledge of the abnormal. ”

“ If we turn to the sciences dealing with more complex phenomena, we find illustrated the same truth. We know how highly instructive Darwin found it to follow closely for a period of many years experiments of breeds in artificial selection, and to what capital account he turned his highly valuable observations of all forms of curiosities and monstrosities. ”

“ The ancients who looked to the ordinary phenomena of common life, that is to the normal, considered that bodies are bound to stop. The ancient physicists, relying on their observations of the normal, believed that bodies in falling traverse space in proportion to their weight ”