This page has been validated.
IX.
THE AXIOM OF SCIENCE.
THE fundamental law, without whose observance reliable biological investigation is impossible, is stated as follows:
'In studying the laws alike of organic and of inorganic Nature, the experimenter must be careful not to destroy the phenomenon that is being investigated.'
Intellectual error, as well as practical danger, arises from the attempt to transfer to man results supposed to be gained by fallacious experimentation on the lower animals. The fallacy consists in noting general resemblance of structure, but not the far more remarkable differences of function. If, for instance, the life-habits of two dogs of good breed are closely studied, it will be seen that, although certain individual differences are
