ABSTRACT
Man, in respect to his body and his physiological functions, belongs to the animal kingdom. The functioning of the animal is determined by instincts, by specific action patterns which are in turn determined by inherited neurological structures. The higher an animal is in the scale of development, the more flexibility of action pattern and the less completeness of structural adjustment do we find at birth. In the higher primates we even find considerable intelligence; that is, use of thought for the accomplishment of desired goals, thus enabling the animal to go far beyond the instinctively prescribed action pattern. But great as the development within the animal kingdom is, certain basic elements of existence remain the same.
