To understand this clearly we must bear in mind the principle which modern psychology is gradually adopting, that of the unity of the organism.
=The Organism is a Unit= which cannot, except for reasons of pure convenience, be split into entities of a contrasted character, such as body and mind, matter and soul, etc. To every physical phenomenon corresponds a simultaneous mental manifestation and vice versa. The body is the tangible aspect, the mind, the intangible aspect of the organism.
Nor can any scientific distinction be drawn between the so-called grossness of the body and the spiritual quality of the mind.
Nor can we establish in the body absolute lines of cleavage between the various organs, heart, stomach, liver or sexual organs. They are all closely interrelated and there again we find a profound unity of action. When the nerves of the "life division" of the autonomic nervous system are set working, the pupil will be contracted, the saliva flow, the heart beat more slowly, the stomach secrete gastric juice and churn food, the intestines push digested food toward the rectum, and the sexual organs fill up with blood.
When the "safety nerves" are in action the pupil is dilated, the saliva scarce, the heart beats faster, gastric activities cease or become reversed (vomiting), the intestines either stop their activity or are affected by diarrhea and the sexual organs are emptied of blood. Any stimulation applied to any of those organs will produce the specific stimulation indicated above in ALL THE OTHER ORGANS, tho in varying degrees.
In other words perfect peace and safety promote all the activities of the "life nerves," danger and fear promote all the activities of the "safety nerves." Peace and safety build up the body and assure the continuance of the race. Danger and fear stop all the activities which are not directly concerned with fight or flight, hence weaken the organism and stop the sex life.
Peace and safety represented by the mental and physical fetishes of the mate toward whom we are driven by an organic compulsion are bound to produce in us most gratifying results.
The sight, smell and taste of good food, the sight of pleasant objects, the sound of good music, etc., produce a powerful stimulation.