The stomach and other hidden parts of the body have automatic functions independent of the will that perform digestion; these functions are beyond the scope of control, and hence means of preventing ill-digestion must be studied by the aid of the exterior sensations.
Sight, Appetite, Touch and Taste are the senses useful in selection of food and in the prevention of indigestion.
Sight and Appetite relate to invitation and selection, while Touch and Taste are discriminators and indicators of conditions.
Appetite and Taste are the sense functions that are most important to health, and hence they are the most important to study and understand. They are the guide in nutrition and the guard of the body machine--the Mind Power-Plant.
Smell also is an important aid in selection and discrimination and is an effective assistant of Appetite.
Appetite should be dignified and recognised as a distinct sense.
Normal Appetite is Nature's means of indicating her fuel and repair requirements for the Mind Power-Plant.
Study Normal Appetite and heed its invitation. It prescribes wisely. Its mark of distinction, to differentiate it from False Appetite, is "watering of the mouth" for _some particular thing_.
False Appetite is an indefinite craving for _something_, ANYTHING! to smother disagreeable sensations and frequently is expressed by the symptom of "faintness" or "All-gone-ness." [Vide the "A.B.-Z. of OUR OWN NUTRITION."]
Taste is the chemist of the body; of the Mind Power-Plant. More correctly, perhaps, it is the report of a chemical process relating to nutrition.
Taste is an evidence of nutrition. While taste lasts a necessary process is going on.
Taste should, therefore, be carefully studied and understood.
Both Taste and Appetite differ in different individuals and in the same individual under different conditions of thought or activity.
Taste is also dependent on supply of the mouth juices usually called saliva, and these differ materially in individuals, necessitating self-study, self-understanding, and self-care to insure prevention of indigestion and disease.
The most important part of nutrition is the right preparation of food in the mouth for further digestion.
The most important discovery in physiology is the relation of compulsory or involuntary swallowing to the right preparation of food for digestion.