The popularization of bacteriology, then, has been one of those moments of unfavorable suggestion that have affected a large number of people. Such influences do not mean much for people of phlegmatic temperament. For others, however, they have a weighty significance and make every symptom, or more properly every sensation, that is at all unusual in the digestive tract, seem of ominous import. Certain sensations inevitably accompany digestion. The peristaltic movements are usually said to be unfelt, but even a slight exaggeration brings them into the sphere of sensation. Where attention is given to the abdominal region and its contents, feelings that ordinarily are not noticed at all come to be perceived. With the unfavorable suggestion derived from the unfortunate diffusion of a superficial knowledge of pathology and of bacteriology instead of hygiene and the science of beneficent microbiology, these feelings produce a bad effect upon the individual. Familiar Examples of Unfavorable Suggestion.--There are many familiar examples of the discomfort that may be produced by the mental persuasion that something will disagree with us, or that certain feelings have a significance quite beyond that which ought to be attributed to them. Everyone knows how qualmy may be the feeling produced by being told that something eaten with a relish contained some unusual material, or was cooked under unclean conditions. Food that agrees quite well with people, so long as they do not know too much about it, often fails to be beneficial after they see how it has been prepared. It is often said that people would not relish the food {97} placed before them if they were aware how lacking in cleanliness was the place of its preparation, and how negligent those who had charge of it. Occasionally a peep at the kitchen of a boarding house effectually takes away appetite, or disturbs the equanimity with which food must be taken, if there is to be that undisturbed digestion which makes for healthy nutrition. It is, indeed, with regard to digestion that the influence of the mind on the body, favorable as well as unfavorable is, perhaps, most effectively exercised. Unfortunately the unfavorable influence is even more pronounced than its opposite. Some people are much more sensitive than others in this respect, and even the thought of certain defects in the preparation of their food seriously disturbs them. Everyone has had the experience of seeing sensitive persons leave the table because some one insisted on telling a nauseating tale. Anyone who has seen the effect of talking of blood sausage or fried brains with black butter sauce at a table on shipboard, when some practical joker was exercising his supposed wit, knows how much the imagination can disturb, not only appetite but digestion. The attitude of mind means much, and especially are such unfavorable suggestions likely to produce serious effects in inhibiting digestion.