Suggestion
in psychology, may be defined as including all proposals to action or belief put into the mind of one person by another and which overcome resistance not by argument or reason, but by submission or subordination, whether conscious or unconscious, on the part of the recipient. Every human being is to some extent subject to the influence of others' suggestions, which may be communicated in numberless ways, as by spoken words or by subtle indirection, probably most commonly without intention. The explanation of this wide suggestibility is that the majority of our motives and actions are the outcome of numerous contending impulses which are often not unequal in their strength or weakness, so that if one is strengthened for a moment it may achieve complete preponderance.
Otherwise the tendency to yield to suggestion resembles the instinct of imitation. It varies widely in different persons as well as under different conditions. Periods of emotion or fatigue or illness are highly favorable to suggestibility, which may also be increased by alcohol or drugs or by feelings of confidence, awe, or fear inspired by some person. The suggestibility of crowds is notorious, as is that of children and of persons on the witness stand.