Suggestion directly and spontaneously affects the psychic sphere of another person through directive or argument, through compelling and agitated speech, through gestures, mimicry, movements and signs, or other symbols. It is obvious from the preceding that both imitation and suggestion on the one side and persuasion on the other are basic ways for one person to influence another. Nevertheless, at least in some cases, a directive, like a suggestion, affects the psychic domain directly. As well, advice, wishes, and other forms of influence of some people on others can also affect the mind, either in the form of suggestion or in the form of argument, depending on the aim of the person expressing them. In addition, suggestion or induction of ideas plays a considerable role among the populace, substantially influencing the world view of individual persons and even of whole societies. Even science is not an exception from the general rule; it, too, employs suggestion and mutual suggestion.