by Dr. Napoleon Hill
Here you have a most profound principle; in fact, the master principle through which all natural phenomena are expressed; the power through which all the sciences are relentlessly carried out with invariable certainty; the principle which perpetuates the species of every living thing, causing each to adapt itself to its environment; the principle which fixes the thought habits of man so definitely that man is ruled by his habits.
There are only three principles underlying the voluntary establishment of a habit. They are very important, so remember them well:
A. Plasticity, which is simply the property or capability of changing or being changed. It also implies that once a change has been made, the new form established remains until a subsequent change modifies it. In other words, plasticity is the sort of flexibility found in a piece of modeling clay used by children in school. It may be molded into any desired shape and it will remain in that shape until it is molded into a different shape. Man, of all living creatures, is the only one who possesses this characteristic of being plastic, of being capable of change, and his plasticity lies, of course, in his mental faculties. Man may be changed by external influences or his environment; or he may voluntarily change himself, by exercise of his will power. This prerogative obviously is a basic necessity for the formation of voluntary habits.
B. Frequency of impression. As we have seen, repetition is the mother of memory. It is also the mother of habits. One of the factors affecting the speed with which a habit can be established is how often the action or thought involved is repeated. This, of course, varies with the individual, the circumstances, and the element of time. A thought can be repeated only so many times a day, for instance, and if a man is at work, circumstances may prevent his thinking of the particular habit he wishes to establish. There is also the matter of personal initiative. A man may be lazy and indifferent, or he may be ambitious and energetic. This will affect the number of times he will repeat the action or thought. This, in turn, affects the length of time it will take him to establish the habit.
C. Intensity of Impression. Here is another variable in the process of establishing a habit pattern. All through these principles you have been told of the importance of a strong, compelling motive, and a burning desire, as essentials. Here is the reason. If an idea is impressed upon the mind, backed with all the emotion you are capable of, it will become an obsessional desire. Thus it will have a greater impact than if you simply express an idle wish, even though the words you employ are identical. The degree of intensity of impression is, therefore, another factor which affects the speed with which a habit may be developed and set.