Although the headline of this post is focused on reading and puts the emphasis on children, to whom we will refer at the end, everything that follows is applicable to any habit and person, so do not stop reading it, because it is extremely interesting . Best CBSE Schools in Coimbatore. Maxwell Maltz was a plastic surgeon in the 1950s when he began to notice a strange pattern among his patients… When Dr. Maltz performed an operation, like a nose job, for example, he found that it took the patient about 21 days to get used to seeing his new face. Similarly, when a patient had an arm or leg amputated, Maxwell Maltz noted that the patient felt a phantom limb for approximately 21 days before adjusting to the new situation. These experiences led Maltz to think about his own period of adaptation to changes and new behaviors, noting that it also took around 21 days to acquire a new habit. Maltz wrote of these experiences, saying, "These and many other commonly observed phenomena tend to show that a minimum of about 21 days is required for an old mental image to dissolve and a new one to solidify." In 1960, Maltz published that quote and his other thoughts on behavior change in a book called Psycho-Cybernetics. The book became a box office success, selling over 30 million copies.