For a small child, understanding the concept of time and its passage is very difficult. As a result, children are often impatient when expecting something or confused when trying to remember something from the past. They live in the present, and learn the notion of time only little by little. But accepting the passage of time, and the reality of aging, is something that plagues us even as adults. The lucrative cosmetic and plastic surgery industries show how humanity seeks to control or deny the passage of time, an urge that has proved to be relentless.