The son, the friend and the instuctor are all the same person, I, but of different versions in different environemnts. We change as the environment changes, in order to accommodate ourselves to it. We do this so naturally that we seldom notice doing it. Thus, a single adjective can never describe a person accurately on the whole, and in every environment. Altough the son, the friend and the instuctor are physically identical, they are very different in their behaviours.
Life is like a chemical system, in which equilibrium is never reached.
It is an opened system affected by external changes, such a the changes in the atmosphere, the temperature and many other factors of its environemnt. It is constantly shifting to a position which is best to it in the environment. Life is always changing, too. It changes so quickly that today, we may be quite different from who we were yesterday. Often, even we do not know ourselves, but merely our pasts.