According to wikipedia, Mental health is the level of psychological wellbeing or an absence of mental illness.It is the state of someone who is "functioning at a satisfactory level of emotional and behavioural adjustment". Simply summing up this all philosophy, according to our society if someone thinks and acts like everyone around him than that person is termed as a normal being otherwise that person is termed as mentally retarded. Acc. to a research a normal human brain works up to a capacity of 4-4.5% so if a person's brain works up to that capacity he will be termed as a normal human but if his brain works to a capacity of 7% and he acts curiously and asks uncommon question then he is termed as mentally ill. Don't beleive me. Wait I have many proofs. Starting from Albert Einstien , Thomas edison, Nikola tesla, stephen hawking etc.. and the list goes on. These were some of the personalities whose brain's usage capacity was More then 4.5% and hence they w...