It is not good to have a thinking of pessimism, but in this world many people are pessimists who are forced to be pessimistic by the circumstance they face. Those groups belong to the unsuccessful middle aged men, retired persons, old people, crippled ones, sick patients. Most of them are pessimistic, rare optimistic.
Once a man reaches his age at forty and he is nothing achieved, he will certainly incline to be pessimistic. According to statistic, a person over forty will be difficult to compete against ages around thirty.
Most retired people are pessimistic. It is because that before their retirement, they were so powerful that many people had to take orders from him, but once he retired, no one will listen to him. He is lost in the memory of past world.
Almost every old man is pessimistic which is normal from realistic point of view. Old man knows that his days in this world is getting less and less. He cannot travel, unable to bear the journey of different countries. He cannot eat expensive foods which mostly belong to the undigested group. He cannot have a high quality sleep in the night, leading him to be tired all the day. Besides, he is frequently visited by all sorts of illness which, even he paid a lot of money, doctor still cannot cure. Therefore, he is helpless to face the day of every day.