it is human nature to seek morc and to want something different. there are many instances in our daily life that can verify this.

　　we can take some human's basic needs as an example we do not want to wear the same clothes all the time and we want better and better cars. we wish to live in a more spacious flat. of course not all human beings are the same. for instance, some people try to climb up socially or politically all the time, while others never stop trying to make more money. children long for new toys while the old hope to live longer. scientists want to make new discoveries while writers desire to produce more works.

　　good or had, this human nature has been the impetus to the de velopment of human society. markets flourish because we want more and better goods. the development of science and technology has never stopped because of our desire to discover more and more. if man has been easily satisfied, the human society would still be at its primitive stage.