I always satisfy myself being in the field of science, with the reason, in my opinion, the main or ultimate aim of humans is to understand the "un-understood" matters (problems) of the universe. People can understand repairing dead bodies or getting their body parts repaired by any means of their scientific research (life time work). By this they can become immortal and continue unveiling the answers of, who we are? who made us? etc. I carry this as my motivation to be in science field. Some of them like to do work in the non-science fields, they will have their own motivation, I want to know their motivation and satisfaction? I want to know only those satisfactions which are of great intense than becoming immortal physically by their life time work, so that I can adopt them in my life. Thank you.