Life is nothing but different stages just like games, where some stages just pass away even before you acknowledge them and some stay for longer. Every stage gives us either happiness or sorrow as a reward and a choice, our actions are the choices we make. Each action leading us to either of the reward. Sometimes we learn to make right choices and sometimes the right choices leads us to wrong place, that is the unexpected reward. All right choices does not have to give happiness and all wrong choices doesn't have to give sorrow. In between all of this chaos we find ourselves in need of so many other emotions which are interlinked sentiments which finally leads back to the same two emotions that is either happiness or sorrow. So these interlinked emotions are the reactions after each choice we make and finally making us what we are.