First of all do it for yourself: achieving a PhD degree is basically the top of the academic world, if we are not talking about the Nobel Prize and such. PhD is giving major opportunities and although the chances are that you are going to stay in the world of academia for the rest of your life are big, but becoming a celebrity with tons of books written is also a possibility that you cannot deny. With a PhD you are welcome to any writing company that will easily grant you an above average middle class salary of six hundred thousand dollars. Sounds pretty good, don’t you think? Of course, starting your own business is also a good way of investing your knowledge.