Philosophy books for decision theory and economics idea I have learned economics so far, the most astonishing economics' thing is its though which is talkable and visually in the real world or the abstract world that is worth researching and talking. What I see in common is the abstract ideas that are generated from philosophy and economics is the social science study, I am interested in both philosophy and economics but what I only know and read is economics' side, not philosophy's side.

Does anyone recommend any book worth for spending the time to gain both sides of knowledge?
Your question is a little bit unclear. But still, if you wish to delve into the philosophical side of economical topics/question/phenomena, you can check the Stanford Encyclopaedia of Philosophy's article on Philosophy of economics. It might be a good place to start and refine what you are looking for.