Max Weber Protestant Ethic, and Karl Marx's Capital had a huge impact on me. If you read Marx with a critical critique you can see that he's laid out a fantastic framework on how capitalism works, I do disagree with his core premise (capitalism being bad) so I took it as a great way to understand how I could operate inside of a capitalist economy. Weber on the other hand shows you exactly how to get ahead in the world and was critical to me understanding how we reward value creators in western society.