How did the system of patents encourage innovation and investment?

Patents give the inventor or patent holder rights to profit off of their creations. If no patent system were in place, there would be less incentive for inventors to invest time and money in research and development. Inventors don't want to invest a lot of their resources to invent something that someone else can profit from. So a system of patents allows people to profit off of their innovations without having to worry about someone else stealing their ideas.