At the age of 26, in the early 1970s, Ronald Cohen co-founded Apax Partners, one of the world’s oldest venture-capital firms. It was around the same time that Milton Friedman famously wrote that the social responsibility of a business is to increase profits. That was a premise Cohen rejected even as he built his fortune; he felt, instead, that capital could produce solutions to pressing problems.

“Without him, we wouldn’t have impact investing at all,” says Fiona Reynolds, CEO of Principles for Responsible Investment. “He has worked tirelessly to make sure that government understands the benefits.”

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