The Green Revolution averted mass famine during the 20th century. The contraceptive pill gave women unprecedented freedom in planning their own lives. Both are widely recognised as scientific breakthroughs that transformed the world. But few know that those breakthroughs only happened when they did because of a philanthropist willing to take a risky bet on a new idea.Holden Karnofsky has been studying philanthropy’s biggest success stories because he’s Executive Director of Open Philanthropy, a major foundation which gives away over $200 million a year — and he’s hungry for big wins.In this conversation from 2018 Holden explains the philosophy of effective altruism and how he goes about searching for giving opportunities that can do the most good possible.Full transcript, related links, and summary of this interviewThis episode first broadcast on the regular 80,000 Hours Podcast feed on February 27, 2018. Some related episodes include:• #41 – David Roodman on incarceration, geomagnetic storms, & becoming a world-class researcher• #37 – GiveWell picks top charities by estimating the unknowable. James Snowden on how they do it.• #10 – Dr Nick Beckstead on how to spend billions of dollars preventing human extinctionSeries produced by Keiran Harris.