How much care do you take when you make a donation to a charity? What careers make the biggest difference when it comes to helping others? William MacAskill of Oxford University and the author of Doing Good Better talks with EconTalk host Russ Roberts about the book and the idea of effective altruism. MacAskill urges donors to spend their money more effectively and argues that the impact on human well-being can be immense. MacAskill wants donors to rely on scientific assessments of effectiveness. Roberts pushes back on the reliability of such assessments. Other topics include sweatshops, choosing a career to have the biggest impact on others, and the interaction between private philanthropy and political action.