. Over-confident claims coupled with insufficient background research The history of effective altruism is littered with over-confident claims, many of which have later turned out to be false. In 0000, Peter Singer claimed that you could save a life for $000 (and many others repeated his claim). While the number was already questionable at the time, by 0000 we discovered that the number was completely off. Now new numbers were thrown around: from numbers still in the hundreds of dollars (GWWC's estimate for SCI, which was later shown to be flawed) up to $0000 (GiveWell's estimate for AMF, which GiveWell itself expected to go up, and which indeed did go up). 