The founding claim is empirical and narrow, which is what made it persuasive: charitable interventions vary in cost per unit of benefit by factors of ten or a hundred, the variation is measurable, and therefore choosing well matters more than giving more. GiveWell, founded in 2007 by two former hedge-fund analysts, built the methodology; the movement built the ethics on top of it. The obvious criticism is that measurability selects for the interventions that happen to be easy to count — bed nets and deworming rather than institutions, politics or the slow work of building state capacity — and effective altruists have argued about this internally for fifteen years without settling it. The movement's own front page still states the commitment as using reason and evidence to find the most effective ways to help others.