For example, the “hydraulic model” of aid – the idea that if we simply pumped in more aid, better results would gush out – ignores the fact that funds are often fungible. Even if aid is narrowly targeted at say, food or health, a government can simply economize on expenditures that it might have made anyway and redirect them elsewhere – for example, to the military.
迪顿接着对目前最受追捧的流行改善援助手段提出了启发性的批评。比如说，援助的“液压模式”——所谓只要简单直接地提供更多援助，就能挤压出更好的结果——却忽略了援助往往是可替换的事实。即便援助仅限于食品或者是医疗药品，受援地政府也可以直接节省下援助所产生的开支并将其转移到其他地方——比如军事用途。