 The introduction of principle-dependent desires bursts any would-be naturalist limit on their content; nonetheless, some philosophers hold that this notion remains too beholden to an essentially Humean picture to be able to capture the idea of a moral commitment. Desires, it may seem, remain motivational items that compete on the basis of strength. Saying that one’s desire to be just may be outweighed by one’s desire for advancement may seem to fail to capture the thought that one has a commitment – even a non-absolute one – to justice. Sartre designed his example of the student torn between staying with his mother and going to fight with the Free French so as to make it seem implausible that he ought to decide simply by determining which he more strongly wanted to do. 