The social intuitionist approach to moral judgments advanced by social psychologist Jonathan Haidt presupposes that it is possible to provide an explanation of the human moral sense without normative implications. By contrast, Iris Murdoch’s philosophical work on moral psychology suggests that every description of morality necessarily involves evaluative features that reveal the thinker’s own moral attitudes and implicit philosophical pictures. In the light of this, we contend that Haidt’s treatment of the story about Julie and Mark, two siblings who decide to have casual, protected, and in his view harmless sex, provides a too simplistic picture of what is involved in understanding human morality. Despite his aim to explain the roots of moral judgments, he fails to provide a deeper understanding of morality in two different respects. First, he does so by suggesting that his story contains all the relevant information needed to take a moral stand on it, and by rejecting as irrelevant the wider human context in which questions about sexual and family relations arise. Second, he simplifies the responses of the people who are subject to his experiment by disregarding their various reasons for disapproving and by equating understanding human morality with explaining an impersonal psychological process.