Moral judgements reflect default representations of possibility.

Moral judgement requires representing what is possible: judging that someone ought to do something implies that they actually can do that thing; and if they cannot do that thing, then it is not the case that they ought to have done it. Moral judgements are often made quickly and effortlessly, suggesting that they may rely on default, rather than deliberative, representations of what is possible. To investigate this possibility, we asked participants to make 10 different kinds of moral judgements either very fast or more slowly about 240 different actions across 12 contexts. We found that these moral judgements were more similar to one another when participants were forced to quickly assess the morality of immoral actions, suggesting a common default template for moral judgement that becomes more differentiated upon reflection. When making moral permissibility judgements quickly, participants were more likely to judge that improbable, irrational and impossible actions were not permissible, indicating that default representations of permissibility may be reflecting default representations of possibility. A direct investigation revealed a close relationship between default representations of possibility and fast judgements of moral permissibility. These findings demonstrate the role of default representations of possibility in moral cognition. This article is part of the theme issue 'Thinking about possibilities: mechanisms, ontogeny, functions and phylogeny'.