From the entry on ‘humour’ in The Oxford Companion to Philosophy;
Amongst the topics that have surfaced in recent discussions, three catch the attention. We talk of a sense of humour, and this seems to assume that some are equipped to see what is funny about a situation whilst others cannot. Does it follow that the situation is itself funny antecedent to anybody finding it so? Are we then committed to realism about humour? Secondly, is humour a virtue? How does a sense of humour connect with other virtues, and is its absence a defect in an otherwise good person? Connected with both these issues is the general relevance of moral considerations to humour. Does the fact that a joke is racist or sexist mean that it is not really funny, or that it is merely a fault in us if we laugh at it?