Taxonomies of the passions have long claimed to serve a quest for self-knowledge, by specifying conditions under which certain passions arise, formal objects they possess, and qualities essential to their particular feelings. I argue that David Hume's theory of the passions provides resources for a different kind of self-knowledge – a sceptical self-knowledge depending on our ability to articulate how the passions feel rather than always identifying our passions as tokens of an identifiable passion-type. These resources are distinctions between four (...) qualitative aspects that passions may possess – pleasantness or painfulness, calmness or violence, invigoration or softening, and directedness or lack thereof towards specific actions. Reflection on these aspects produces a more accurate understanding of the nature of our emotions and chastens our judgmental tendencies in ways that benefit both self and others. (shrink)