A woman describes recurrent thoughts of contamination that she finds distressing, but on further questioning she says she is not actually sure the thoughts are irrational — she feels genuinely convinced her hands are contaminated no matter how much she washes them, and this conviction does not waver even when shown clear evidence otherwise. Before revealing the answer: is this a straightforward obsession?

Not straightforwardly. A core feature of an obsession is that the person retains insight that the thought is excessive or irrational, even though they cannot easily dismiss it. Here, her conviction appears fixed and unresponsive to evidence, which raises the question of overvalued or even delusional-level conviction rather than typical obsessional insight. This does not necessarily mean she does not also have obsessional features, but it means insight should be assessed explicitly and not assumed, since the degree of retained insight is exactly what a straightforward obsession requires and what distinguishes it from more fixed, delusion-like conviction.