Note muddle about one Aristotelian literary term (7)

'aristotelian literary term' is the definition.
The answer and definition can be both related to thinking as well as being singular nouns.
Maybe there's an association between them I don't understand?

'note muddle about one' is the wordplay.
I cannot really see how this works, but
'note' could be 'si' (I've seen this in other clues) and 'si' is located in the answer.
'one' could be 'me' (a setter might use 'one' to humourously mean 'me') and 'me' is located in the answer.
The remaining letters 'mis' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?