If S reasons as if she possesses a different concept (e.g., ancient rather than arcane), it follows not that she misuses a concept but that she has another concept.

This argument runs parallel to the argument from understanding in support of ME normativity (section 2.1.2). Even if that argument is accepted, however, the question arises whether it can be applied to concepts and content, since the notion of failing to use a concept in “keeping with its content” appears more problematic than the notion of failing to use a word in accordance with its meaning (McGinn 1984: 146–147; Millar 2004: 180–181). It is relatively unproblematic to speak of understanding