 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 the meaning of an expression (or misunderstanding it), but in the case of concepts there is nothing corresponding to the expression. To “understand” a concept is simply to possess it, to use it in thoughts. Hence there seems to be little or no room for the idea that \(S\) misunderstands a concept either. If \(S\) reasons as if she possesses the concept ancient rather than the concept arcane, it would seem to follow not that there is any misuse of concepts but that she has another concept.