 To resume: ideas with different content also differ. Once again, however, this condition is merely sufficient, as the same parts can be arranged differently, witness: [ignorant son of a learned father], [learned son of an ignorant father]. Accordingly, Bolzano recognizes the structure of a complex idea, the way its parts are combined (their Verbindungsart), as an additional individuating attribute. Indeed, sometimes structure is the only individuating attribute, as Bolzano shows in TS (§96, no. 2) with the clever example of [\(2^{4}\)] and [\(4^{2}\)], which have the same content and the same extension but differ nonetheless.