 For Hartley, complex and decomplex ideas are wholes that do not “bear any relation to [their] compounding parts.” Specifically, “the decomplex idea belonging to any sentence is not compounded merely of the complex ideas belonging to the words in it” (OM 1, prop. 12). The meaning of an utterance is a property of the whole—of the performance of a specific decomplex action in a social and pragmatic context. Moreover, “both children and adults learn the ideas belonging to whole sentences many times in a summary way, and not by adding together the ideas of the several words in the sentence.” Consequently, children and illiterate adults find it hard to “separate sentences into the several words which compound them” (OM 1, prop. 80).