It has generally been assumed that, since the term "literal" distinguishes productive uses of words from idiomatic uses, non-metaphoric from metaphoric, and direct from indirect, that literal meanings must be the same as sentence meanings, i.e., that they could be computed from knowledge of the words and core grammar rules of the language.

However, this widespread presupposition appears to be false. In particular, literal interpretations of a sentence, even out of context, generally make recourse to extra-linguistic knowledge, while some non-literal interpretations are purely linguistic in nature. Furthermore, the semantic content derivable from purely grammatical and lexical knowledge may not even be a possible interpretation of a sentence.

Since these distinctions are hopelessly misleading, a new set is proposed based on a very different organization of knowledge. "Primal content" refers to the interpretation we can assign to a sentence based on lexical and grammatical knowledge, broadly construed. "Actual content" refers to the specific meanings speakers encode into utterances and extract out of utterances, generally making liberal use of extralinguistic facts. The resulting dichotomy is meant to provide a firmer basis for theorizing about meaning.