Conceptual Metaphor Theory makes some strong claims against so-called Classical Theory which spans the accounts of metaphors from Aristotle to Davidson. Most of these theories, because of their traditional literal-metaphorical distinction, fail to take into account the phenomenon of conceptual metaphor. I argue that the underlying mechanism for explaining metaphor bears some striking resemblances among all of these theories. A mapping between two structures is always expressed. Conceptual Metaphor Theory insists, however, that the literal-metaphorical distinction of Classical Theories is empirically wrong. I claim that this criticism is based rather on terminological decisions than on empirical issues. Conceptual Metaphor Theory focusses primarily on conventional metaphors and struggles to extend its mechanism to novel metaphors, whereas Classical Theories focus on novel metaphors and struggle to extend their mechanisms to conventional metaphors. Since all of these theories study metaphors from the synchronic point of view, they are unable to take into account any semantic change. A diachronic perspective is what we need here, one which would allow us to explain the role of metaphor in semantic change and the development of language in general.