Modal logic was originally introduced by C. I. Lewis in order to study the modes of being: necessity, possibility, contingency. Later it was generalized by others to formalize also other notions, for example, by A. N. Prior (tense logic), G. H. von Wright (deontic logic), J. Hintikka (epistemic and doxastic logic), and D. K. Lewis (logic of counterfactuals). In this talk I will suggest how an approach in this tradition may be applied also to the study of metaphors.