Investigation into the reality of time can be pursued within the ontological domain or it can also span human thought and natural language. I propose to approach time by correlating three domains of inquiry: metaphysical time, the human concept of time, and temporal reference in natural language, entertaining the possibility of what I call a ‘horizontal reduction’ and ‘vertical reduction’. I present a view of temporalityL/E as epistemic modality, drawing on evidence from the L domain and its correlates in the (...) E and M domains. On this view, the human concept of time is a complex, ‘molecular’ concept and can be broken down into primitive concepts that are modal in nature, featuring as degrees of epistemic commitment to representations of states of affairs. I present evidence from tensed and tenseless languages and point out its compatibility with the view of real time as metaphysical modality. (shrink)