This paper explores reasoning about space and time, e.g., in metaphors of time as space; an important method is to find minimal assumptions needed to reach the same conclusions that humans reach. Some mathematical language is introduced for this purpose, which formalizes and generalizes the cognitive linguistic approaches to conceptual spaces, blending, and metaphor, in particular using continuous mathematics to talk about space and time. A new explanation of emergent structure in blend spaces is also discussed, and proposed as a source of creativity. (Joseph A Goguen)