Abstract
This paper is about the relationship between actuality and potentiality. Two paradigms are considered: Leibnizian possible worlds, which is rooted in classical physics; and the consistent histories quantum theory of Griffiths, Gell-Mann, Hartle, and Omnès. I explore an interesting connection between these two paradigms. The analysis goes beyond a comparison of classical and quantum physics to consider how modern physics might be integrated into a more comprehensive view of the world, in the spirit of Leibniz’s own philosophy.