Abstract
One classical version of cosmological argument, defended famously by Thomas Aquinas and Duns Scotus, deduces the existence of a First Cause from the existence of a particular sort of causal series: one that is ‘essentially ordered’. This argument has received renewed defence in recent work by Feser, Cohoe, and Kerr. I agree with these philosophers that the argument is sound. I believe, however, that the standard defence given of the ECA in these philosophers can be complemented by a formulation that appeals to the powers theory of possibility. This approach to possibility has been defended in recent years by, for example, Pruss, Jacobs, and Vetter. In this article, I show how this modal theory allows us to defend the ECA in a way that is dialectically advantageous as well as clarifying.