In his recent article, “Everything is Conceivable: A Note on an Unused Axiom in Spinoza's Ethics”, Justin Vlasits carefully analyzes parallels between the first four propositions of the Ethics and Spinoza’s correspondence with Henry Oldenburg to argue that Spinoza intended to appeal to E1A2 in E1P4dem of the Ethics. In this short response, I identify a problem with Vlasits’ analysis. Vlasits insists that the scope of E1A2 is not determined by what is conceivable, and I show that this creates a (...) logical lacuna within his reconstructions of Spinoza’s arguments for the claim that “outside the intellect there is nothing except substances and their affections”. However, I show that on the conceivables interpretation of E1A2 that Vlasits' rejects, Spinoza’s argument for this claim goes through. While my analysis undermines Vlasits' attempt to identify the role of E1A2 in the Ethics, it sheds substantial light on this axiom, and shows how conceivability and being are intertwined in Spinoza’s thought. (shrink)