 As we have seen in  section 2,  some reject Hume’s claim that all inductive inferences presuppose the UP. However, the argument that basing the justification of the inductive inference on a probable argument would result in circularity need not rely on this claim. The circularity concern can be framed more generally. If argument S relies on something which is already presupposed in inference X, then argument S cannot be used to justify inference X. The question though is what precisely the something is.