As we trace a chain of reasoning backward, it must ultimately do one of four things: (i) end in an unjustified belief, (ii) continue infinitely, (iii) form a circle, or (iv) end in an immediately justified basic belief. This article defends positism—the view that, in certain circumstances, type-(i) chains can justify us in holding their target beliefs. One of the assumptions that generates the epistemic regress problem is: (A) Person S is mediately justified in believing p iff (1) S has a doxastic reason q for p and (2) S is justified in believing q. Assumption (A) presupposes that reasoning is only justification transmitting, not justification generating. The article rejects (A) and argues that, in certain circumstances, reasoning itself is justification generating, even if that from which one is reasoning is not itself justified. It concludes by comparing positism with its infinitist, coherentist, and foundationalist rivals, acknowledging what is right about these other views.