Arguments figure prominently in our practices of reason-giving. For example, we use them to advance reasons for their conclusions in order to justify believing something, to explain why we believe something, and to persuade others to believe something. Intuitively, using arguments in these ways requires a certain degree of self-reflection. In this paper, I ask: what cognitive requirements are there for using an argument to advance reasons for its conclusion? Towards a partial response, the paper’s central thesis is that in (...) order to so use an argument one must believe the associated inference claim to the effect that the premises collectively are reasons that support the conclusion. I then argue against making it a further cognitive requirement that one be aware of one’s justification for believing such an inference claim. This thesis provides a rationale for the typical informal-logic textbook characterization of argument and motivates a constraint on adequate accounts of what are referred to as inference claims in the informal logic and argumentation literatures. (shrink)