Supposition and Blindness

In ‘Reasoning and Regress’ I argued that inferring a conclusion from a set of propositions may simply consist in taking it that the conclusion follows from these propositions—thereby defusing familiar regress arguments. Sinan Dogramaci challenges the generality of this view, on the grounds that sometimes (specifically, in cases of suppositional reasoning) you may draw conclusions from no premisses that you believe. I respond by clarifying a distinction between the premisses of an argument (conceived of as a certain formal structure) from the reasons your conclusion is based upon. While suppositional reasoning may involve no premisses in the former sense, it does not follow that it does not involve concluding something on the basis of reasons. This allows the view defended in ‘Reasoning and Regress’ to extend to suppositional reasoning.