Warrant, Reasoning and Competence

Abstract

The purpose of this chapter is to provide a broad characterization of purportedly deductive reasoning as a source of warrant. A preliminary characterization of warrant by reasoning is provided on the basis of a couple of restrictions. On this background, I attempt to articulate a somewhat traditional view about the relationship between the form of reasoning and the warrant that a reasoner may obtain by reasoning. I formulate this view as a thesis, which I label “The Classical Biconditional” or (CB) for short. The thesis is, roughly, that purportedly deductive reasoning from warranted premises yields warrant if and only if the reasoning is valid. I reject both directions of (CB). However, I will only argue against the left-to-right direction that I label “(Validity Requirement).” To fix the target position, I will provide what I take to be the traditional rationale for upholding the principle (Validity Requirement).