I defend a conception of Logic as normative for the sort of activities in which inferences super-vene, namely, reasoning and arguing. Toulmin’s criticism of formal logic will be our framework to shape the idea that in order to make sense of Logic as normative, we should con-ceive it as a discipline devoted to the layout of arguments, understood as the representations of the semantic, truth relevant, properties of the inferences that we make in arguing and reason-ing.

I distinguish four current strategies for integrating a rhetorical perspective within normative models for argumentation. Then I propose and argue for a fifth one by defending a conception of acts of arguing as having a rhetorical dimension that provides conditions for characterizing good argumentation, understood as argumentation that justifies a target-claim.

Grennan bases his evaluation of arguments on two criteria: logical adequacy and pragmatic adequacy. He asserts that the common formal logic systems, while logically sound, are not very useful for evaluating everyday inferences, which are almost all deductively invalid as stated. Turning to informal logic, he points out that while more recent informal logic and critical thinking texts are superior in that their authors recognize the need to evaluate everyday arguments inductively, they typically cover only inductive fallacies, ignoring the inductively (...) sound patterns frequently used in successful persuasion. To redress these problems, Grennan introduces a variety of additional inductive patterns. Concluding that informal logic texts do not encourage precision in evaluating arguments, Grennan proposes a new argument evaluation procedure that expresses judgments of inferential strength in terms of probabilities. Based on theories of Stephen Toulmin, Roderick Chisholm, and John Pollock, his proposed system allows for a more precise judgment of the persuasive force of arguments. (shrink)

I argue, contrary to a recent assertion by Lilian Bermejo-Luque, that the inference-claim in an argument of the form ‘p, so q’ is not its associated material conditional ‘if p then q’. Rather, it is the claim that the argument has a covering generalization that is non-trivially true. I defend this interpretation against three objections by Bermejo-Luque.