In this overview article, we first explain what we take informal logic to be, discussing misconceptions and distinguishing our conception of it from competing ones; second, we briefly catalogue recent informal logic research, under 14 headings; third, we suggest four broad areas of problems and questions for future research; fourth, we describe current scholarly resources for informal logic; fifth, we discuss three implications of informal logic for philosophy in particular, and take note ofpractical consequences of a more general sort.

I argue in a non-reductive sense for a plausible epistemic principle, which can (1) theoretically and instrumentally unify or systematize all fallacies, and (2) provide a justification for using such a principle for characterizing an erroneous argument as a fallacy. This plausible epistemic principle involves the idea of an error in the method of justification, which results in a failure to provide relevant evidence to satisfy certain standards of adequate proof. Thus, all fallacies are systematically disguised failures to provide substantive (...) proof: a failure in the attempt to persuade rationally, as opposed to emotionally or rhetorically. I argue that the epistemic idea of begging the question is essential to this idea of a fallacy as an inadequate proof. (shrink)

A simple way to approach fallacies is to ask, "Has reasoning-strategy X retarded or halted the growth of knowledge?" and seek uncontroversial historical events as empirical support for the fallacy moniker. Historical support also offers a means of retiring reasoning strategies heretofore thought fallacious—they are wrongly accused if they helped drive knowledge. Finally, this approach allows us to be more critical of our argumentative practices. Evidence is offered for an Intuitive Fallacy: In its extreme form it rules out the possibility (...) of evidence; in its weaker form, it is a non-response to evidence that appears to be a response. (shrink)