We shall investigate the similarities and dissimilarities between old and new dialectic. For the ‘old dialectic’, we base our survey mainly on Aristotle’s Topics and Sophistical Refutations, whereas for the ‘new dialectic’, we turn to contemporary views on dialogical interaction, such as can, for the greater part, be found in Walton’s The New Dialectic. Three issues are taken up: types of dialogue, fallacies, and strategies. Though one should not belittle the differences in scope and outlook that obtain between the old (...) and the new dialectic, the paper will show that in many respects the old dialectic foreshadows the new dialectic. (shrink)

How do, according to Aristotle, peirastic arguments, which are employed by nonscientists to put professed scientists to the test, work, and how do they differ from genuine scientific arguments? A peirastic argument succeeds in unmasking a would-be scientist if it establishes an inconsistency among the answers given. These answers may only comprise: propositions which are proper to the field and which everybody can know; propositions which only scientists may know; “common” propositions that everybody, including various sciences, uses in all kind (...) of arguments. On the other hand, a peirastic argument fails to do its job if it either features or presupposes in addition propositions which would justify a fallacy, or if it purports to be scientific. The latter type of bad peirastic argument crucially depend on common propositions where scientific arguments explain by reference to combinations of the primitive items of the science in question. (shrink)

In Sophistical Refutations 8 Aristotle claims that every sophistical refutation depends on a false belief which is implicitly held by the victim of the fallacy and can normally be elicited from him as an explicit additional premiss. In this case the fallacious argument will be turned into a valid one, albeit with a false premiss. The paper discusses the nature of the FVP and tries to discover how it works when it tacitly causes the false appearance of a fallacious argument.