If we think of fallacies as violations of the preconditions governing the products, processes, and procedures of argumentation, we see that fallacies do not merely weaken arguments, but rather undermine the possibility of argument itself. This approac h recommends itself on several counts. First, it accounts for diversity in fallacy analysis. Second, it makes possible investigations into new kinds of fallacies. Third, it provides new applications for ongoing developments in fallacy theory.