Class of Arguments
A subargument is a subset of an argument consisting of statements that are used exclusively to reach a subconclusion.
A class of arguments is a set of arguments that differ only by the replacement of a subargument.
By replacing the subargument by its subconclusion, an infinite class of arguments is created that represents the set of all arguments that use any possible subargument for the given subconclusion. To verify that the infinite class is sound, one must find one sound argument in the class. To prove that the infinite class is unsound, one must show that all of the infinite subarguments are unsound. This task of showing an infinte class to be unsound can be very difficult. This difficulty is a result of the fact that no matter how many times you show justifications for the subconclusion to be unsound, someone can still find yet another justification for the subconclusion. The only way to fully resolve the infinite class to be unsound is to develop a proof that any justification will be flawed, thus making any new subarguments unworthy of consideration.