 Note: B(3) is a “second order” thesis about the dialectics of the reductio; the antecedent is a condition where the externalist grants that the *premises are warranted (regardless of whether they are warranted). Thus B(3) says that the externalist will be presuming (3), if she concedes warrant to the *premises in the first place. It is in this sense that (3) is presupposed once the deduction is mobilized, resulting in transmission failure.