ABSTRACT

Observation and the uses of technical devices are paradigmatic methods for checking. In these cases, the method often directly indicates that the target proposition is true (or indicates that it is false). However, in many cases we want to check a proposition whose truth or falsity observation or technical devices cannot indicate directly. In these cases, inferences may be involved in the checking processes. This chapter investigates which kinds of inferences can be involved in checking methods. In the first section, it presents Nozick’s sensitivity-based account of inferential knowledge and its consequences for deduction, induction, and abduction. The reader will see that some instances of deduction can yield knowledge but some others cannot. This is in line with Nozick’s take on knowledge closure. Moreover, some instances of induction cannot yield knowledge, as critics of Nozick point out, though some others can, a rather neglected fact. Abduction can yield inferential knowledge, on Nozick’s account, if the inference is one to the best explanation. Here Nozick’s account of inferential knowledge fits well with our intuitive understanding of proper abductive inferences. In the second section, it is shown that we get the same results for checking and it is argued that this does not pose a problem for SAC. The last section investigates checking of necessary truths. Orthodox semantics of counterfactual conditionals has it that any method trivially fulfills the sensitivity and safety condition for necessary truths. Thus, one should be able to check necessary truths by using any method, which is highly implausible. It is argued that non-orthodox semantics for counterfactuals that also takes into account impossible worlds avoids this problem and provides a natural extension of SAC to necessary truths.