To see this, suppose Sid is a cognitive psychologist running experiments in which subjects hear word pairs and an hour later are given the first word of each pair as a cue and are asked to remember the second word.  Sid collects his data with the utmost care, and holds to the highest standards of data collection and interpretation. Suppose Sid does many such studies and concludes that his studies show that in conditions C, memory for words that have been paired with words that are used as cues is generally reliable.  Finally, suppose that given his general assumptions, Sid is right in claiming that his research indicates general reliability.  Still, in conducting his research as he does, Sid depends on the general reliability of his own memory at many turns.  For example, in setting up the experiment, Sid draws on his memory of the principles for conducting his research; in cuing the subjects and collecting the data of their responses, he depends on his memory for believing that this group of people is the same group of people to whom the lists were originally read; collecting the data from the each person, Sid remembers not just that this person is in the group, but also which person in the group this is, so that the data can be accurately recorded; finally, in drawing out the conclusions from his research, Sid must, at the very least, keep in mind the procedures of the study, the summaries of the empirical data, and the principles guiding inductive inferences.  