Exploratory Factor Analysis, Instruments and the Logic of Discovery

Philosophers distinguish the logic of discovery from the logic of justification. The logic of justification usually is understood as a set of canons of inference for testing-either to confirm or refute-an explicit hypothesis. In contrast, the logic of discovery, usually is understood as a set of canons of inference for generating an hypothesis from data. From early in this century until recently it was common for philosophers to deny the possibility of a logic of discovery; there could be psychologically useful aids to promote discoveries, but these methods, and the hypotheses they generated could not be understood as privileged in any way. According to Larry Laudan, prior to the turn of the century, the circumstances through which an hypothesis was discovered provided the primary reason for its acceptance. The logic of discovery was a logic of epistemic warrant. Laudan worries that the recently revived interest in the logic of discovery cannot serve this same purpose: