ABSTRACT
David Hume’s examines the idea of cause by searching for the impression or impressions from which it is derived. The justification of the contention is really a challenge; show a factual inference from an observed to an unobserved object founded on a relation which is not either itself a causal relation. The question of the nature of factual inference is therefore how and under what conditions is the vivacity extended from an impression or memory to an idea, so that the idea becomes a belief, a conclusion of inference. The causal relation is a relation of necessary connexion, as Hume says, and chance is the opposite of necessity. He wants to distinguish belief from similar but different states of mind; and, since he has maintained that the causal relation is the sole foundation of all factual reasoning, he wants to distinguish rational beliefs from irrational beliefs.
