Abstract

There are three riddles of induction. The New Riddle is this: How do we give a definition of 'projectible hypothesis' which is noncircular, and which yet divides all universal hypotheses unerringly into two disjoint classes--the projectible and the unprojectible? This is a purely analytical problem: build a machine which sorts hypotheses in the intuitively correct way, it making no difference why the machine works, so long as it works : Why should we rely on inductions to acquire beliefs about the unobserved, rather than on any other method of inference to acquire alternative beliefs about the unobserved? ;Here, we solve all three riddles. Chapter One is devoted to the New Riddle. Chapter Two serves to introduce some important matters concerning counterfactuals and causation, necessary for the hard labor of Chapter Three, which addresses the Old Riddle. The true pattern of inference from experience is discussed and two kinds of counterfactuals are distinguished, suggesting an answer to Hume