 Reichenbach sought to solve Hume’s problem of the justification of induction by means of a pragmatic vindication that relies heavily on the convergence properties of his rule of induction. His attempt to rule out all other asymptotic methods by an appeal to descriptive simplicity was unavailing. We found that important progress in that direction could be made by invoking normalizing conditions (consistency) and methodological simplicity (as a basis for invariance), but that they did not do the whole job. I am proposing that, in the end, Reichenbach’s own distinction between discovery and justification holds the key to the solution. (Salmon 1991: 119)