  Newton's first two rules of reasoning appeared in the first edition (there labeled as  hypotheses[41]), the third rule was added in the second edition, and the fourth rule, in the third edition. These are rules intended to govern evidential reasoning in natural philosophy, akin to rules of deductive reasoning except for their very much not guaranteeing true conclusions from true premises. In particular, Rule 2 authorizes the inference from same effect to same cause, a notoriously invalid inference, and Rule 3 authorizes inductive generalization to all bodies universally of those qualities of bodies “that belong to all bodies on which experiments can be made.” Newton's phrasing carries no suggestion that these rules yield truths or even a high probability of truth. The operative phrase in both Rules 3 and 4, for example, is properly translated “should be taken,” and Rule 4 makes the provisional character of the authorized inferences explicit: