The orthodox Neyman–Pearson theory of hypothesis testing considers how to decide whether to "accept" or "reject" a hypothesis, rather than what probability to assign to the hypothesis. From this point of view, the hypothesis that "All ravens are black" is not accepted "gradually", as its probability increases towards one when more and more observations are made, but is accepted in a single action as the result of evaluating the data that has already been collected. As Neyman and Pearson put it: