 Causal explanation, probability, and the Bayesian method are the key ingredients of Salmon’s view of rationality, which is strictly entrenched with his version of realism. A further ingredient is the notion of propensity taken as causal tendency (see  § 2.3).  Salmon’s “Rationality and Objectivity in Science” (1990d [2005]) defines three grades of rationality standing in different relationships with objectivity. The first kind of rationality has no connection with objectivity and is identified with the coherence of degrees of conviction, a key requirement of the Bayesian method. This is called static rationality. Bayesian conditionalization, offering a tool to update one’s degree of conviction, shapes a stronger type of rationality called kinematic. The highest grade of rationality is called dynamic, and involves a closer connection with objectivity.