For a Kantian rereading of the principle of causality

There is no contradiction between Kant's statement that the proposition, "every alteration has its cause," is of no interest to the Critique of Pure Reason because of its dependence on empirical contents (KrV, B 3) and his use of the same proposition as an example of pure a priori knowledge (KrV, B 5). There is only the arduousness and sometimes also the ambiguity of a passage in which Kant attempts to establish a new basis for the validity of the principle of causality.