The critique commonly known as the Critique of Pure Reason essentially aimed to secure the safe, but exclusive ownership of reason - which has its own domain, particularly in cognitive ability, as it contains a priori principles of knowledge - against all other claimants. Similarly, in the Critique of Practical Reason, the ownership of Reason was indicated, which does not contain a priori principles but only in relation to the desirable.

If, therefore, the critical ability, which is an intermediate term between understanding and Reason in the order of our cognitive abilities, also possesses a priori principles considered in themselves? whether these are constitutive or merely regulatory (and therefore do not declare their own domain)? whether this ability a priori provides a rule for the feeling of pleasure and displeasure, as an intermediate term between cognitive ability and the desirable (just as understanding imposes a priori laws on the former, and Reason on the latter): all these are questions that will be addressed in this Critique of the critique's ability.

Immanuel Kant