A. The Imperial Category | B. The Categorical Imperative | ||
C. The Hypothetical Imperative |
D. The Empirical Imperative | ||
(B) The categorical imperative receives several 'formulations' by Kant, though it is possible to questions whether they really are just different ways of putting the same thing. One formulation is: 'Act only on that maxim you can will to be a universal law.'
(C). When your reason tells you to do x if you want to achieve y it is issuing what Kant calls a hypothetical imperative.
(A) and (D) are not Kantian terms.