For example, “If you intend to go to law school, take the LSAT” would be a hypothetical imperative since it commands an action (taking the LSAT) as a means to some end (going to law school). If you didn’t have any ends that would be served by taking the LSAT, the command for you to do so would be withdrawn.  Categorical imperatives, such as “If someone is drowning nearby, offer assistance,” differ in two ways.  First, the command to offer assistance applies to you regardless of whether offering assistance serves any of your (desired or intended) ends.  Second, you have a reason to offer assistance regardless of whether doing so serves any of your (desired or intended) ends.  (Philippa Foot has argued that this second feature doesn’t follow from the first: a rule of etiquette, or a club rule, may apply to you regardless of whether compliance with it serves any of your ends, but you may nonetheless have no reason to comply with it. See Foot 1972.) 