<ethics, stoicism, metaphysics, categorical imperative> <hypothetical imperative, political philosophy, psychology> what an individual is obliged to, or ought to do. If an individual has a duty to do X it is not permissible for them not to do X; and if they have a duty not to do X then it is not permissible for them to do it. Kant believed the commands of morality, being categorical, create perfect duties allowing no exceptions. Nonmoral imperatives, on the other hand, being hypothetical, create imperfect duties which allow of exceptions. See categorical imperative, hypothetical imperative.
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