Final answer:
Deontological ethics is the theory that bases the morality of actions on duty or rules, ignoring the consequences, and is exemplified by Immanuel Kant's categorical imperative.
Step-by-step explanation:
The ethical theory based on the idea that actions must be grounded in moral rules or duties, regardless of the consequences, is known as deontological ethics. In this framework, it is the adherence to duty or rule that determines the morality of an action, not the outcome of the action. This is in contrast to teleological or consequentialist theories, which evaluate actions based on the results they produce. Immanuel Kant, a prominent figure in modern philosophy, developed the concept of the categorical imperative as a foundational principle of deontological ethics, which dictates that an action is morally right if it can be universally applied as a norm of rational conduct.