Immanuel Kant · Philosophy
Kant’s supreme principle of morality - that we must act only on principles we could will to be universal laws, and treat humanity always as an end, never merely as a means.
Kant sought the supreme principle of morality - the fundamental principle from which all our moral duties derive, grounded not in consequences, desires, or feelings, but in reason alone. Morality, Kant argued, is not based on consequences (producing good outcomes), nor on desires or feelings (what we want or feel), but on reason and duty - on acting according to rational principles that hold for all rational beings, regardless of consequences or desires. And the supreme principle of morality is what Kant called the Categorical Imperative - a command of reason that holds categorically (unconditionally, for all rational beings, regardless of their desires or goals), as opposed to a merely hypothetical imperative (which holds conditionally, depending on one’s desires or goals: ‘if you want X, do Y’). The Categorical Imperative is the unconditional command of reason - the supreme principle of morality, binding on all rational beings as such - from which our moral duties derive.
Kant’s second great formulation of the Categorical Imperative is the ‘Formula of Humanity’: ‘act so that you treat humanity, whether in your own person or in that of another, always at the same time as an end and never merely as a means.’ This requires that we treat persons (rational beings) always as ends in themselves - as beings with their own intrinsic worth and dignity, their own rational ends and autonomy, to be respected - and never merely as means - never merely as tools or instruments to be used for our purposes, without regard for their own worth, ends, and autonomy. We may use people as means in a sense (we rely on others - the shopkeeper, the worker - for our purposes), but never merely as means - never merely as tools to be used and disregarded, without respecting their own worth, rationality, ends, and autonomy as persons. To treat someone merely as a means - to use, manipulate, deceive, or coerce them merely as a tool for our purposes, without respecting their own worth and autonomy - is to violate their dignity as persons and to act wrongly. This formula - treat humanity always as an end, never merely as a means - grounds morality in the respect for persons as ends in themselves, with intrinsic worth and dignity, and is one of the most influential moral principles ever formulated.
At the foundation of Kant’s ethics is the good will - the will that acts from duty, from respect for the moral law, which Kant held to be the only thing good without qualification. ‘Nothing in the world can possibly be conceived which could be called good without qualification except a good will.’ Other things (intelligence, wealth, even happiness) can be used for good or ill, and so are not good without qualification; but a good will - a will that acts from duty, from respect for the moral law - is good in itself, unconditionally, regardless of what it accomplishes. The moral worth of an action, for Kant, lies not in its consequences but in the motive from which it is done - specifically, in being done from duty (from respect for the moral law), rather than from inclination, self-interest, or desire. An action has moral worth when it is done from duty - from respect for the moral law, because it is right - rather than from inclination or self-interest. The good will, acting from duty and respect for the moral law, is the foundation of Kant’s ethics and the only thing good without qualification - grounding morality in the good will and the motive of duty, rather than in consequences, inclinations, or desires.
This is the opening of the lesson. The rest — the dialogue, the primary source, and the recall — is in the app.
You learned that Kant’s Categorical Imperative requires acting only on universalisable maxims and treating humanity always as an end. Explain the Categorical Imperative and its formulations in your own words.
Leads to John Rawls.
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