Era: Enlightenment (late 18th c.) Key figures: Immanuel Kant
Morality is a demand of reason, not desire: act only on principles you could will everyone to follow, and treat every rational being as an end, never merely a means. Dignity, not outcomes, is the measure.
Signature commitments
The categorical imperative: act only on a maxim you could will to be a universal law.
The humanity formula: treat persons never merely as means, but always also as ends in themselves.
A good will is good not for what it achieves but in itself; moral worth lies in acting from duty, not inclination.
Where it stands on the axes
The nature of realitycontested
Idealist. Transcendental idealism: the mind supplies the form of experience; things-in-themselves stay unknown. Empirically realist about the world we experience.
How we knowcontested
Rationalist. Synthetic a priori knowledge; but 'thoughts without content are empty, intuitions without concepts are blind' — a synthesis of both wings.
What makes an action right
Duty-based. The paradigm of duty-based ethics.
Where meaning comes from
Discovered. Reason reveals the moral law within and the dignity that comes with rational autonomy.
What people are like underneathcontested
Constrained. 'Out of the crooked timber of humanity no straight thing was ever made' — yet we carry a fixed capacity for autonomy.
Free will
Libertarian (free will). Transcendental freedom: the will is genuinely self-governing (autonomous), located in the noumenal self.
The individual and the group
Individualist. The 'kingdom of ends': each rational being is an end in itself with inviolable dignity.
How power should be arranged
Egalitarian. Equal moral worth for all rational agents — though his political writing is cautious about who exercises power.
How change should happen
Reform. Favoured gradual republican reform and 'perpetual peace'; regarded violent revolution as illegitimate.
Marked readings are ones serious scholars dispute; the note says how. Traditions are living arguments, not fixed doctrines.
Common misreadings
That Kant ignores consequences entirely — he cares about ends, but denies that good consequences can make a wrong act (like a lie) right.
That the categorical imperative is just the Golden Rule — Kant explicitly distinguished them; his test is about universalising a maxim, not about what you'd like done to you.
Where a reader might diverge
If you'd tell a lie to save an innocent life, you diverge from Kant's most notorious hard line against lying.
If you think morality ultimately answers to human happiness or flourishing, you've left duty-based ethics for consequentialism or virtue ethics.
A challenge to it
Benjamin Constant / the consequentialist: The 'murderer at the door' case: if a killer asks where your friend is hiding, Kant's ban on lying seems to make honesty an accomplice to murder — a sign the rule has been cut loose from the good it was meant to serve.
In their own words
Act only on that maxim whereby thou canst at the same time will that it should become a universal law.
— Immanuel Kant, Groundwork of the Metaphysics of Morals, Akademie 4:421Thomas Kingsmill Abbott translation (Formula of Universal Law); Abbott's archaic 'thou canst' is preserved rather than modernised.
Two things fill the mind with ever new and increasing admiration and awe, the oftener and the more steadily we reflect on them: the starry heavens above me and the moral law within me.
— Immanuel Kant, Critique of Practical Reason, Conclusion, Akademie 5:161Thomas Kingsmill Abbott translation.
Inner Axis never pins a school on you. A reading describes where your answers resemble a tradition and where they part from it — a family resemblance, not a label you carry.