Why is Adorno interested in Kant? in the text, Problems of Moral Philosophy?
as a related question Why does Adorno prefer to use the term “morality” rather than “ethics”
Why is Adorno interested in Kant? in the text, Problems of Moral Philosophy?
as a related question Why does Adorno prefer to use the term “morality” rather than “ethics”
First the related question, then Kant.
Morality and ethics
Adorno's basic idea is that 'morality' is associated with the view that there is a harmony between the life of the community and that of the individual. The customs and traditions of the community provide the substance of morality, and it is by following them - adhering to them - that the individual does what is right. Acting rightly involves a precise interlock between customs and traditions and the conduct or behaviour of the individual.
This seems to Adorno an indefensible position, not least given the serious evil of so many communities and their customs & traditions, and the flagrant injustices that they embody and exhibit.
Also Adorno observes a strong connexion between morality and repressive sexual rules and practices. If morality is inadequate to our authentic sexual natures by its endless sexual prohibitions, then it imposes unjustifiable constraints.
In contrast ethics 'contains the idea that people should live in accordance with their own nature' (13) and not in line with constraints 'forcibly imposed from outside' (13 again) of precisely the sort that morality embodies.
This is a very brief summary but I think it does show why Adorno wants to distinguish morality from ethics, and why he gives the preference to 'ethics' over 'morality'.
Adorno and Kant
There is a link between the idea that 'people should live in accordance with their own nature' and Kantian autonomy and self-legislation. Kant thinks ethically in terms of a life in which the agent gave her- or himself a law of conduct. While Adorno does not finding appealing or plausible Kant's assumption and requirement that this law would be identical with the law every other rational creature gives itself, he does recognise an affinity between Kantian autonomy and liberation from the the constraints of morality 'forcibly imposed from outside'.
References
Theodor W. Adorno, Problems of Moral Philosophy, ISBN 10: 0745628656 / ISBN 13: 9780745628653 Published by Polity 2001-09-14, Oxford, 2001.
Raymond Geuss, 'Adorno's Gaps', Arion: A Journal of Humanities and the Classics, Third Series, Vol. 12, No. 2 (Fall, 2004), pp. 161-180.
I. Kant, Groundwork of the Metaphysics of Morals (Cambridge Texts in the History of Philosophy), ISBN 10: 0521626951 / ISBN 13: 9780521626958 Published by Cambridge University Press, 1998.