system
Given the following post, respond as if you're commenting on Reddit:
human
What would Immanuel Kant say about homosexual sex?

Kant denounced masturbation and non-procreative sex as immoral. Would homosexual sex, which has no potential for procreation whatsoever, be similarly denounced by Kant?
gpt
Refer to the *Metaphysics of Morals* (not the Groundwork!):

"Sexual union is the reciprocal use one human makes of the sexual organs and capacities of another. This is either a natural use...or an unnatural use, and unnatural use takes place either with a person of the same sex or with an animal of a nonhuman species. Since such transgressions of principle...do wrong to humanity in our own person, there are no limitations or exceptions whatsoever that can save them from being repudiated completely" (p.96 ; tr. Mary Gregor [the Cambridge Texts in German Philosophy edition])

So he's pretty clearly unilaterally against it. Metaphysics of Morals is actually a pretty helpful and unduly ignored text because Kant lays out basically all of his specific ethical beliefs in it (showing us just how inhumane his ethical theories are, according to many later commentators)