system
Given the following post, respond as if you're commenting on Reddit:
human
Why is incest immoral?

Why is incest considered immoral? I know it feels immoral but I can't find any logical reason why it is.

I know that it may produce offspring with serious health problems but I mostly want to talk about non biological reasons. What if the incestuous people use protection or if they are of the same sex or one of them is infertile. Is there a reason then why they shouldn't have sexual relationships? Does it make a difference if it's with a parent/sibling/cousin? Why?

Also if the only reasons are biological do you think incest should remain illegal? Does it differ from cases such as when it's highly likely your kids will have anemia? (In which case if I'm correct you can still legally have children)
gpt
I don't think many philosophers think incest per se is immoral. Any reasons to think "incest" is immoral turn out to be reasons to think something else is immoral, like sex in the context of relationships where the power dynamics are such that one person is massively subordinated to the other, or reproduction that makes the resulting kid very badly off.