"But people consent(sic) to harmful things all the time..."
I take it you are considering where there is a consensual relationship, that is both partners are "equal" and one is not dominating or taking advantage of another. One could include in here doing drugs together, S&M, extreme sporting, and so on.
Ski-doo event starts Killer Avalanche
Indeed, so whether an action is harmful becomes relevant to consent.
Young adults who are dependent and living at home, not in a position to offer a consensual relationship...."According to whom?"
According to me. I am offering a morality based on "do no harm", and not to those in a vulnerable and dependent position. Young adults who are dependent and living at home are in such a position. I specifically mentioned this because an arbitrary age limit doesn't work. Is a young adult a consenting adult at 12, 16, 18, or 21? Children as young as twelve make decisions regarding their health and who they want to live with (i.e. custody battles). Instead of picking an age, let's say a person living independently has reached the age of consent. That may be at 28.
You don't get to decide that you have a say on who has consent simplybecause you WANT it to be so.
Neither do I.
That is an issue for the law to decide and soemthing like that tends to be cultural and societal.
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.only if the impulse is harmful right?
That's right. Impulse control is still needed and required. Not that we are telling people which impulses they should act on and which they should ignore, only that some are off the table.
We get back to who decides what is harmful and IF that matters and who decides concent and in the end, what we are getting is:
Whatever is acceptable at the time.
It isn't a question of leagl even because, in some places people concent to illegal sexual activity "all the time".
IT seems that it isn't about what is legal or about what is harmful really, it is about what we ( society) decides at any given time, to be "OK".