Wanna bet??For an individual to determine whether their life has quality or not is one thing; trying to decide that for another human being is much, much more difficult.
Scenario: You have been married for 40 years. Your wife has been your best friend and companion since you were both teens. Sadly, she has suffered a catastrophic illness, and is clinging to life on a respirator. You had many conversations with her about this kind of thing, and over the years, she consistently told you that she would rather be let go, than linger in a state like that. But the illness struck suddenly, before she had the chance to put anything legal in place, to deal with an issue like this.
The doctor walks up to you, and asks, "There is nothing we can do for her. The only thing keeping her alive is the respirator. What do you want us to do?"
Would you be morally and ethically wrong to say, "She doesn't want this, turn off the machine"?
Would you be morally and ethically wrong to say, "I don't care what she wanted. Keep her alive, at all costs"?
You have now entered the paradox zone. You can't win, either way. So, what do you do?
Those who claim this issue is straightforward or simple, haven't really gone through an exercise like this.
I'll let you know later.