I have never understood this distinction between mental health and physical health. Especially when it comes to euthanasia debates and who gets denied and why.
To me it is the same things as it has the exact same end result.
Chronic Physical Illness: Terminal or otherwise, that compromises acceptable quality of life. Avenues of recovery and respite having been exhausted. End result, loss of value in living.
Chronic Mental Disorder: Which compromises acceptable quality of life. Avenues of recovery and respite having been exhausted. End result, loss of value in living.
Both are costly and both produce burdens on the surrounding people and the taxpayer. So I still see no distinction.
If people in either of these states reach that conclusion, have not been coerced, demonstrate capacity and an ability to consent. It should not matter if it is mental health or physical issues at that point. That seems humane to me. It is the the only way you can respect autonomy of a person. Sad, but better than the alternative of living life that has no value to you any more.
People will make the counterpoint, that the mentally ill are incapable of knowing what they want because they are mentally ill. But that does not hold water either. Because that is also true of physical issues that affect mood, impulse control and produce their own deluded states.
It is why capacity law is meant to exist in the first place. It should cover this.
Also physical health issues feed into mental health issues and vice versa. All exacerbating the other. Having a mental health condition does not suddenly render the physical condition non existent either. If anything it will worsen the natural psychological pressures a non labeled person still has to contend with.
It should go right back to capacity and consent. This distinction between physical and mental seems mostly a political one or a knee jerk reactionary one founded on some abstract morality. Or flawed understanding that assumes incorrectly that people with mental health diagnosis cannot make decisions. If they can be prosecuted for a crime and found culpable while having a mental health diagnosis that is kind of proof of the opposite. There is a lot of that proof locked up in prisons.
It is fair to point out a physical diagnosis may produce objective certainty that you will not recover. The same can't be said for the mentally disordered. But that isn't entirely true either. Because some are declared treatment-resistant and have exhausted what is on offer. To the point services quite literally tell them to focus on quality of life concerns.
If you cannot have quality of life then euthanasia seems fair and respectful of autonomy.
This one of my personal favorite topics. I think the fundamental question is whether there is a "mind and body" or just a "body". The brain is an organ, and like any other organ can fail or suffer trauma. Philosophy and subsequently the sciences are rooted in this unfound, mythological, religous-like assertion that the mind, more specifically, the ego, operates under this supernatural realm that cannot be understood by contemporary means of obversation.
This subject reminds me both of how young modern science is, and how much it has to this day been influenced by political (meaning economic) forces. Most scientist were/are openly religious people, it wouldn't be surprising that cognitive dissonance compels academia to reject the evidence that contradicts against fundamental assumptions that are pillars to society.
The most significant scientific development occurs in ages and areas with high amounts of capital accumulation and concentration of capital. To put it succinctly, scientific development is greatest within warring empires. However, the focus during this time is not for some romantic puruit of truth, intellectual curiosity, or societal crisis (well sometimes) the primary concious effort is for developing, manufacturing, and enhancing technology that kills large numbers of people quickly. That describes all major scientific developments, up until the mid-late 20th century. That goal had been achieved.
By the 1960's, for the first time in human history, possibly world history, a single species had the ability to trigger it's own extinction (more accurately a mass extinction) at a single impulse, to quote J. Robert Oppenheimer in July 16, 1945 referencing text from Hindu scripture "Now I [have] become death, destroyer of worlds". And from sheer luck, that impulse has yet to be triggered.
However, immediately after achieving the goal of absolute destruction, a plight that modern science had undergone for some 200+ years. There was a realization, more like an acceptance that this technology could not ever be controlled, concealed, or used like some scientist had warned nearly 4 decades earlier. Instant communication, GPS tracking, ICBM, nuclear warheads, etc. was too spontaneous, too devastating, too absolute to wield. Nuclear warheads marked the first time the upper echelons of power feared technology, a fear that our collective feat, offspring if you will, could be used against us.
So a new goal was created, since we have achieved absolute collective destruction, we must now develop the means for a selective absolute devastation. After all, the biggest problem with nuclear warheads is it leaves the lands baron snd desolate, no way to accumulate capital from the area selected for potentially thousands of years. We must create a technology that can unequivically annihilate the "other", while leaving the land intact (enough) for the extraction of capital.
Intense debates were had over what form this selective devastation should manifest, but not only must only terminate the target, it must be so capital intensive only the richest most absolute empire have the resources to wield this technology against the world. It wouldn't matter if the blueprints were exposed to the "other" because the market's contriction will render it useless to those without the global manufacturing network. Eventually, the first manifestation was born, and soon introduced in the late 2000's- early 10's, the US drone program, likely the greatest act of state terrorism in terms of civilian deaths in human history.
Yet, with all these resources, all these decades, all these research organizations, all the highly educated talented people, etc. No one ever bothered to question why we as a collective whole are so hell-bent on finding new ways of killing ourselves? Is death is our sole purpose? is technology the only medium scientific theory can use to interact with the world? Is global mass manufacturing, and subsequently anthropogenic environmental alteration is necessary?
If there is a "mind and body" that interacts symbiotically together as seperate entities, does that mean given the habitual warmongering practised by communities of people and civilization, that by nature we as a species seek death? Or is death the natural consequence of our actions, whether we as "individuals" (a concept with no universal scientific definition) intended for that result or not? If so, then what significance does having free-will hold if we do not possess the cognitive capacity for at least, limited omnipotence? There would still be unforeseen outcomes and unknown mechanisms to our behavior that prevent us from effectively utilizing such potential.
Ultimately, the debate of "free-will", "mind body" is pointless, because reality acts regardless of our perception. The only thing that would change is the form of our society as certain practices would no longer be justifiable such as retribution or shame. The concept of "free-will" is a psychological and social inhibitor of freedom, redemption, forgiveness, empathy, learning, and creativity. It's a draconian-era invisible shackle to the human spirit ironically sold to us as liberation and truth.