Dayum, this is a deep thread of conversation. I think I'm getting a headache from thinking too hard. I'mma go pop some painkillers and watch a season of Jersey Shore, I need to stop thinking for a while.
In all seriousness now, debating just what the value of a life is is a really vast thing. There's so many variables and different interpretations of such a topic.
Personally, I feel there's several main factors to determine the value of a human mind/life.
1) Does the individual in question value their life? This is probably the biggest factor.
2) Do others value the individual's life?
3) Does the individual actively pursue interests and achievements, however you might define such, in any shape or form?
4) Does the individual and their peers also value these achievements?
Sure, this is vague, but the topic itself is incredibly vague and hard to define.
As to the suicide topic I brought up, I don't understand how "forcing the suicidal to not want to kill themselves" could help. Making such "help" "mandatory" would in all likelihood only generate resentment towards the help simply because the help is "forced" on them and not provided out of appreciation for their life.
As for actually committing suicide, generally the individual would have at least been thinking of the action for a while. Sure, there are cases where people just kill themselves in the heat of the moment, but there's hardly much help that could've been found for those cases.
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Also, the ultimate reason we question the morality of killing is because we have no idea what happens when we die. No one knows for sure until they themselves die. Even if someone came back as a ghost, and tried to spread the word to the world about what death really was, there would always be some doubt, disbelief, and the fear of the unknown that would be death.
If we knew for a scientific fact that when one dies their mind travels to another dimension and becomes a free floating form of sentient gas and was free to ponder all the mysteries of the universe for eternity and ultimately transcend humanity, would we be so afraid of death? Would we still hold killers to be detestable monsters?