It's Darwinistic, but in this society, we don't leave deformed babies on the hillside to expire. I have mixed feelings about that topic in general at this point. In fact, the trend in healthcare ethics (something you may be interested in) has been, I have heard, to move toward a reformation of attitudes toward death in general and accepting different standards for what constitutes existence (my field of interest.) I heard someone on NPR a while back that was saying that, with health care costs and the likely outcome of terminal diseases, that heroic measures neither benefit the individual or society at large and maybe they should be allowed to accept an earlier death. I'm not sure. I know my mother has an aortic aneurysm that she simply decided not to do anything about and it will certainly kill her, suddenly. So, I don't know. It's a fiery topic for discussion in the abstract and it's very real, too. If someone is chemically addicted and can't be helped by reasonable measures, should they be allowed to simply die? Most drugs make a permanent change in the brain making addiction permanent in essence, same for alcohol, which is not a drug but a toxin, like gasoline or glue.
So, glad I could be all cheery and shit, but that's why I have this here big brain. And you know what they say about guys with big brains - no need to overcompensate.