I have to admit that I'm often surprised by those who say they do not want to live longer. I see simple statements and lots of knee jerk reactions and fear. However, I rarely see logic to back up these comments.
Usually people say it is unnatural and they don't want to live longer than normal. By that logic then they shouldn't be vaccinated against disease and mankind should never have "encouraged" health practitioners throughout the ages to avoid the plague, cholera, tuberculosis and other ravages. The thing is, there aren't a lot of people who in retrospect think the discovery of anti-biotics or the small pox vaccine wasn't worthwhile. So, I think most people do want to live longer but with a high quality of life and with their friends and family also living longer. It is likely fear (or pain, or major depression) that stops these people from wanting to live longer.
Instead I believe that if any of the greatest minds of the past century had lived 20, 30, maybe 50 years longer that the world would be a considerably different and better place. Prolific inventors, thinkers, artists, and humanitarians who could live longer may have helped us enter a new age. An age where ones life work is not cut short but can be developed meaningfully and perhaps much more fruitfully.
If Einstein had lived an extra 30 years would we be traveling to other dimensions or to distant galaxies from the folding of space and time? If Mother Theresa had an extra 50 years would the world be a better place?
I've heard an argument that it is selfishness and vanity that cause people to want to live longer. While I am unsure about the vanity argument as martyrs can also be considered vain I do believe that the reasons for living longer can be selfish. However, they can also be selfless.
In my limited experience as many people age they become less selfish, contribute more to their communities, nurture the personal and spiritual growth and health of others more. It is certainly comforting to know that by extending life by 50 years that these traits may blossom as a new stage in human development. Perhaps with more selfless service to others and our communities the light in all of us shines a little brighter.
I know of people who have passed away that wished they had more time and I also know people who were ready to go. Ultimately though, I believe the majority of us want to live longer.