http://www.bbc.com/future/story/20140704-i-bring-the-dead-back-to-life
Cryonics and cryogenics has been a well-trodden trope in popular fiction for decades, from the works of Robert Heinlein and Arthur C. Clarke (of the "Golden Age of Science Fiction") to Captain America's decades of being frozen in a block of ice. Science is nowhere near such capabilities, of course, and it's important for the general public to understand what is and is not possible, to be able to distinguish between fact and fiction (and fiction that might well become fact in the future). Most of the scientists cited in the above BBC article, for example, are careful to qualify their work. But the mere possibility -- the mere notion that we might be capable of blurring the boundary between life and death -- calls into question some of humanity's most deep-seated beliefs.
One of the most memorable moments in genomics research (which could be considered the other end of the debate) came from Dr. Craig Venter, the geneticist and entrepreneur best known for his work in mapping the human genome and in artificially synthesizing life. When he was asked how he felt about "playing God," Venter famously replied, "I don't play."
Clever quip aside, the creation of life and the reversal of death are traditionally the provinces of myth. Much of human fascination with divinity and the supernatural stems from our desire to understand -- and in some small way, influence -- these opaque, immutable bookends to our time on earth. We, like all other living creatures, are by nature afraid of death, and seek to stave it off as long as we can. If given the option to return from the other side, I'd venture that most people would do so without hesitation. And who wouldn't want to bring back a newly-deceased loved one, if they could?
What, then, might it mean to live, if we could choose not to die? Issues of reproduction and overpopulation aside (though those, too, would become important challenges), would near-immortality change the nature of humanity? How and why would one decide to die? Tolkien's elves, incidentally, would be a close approximation of that dilemma.
I'm reminded of something a wise man once said, about that final journey:
"After all, to the well-organized mind, death is but the next great adventure."
~Albus Dumbledore, Harry Potter and the Sorcerer's Stone