Man himself, at the very least, is music, a brave theme that makes music also of its vast accompaniment, its matrix of storms and stars. Man himself in his degree is eternally a beauty in the eternal form of things. It is very good to have been man. And so we may go forward together with laughter in our hearts, and peace, thankful for the past, and for our own courage. For we shall make after all a fair conclusion to this brief music that is man.
Last and First Men
W. Olaf Stapeldon
The life of the universe appears to place a natural physical limit on immortality, although David Deutsch in his, The Fabric of Reality, makes a compelling case for the personal experience of immortality through a virtual experience of unending time.
Some of his thoughts may have changed, with the shift in physics and cosmology currently making a big crunch less likely than an infinite cosmological expansion driven by the effects of dark matter and dark energy.
All of these questions come to play when we think about immortality.
Immortality, grounded in science rather than myth and religion, can mean a number of different things, including:
Biological immortality maintaining a unique consciousness.
Immortality of consciousness separated from biology, but yet physically constituted.
Immortality of consciousness separated from biology, but virtually constituted.
One can think of all of these in their “strong” (analogous to the use of “strong” in “strong artificial intelligence”) form:
Physically based mechanisms enabling at minimum complete or even enhanced sensory experience, which we would recognize as existence;
Consciousness with the ability to interact and understand the physical world or some virtual equivalent of it (this might include the ability to reproduce); and
Vitality, vibrant health, or peak functioning.
Accidents can happen. A sun could go super nova. Some unforeseen or unforeseeable cosmic scaled event could blink everything out of existence. Any such event could cancel any of the proposed versions of immortality.
This leads us to a slightly weaker form of immortality, just a step down from the “strong” form.
This modified strong form would simply eliminate a physical (biological or mechanical) or virtual vehicle’s inherent constraints on immortality.
Knowledge and its application have measurably lengthened average human life span in developing countries. Only the sharing of this knowledge and the wealth to apply it constrains the same increases across the entire human population.
Still, knowledge and its application have not extended the length of life reached by the furthest outliers on the longevity distribution. Humans have an empirically observed limit of roughly 125 years.
Science and medicine have made us healthier for longer. Follow these advances and they have natural conclusions on at least three paths:
Healthier life to the full current limit (125 years).
Extending the limit.
Reversing the accumulated degenerative affects of aging.
Ray Kurzweil, Aubrey de Grey, and others have thought deeply about these questions and about how science can and will likely address these problems.
Much of medicine already does much of this. Researchers and clinicians work everyday to make life better and longer. Continue what they already do and medicine must approach the current limit.
When science and medicine reach a point where they can extend average life expectancy by one year every year, humans will have an average life expectancy rapidly approaching the current limit of 125 years.
A number of technologies seek to identify the cause of the limit and to extend it. Science has already reversed the accumulated degenerative affects of aging in mice. It has made mice functionally younger by all critical measures of aging: body mass index, metabolism, appearance, even reversing gray hair/fur.
When science and medicine reach a point where they can extend the limit by one year every year, we will all have for all practical purposes achieved biological immortality.
Would so changing or enhancing our biology change our consciousness? Perhaps. What might it mean?
I don’t want to be human. I want to see gamma rays, I want to hear X-rays, and I want to smell dark matter. Do you see the absurdity of what I am? I can’t even express these things properly, because I have to - I have to conceptualize complex ideas in this stupid, limiting spoken language, but I know I want to reach out with something other than these prehensile paws, and feel the solar wind of a supernova flowing over me. I’m a machine, and I can know much more.
John Cavil, Cylon Model Number One,
Battle Star Galactica, No Exit
A few resources:
Precautionary principle http://en.wikipedia.org/wiki/Precautionary_principle
Proactionary principle http://en.wikipedia.org/wiki/Proactionary_principle