What is consciousness?

A conversation topic came up at dinner with geeky science colleagues about a future of uploading human consciousness to a computer or a robot body as a way of living forever. I guess non-yogis and non-dancers -- basically people who are not intimately in touch with their limbs -- still think of their bodies as a vessel that serves to transport the brain from place to place. They think of the organic flesh and blood as a burden and would happily replace them with robotic body parts instead, thinking they will serve as enhancements, allowing them to move faster and better (I am not sure if athletes are willing to take enhanced robotic limbs if it'll improve their performance. I suspect some might).

So, what exactly is consciousness? Can it be separated from the neurons and get "uploaded" into a machine? Before I started yoga I did a variety of sports and exercises for the purpose of health, ie. if I don't exercise regularly then fat will accumulate in my blood vessels; my body will get stiffer and I'll easily injure myself doing simple every-day life activities (eg. carrying grocery, catching a bus, trying to reach something from a high shelf, etc). I guess if physical health is the only reason that we exercise, then replacing our aging flesh and bones with robust machine parts can indeed be a viable option.

But wait a minute, even assuming consciousness can be separated from the body, would my consciousness want to live in a machine? We've evolved to derive pleasure from eating and the human touch. I suppose one can implement artificial tongue and skin (and even the equivalent of sexual sensory organs if you will) on the robot so that pleasure can be maintained, but would life still be the same? Now, as yogis, we have learned to savor the sensations from the inner parts of our body as well: the expansion and of the lungs as we inhale; breath leaving the nostril as we exhale; we have learned to use rhythmic breathing to calm our anxiety and the busyness of our thoughts. Transporting our consciousness to a machine solves the problem of aging bodies, but how does it deal with our messy consciousness and subconsciousness?

I suppose if we can pull consciousness out of the brain, it should also possible to sort out our thoughts before we upload it to a machine. But what would a sorted mind look like conceptually? Would it be like a file cabinet where each thought has been given a label and sorted alphabetically (and by color, by size, plus some other classification scheme)?  Are emotions part of our consciousness? If we remove all of our emotions and feelings would we think more clearly? Would that still be considered as living?

Maybe I've gotten less imaginative, or maybe I'm too caught up on the details, but I can't imagine a good life living inside a machine. I guess if I became quadriplegic then I wouldn't mind getting replacement limbs that my brain can control again. However I'm not sure what total body replacement will "feel" like (am I too attached to my central nervous system and my breath now that I've become a yogi?). The technology of an artificial heart is already available, which means that some people are currently walking around with a machine controlling their blood flow, ie. they live without heart beats. That's such a strange concept to me!

I think people who think that uploading their consciousness to a robot, or even the internet is an appealing idea to extend life may not be intimately in touch with their bodies (which tend to be true for intellectuals and those who are happy with desk jobs as a career). But then again, I am not 80 years old with a broken hip. However, by the time one reaches 80, it's not just the body that deteriorates; the mind deteriorates too, as a result of agin neurons. So, if we want to transfer our consciousness to a medium that's more superior than our organic flesh, is it best to do it when we're in our 20s? But that's when our bodies are at their prime. So... this would be an option only for the handicapped and people who hate exercising and doing sports? Too many streams of thoughts going on in my mind right now.

What are your thoughts on the concept of consciousness? If you can somehow pull it out of your brain and transfer it somewhere else (or into someone else), would you do it?