What is the nature of life? How can we define something as alive or not? Is the state of being alive dependent on the substrate of life or is it more a matter of patterns of organisation, with the actual matter of the organism irrelevant? Will we ever be able to create life? Have we already? I realise that's a lot of questions, and I have my own views on the answers to them but I'd be interested to hear other people's 'cos I'm by no means certain on all points. Personally I believe it's pointless to treat life as a finite, digital state...it should more be viewed as an analogue continuum..with very obvious not-very-alive things like rocks at one end...crystals a bit further along, viruses much further up, bacteria, and at the other end ferns, frogs, bats, badgers, pandas, people etc... With this viewpoint it also makes sense to view life as patterns of organisation rather than physical matter..the actual substrate is unimportant - life might be realised as much in the memory of a computer as in the "wet" carbon based stuff that we're most familiar with...the problem is that we have only one example of a potentially infinite variety of types of life to examine. or have we? If life consists of patterns of information, then you could argue that computer viruses are as alive as biological viruses....the internet, in it's increasing complexity, may provide the ideal environment for the next stage of evolution - artificial life... Any thoughts would be very welcome...
I think you've got it right with the continuum. If I remember correctly from Biology 101, "living" basically means having the ability to reproduce, responding to stimuli, and adapting to the environment. So yeah, in that strict definition you'd have to include software viruses. Incidently, I have another thread where this same subject indirectly came up. Someone mentioned a science fiction story where historical figures--in this case Socrates and Francisco Pizarro, the Spanish Conquistador--were simulated with software, including holograms to give them a "physical" presence. The simulations were so good that the two figures displayed consciousness and self-awareness. They then "met" each other and soon realized that something was fantastically amiss, considering that they lived 2,000 years apart. They eventually decided that they weren't "real", and in fact were simulations, even though they had no clue what a simulation was or what software is. The story asked the same question you did ... what does it mean to be "alive"? Does the fact that the software writers could shut down the simulation at any time mean that the characters weren't alive or real, in whatever sense you want to use the word? I think you'd have to say that although they weren't "alive" in the same sense that we are, by the definition above, they were.
This raises a question that I've often pondered - is something that is conscious and self-aware necessarily alive? if, for example I built this fantastic self aware, conscious computer system, that past the Turing test and every other test anyone could think of for intelligence and consciosness, it wouldn't fulfill the usually considered crucial condition of being able to reproduce...but could you pull the plug on it as it begged you not to "kill" it?? kind of off the main thrust of the thread I was getting at but an interesting question... Incindentally, I think your high school conditions are now considered quite outdated - there is in fact no universally agreed definition of life - some scientists consider viruses alive, some don't...as I've pointed out I think the whole alive/not alive thing is a red herring, but if I was forced to come up with a definition, i think mine would be : 1) Reproduces (though that causes problems in the scenario above) 2) Capable of evolving 3) Locally contravenes the second law of thermoynamics 4) Exists far from a stable state Any thoughts??
Damn, that could ruin your whole day. I don't think the question of being "alive" is a red herring, just because things such as viruses don't exactly fit the working definitions of "life". Lots of scientific laws have exceptions, but that doesn't invalidate 'em. And obviously, being alive doesn't depend on being self-aware. I think this thing of deciding that you're not "real" is damned interesting. I've read the story Caliente is talking about, and my recollection is that aspect of it was a major theme. How would you feel if you somehow discovered that you were a simulation? Or maybe a better question to ask is ... if a simulation is good enough, what the hell is the difference between that and "real" life?
I wasn't saying this but the inverse - would you have to consider something that is self aware alive? As far as the red herring issue goes, I just meant that spending time trying to decide what is alive and what isn't is a distraction from more interesting issues...besides which the life continuum idea kind of makes the distinction irrelevant anyway. As for the simulation idea... Von Neumann, Turing, Wolfram et al. have all proved that a truly universal machine could replicate the processes of any other, and that a simple cellular automata could act as a universal machine...and therefore, if you hold to a maechanistic wiew of the universe, all of reality could in fact be a massive cellular automata...and there's no reason we'd ever know..(although it has occurred to me that maybe that's why there's so much "weirdness" at the quantum level...maybe we ARE running on a massive universasal computer, and the weirdness is just 'cos we were never meant to look that closely...we're seeing beyond the bounds of our own reality...) Personally, if reality is running on a universal computer, I just hope it's not running Windows.
Why couldn't we? Isn't that just one more "fact" about our existence, like the structure of DNA or our sense of smell? If we are nothing more than software, who's to say that we couldn't be programmed to be aware of such a situation? Having said that, however, I guess the knowledge wouldn't exactly motivate you to get out of bed each morning. So maybe it's best not to know.
I didn't say we couldn't ever know, just that there's no reason that it would be obvious, or, indeed, easy to find out whether this was the case. As you said (or implicated) the discovery that reality is just a massive computer program would have serious philosophical implications, not least for most major religions, but personally I don't think it would really affect my life too much. After all, billions of people believe that all of reality was spontaneously created by the "word" of an omnipotent being...personally I find my theory slightly more believable.. I've just thought about this some more, ad maybe it would be the case that we are defined by our not knowing our true nature.....haven't thought this out fully yet, but what if the state of being human is "that which cannot know it's true nature"...I'll think some more and post again when my brain's stopped hurting....
It would be obvious if it was part of our "programming". But since it's not obvious--at least it isn't to me--then I guess that says the programmer didn't want us to know. I don't think the omnipotent being idea is inherently less believable than any other. Whatever theory you have for the beginning of the universe, you are still faced with the problem of "original cause", both for the event itself and for the physical laws and initial conditions that allow for the event. Obviously, if you accept the same logic, the omnipotent being requires an original cause as well, and therein lies the greatest mystery we know. But we're here ... we got here somehow ... evidently our logic doesn't work for original causes. Or something. This is what I meant in that other thread about brain function. It appears that, given the way our brain is wired, we always eventually come back to the requirement for an original cause. But whatever such a thing might be, the cause itself also requires a cause, ad infinitum, so that our inherent brain wiring, which works so splendidly when trying to avoid marauding leopards, fails us completely with this question. So what are we left with? A leap of faith. Where the leap takes you depends on the nature of the mystical experience you've had. What I find interesting is that all of this had been worked out millenia ago, before notions of a Big Bang or of quantum mechanics. I'm not saying that those concepts are incorrect. I'm a true believer in science, after all. But they are clearly incomplete. Why is it that primitive tribespeople in darkest wherever were able to formulate ideas of omnipotence? Or is that simply a byproduct of our brain wiring, as well? Again, we got here somehow, and we don't even question the fact of questioning how we got here.
You're assuming here that timeis, in fact linear, as we percieve it. What if time itself isn't linear, but circular, or, even more i mind twistingly, recursive? Then the whole cause-effect thing falls apart and the idea of "original cause" is no more meaningful than "final outcome"...in that case none of our myths or religions (with the possible exception of Taoism) have any real meaning. And my brain hurts......
You're assuming here that time is, in fact linear, as we percieve it. What if time itself isn't linear, but circular, or, even more mind twistingly, recursive? Then the whole cause-effect thing falls apart and the idea of "original cause" is no more meaningful than "final outcome"...in that case none of our myths or religions (with the possible exception of Taoism) have any real meaning. And my brain hurts...... No ide awhy this got posted twice....maybe it's time looping 'round on itself..
Why would it be obvious? Plenty of parts of your "programming" (e.g breathing, digesting food etc) you are completely unaware of...as you are completely unaware of the subatomic quantum reactions between tiny prticles...I don't think it would necessarily be obvious at all...this is the first thing I've actually disagreed with you on, and since I know you're too smart not to have had a good reason to say what you did, I'm keen to find out your reasoning..
What does "circular time" mean? I can't speak to that because it makes no sense to me. What I'm saying is that the universe is here. It got here somehow. Furthermore, the laws of physics are here. Where did they come from? And how is it that the initial conditions and the physical constants in the universe just happen to be tuned to the exact values necessary for the universe--and by extension life--to exist? If the values of the strength of gravity or the speed of light or the electric charge of an electron were different, then the universe would be a very different place. Perhaps it couldn't exist at all. How did those values get "chosen"? By accident? Is there a cosmic natural selection going on, so that all values were tried but only the fortuitous ones survived? The way our brains normally operate, we expect that things come from other things. This is how our everyday world is, and the mode of thought that evolved for us works beautifully in understanding it. So either this normal thought mode doesn't apply to cosmic questions, or there is some kind of original cause that we haven't been able to observe directly. "Circular time" doesn't fit anything that's ever been observed, nor does it fit with our normal mode of thought. In any case, it doesn't preclude the need for an original cause. If it's true that our normal, rational mode of thought doesn't apply to these kinds of questions, then it's an open issue as to whether it will ever be possible for us to understand their answers. Perhaps, perhaps not. I can accept the idea that "God" is simply a metaphor for the answers. It's also entirely possible that the laws of physics are a metaphor for them, as well. Or maybe that's saying the same thing. Either way, they came from something. If they didn't, then we're going to have to come up with a new way of thinking in order to describe them, in which case it may not be possible to "understand" them in the normal sense of the word. It occurs to me that this may be what the mystics have been trying to do since the beginning of time. I don't know ... I have never had a mystical experience of that nature.
We're not consciously aware of breathing and digestion, but it's not obvious that it had to be that way. You can certainly imagine a biological system where you would be aware of them. We can be "aware" of anything that our programming tells us to be aware of.
