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Life only physical/chemical reaction?

  1. Jan 24, 2006 #1

    A few days ago a interesting thought stroke me during my chemistry lesson.

    I don't know how I started thinking about it, but i just thought that prokaryotes may not really be living organisms, but rather just a system of elements and molecules and a many many chemical/physical reactions. One can't really say prokaryotes are intelligent and they are the simplest cells known. Maybe all their actions are just triggered by the quest for the lowest energy level (what initiates all reactions, i.e. molecular boundings, quantum jumps of orbiting electrons to a lower energy level if one is free, etc). (Although they are still extremely complicated when described completely on a molecular or atomic level)
    As I thought further and furhter, I know can't see any differences between an organic and living organism and a large quantity of chemical/physical reactions (neglecting complexity now, no doubt that organisms are by far more complicated)

    What do you think about it?
  2. jcsd
  3. Jan 24, 2006 #2


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    I personally think you are right. Every time the scientists have a breakthrough in understanding living things, it supports the thesis that they are causal mechanisms. Nothing that has ever been discovered contradicts that view.

    Of course many people on this forum have a different view of things.
  4. Jan 24, 2006 #3
    not being able to distinguish a real difference is a invaluable.
    i think you might want to think about "intelligence". intelligence, for humans, is complex. is there something more simple that translates to simpler organisms and entities? perhaps awareness?

    awareness does seem to be the foundation of our complex intelligence. is it possible that the most simple forms are, in reality, acting and reacting on the basis of the most simple kind of "intelligence", namely, "awareness" or "consciousness"?

    could any thing do anything with another thing (like react with or repel from or attract to) if it was not, in some sense, aware of there being a compatible, or attractive or aversive entity for interaction. granted, this is not "thought". there is no chemical saying to itself, "this chemical over here looks good", but does this mean that there is not awareness, or does it mean that we have a misconception of the nature, meaning, reality of "awareness"?
  5. Jan 24, 2006 #4
    this is very similar to how i first joined this forum a year ago, if you want to you can dig through the old threads and see what was written, i remeber honestRoseWater answered a question of mine very nicely, her responce might help u. (sry i cant remember the name)
  6. Jan 26, 2006 #5
    This might be true, but consider the logical conslusions if it is. We, humans, are nothing more then matter in motion like a rock in space. Alright, we're a comlpicated rock that somehow managed to delude itself into believing it is better then the rest of the universe around it. Well, if this is true then it destroyers any type of philosophy we have, especially morals. Think about it, I can do whatever I want because you are nothing more then a hunk of organic matterial. I can kill you, torture you, steal from you and not worry about it in the slightest. This destroys the idea that humans are equal, that humans have rights; and this is the tenent all our laws are based on. Destroy it and we are left with no foundation for society. Do anyone of us actually want this?
    Its really simple: you can believe that there is more to humans then matter and motion, or you can believe that there isn't. It's really a conundrum similar to whether god exists. You can't prove it one way or another, and so the only position is an agnostic. Same with this problem, and I for one choose to believe that I'm better then the flies I swat everyday.
  7. Jan 26, 2006 #6


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    I think you're conflating two different ideas here: concept that we live in a radically godless world, and the idea that we are mechanism. As many many threads on these Philosophy boards go to show, these ideas are not necessarily linked. We could imagine a god who created us as mechanisms, and the mystically inclined will assert that their claim we are more than mechanism in no way implies theism.

    And from either side, the moral position is not so bad as you state.

    Philosophers after Nietsche and Sartre have erected god-free schemes of morality, or ethics: Rawls comes to mind. Sartre himself asserted that we cannot understand our own freedom except in a context of general freedom, so that acknowledging ourselves to be free, as his existentialism requires us to do, necessitates acknowledging the freedom of others.

    As to the mechanism side of the issue, Dennett wrote a book called Freedom Evolves which states a sort of "evolutionized" version of compatibilism. This position is that though in the last analysis we may be deterministic machines, yet at the conscious level, in every HUMAN sense of the word, we find ourselves to be free.
  8. Jan 26, 2006 #7
    And for those that need so badly to be distinct from other living organisms, the only thing that is needed is to recognize this higher level of consciousness, and roll around in it a little. It truly is a much more profound idea than that of humans being created by 'intelligent design'.
  9. Jan 26, 2006 #8
    Sure, this works theoreticly, but then again so does communism. We all know how that turned out. To truly be effective, philosophy must be placed in a practical light, otherwise its worthless in real-life. Using Sartre's claim that existentialism requires us to acknowledge other people's freedom before ours, I ask why? Why can't I be free to do what I want, even if it violates your "rights". What makes us equal if we're nothing more then smart animals? We treat animals in ways we never would do so to humans, so if you're an animal I can kill you as easily as swating a mosquito. This is of course unthinkable, and thus is discarded by any rational person.
    However, claiming that humans have rights leave only two choices. One, all animals have human rights. Under this moral code you couldn't swat a mosquito biting you: it is obviously impractical. Second choice: we are more then animals and so have rights they don't. This is the only practical choice of the two, and its always been the one adopted.
    The question then becomes why are we better then animals? Is it because we're smarter? If this is the case, then our complicated brain is the only improvment and we are nothing more then organic machines. This makes us equal to animals, so it can't be the case. We must then inherently possess something animals never can, something that is beyond the mere process of chemical reactions. This is the idea that we have a soul. Whether or not there is a god involved is irrelevent, as is the nature of the soul. What matters is that a soul is something above and beyond mere chemical reactions, and it differs us from animals. Once again, proof of this is as of yet impossible, and I see not way to ever prove it, but it is the only aproach that can be applied to life.

    I only used the analogy of whether god exists as an example of another unprovable problem of philosophy. I'm sorry for any confusion this might have caused. You're right of course, a god could have made us as mechanisms, and I never intended to use theism as proof of my arguments.
  10. Jan 27, 2006 #9
    In a less complicated way I'd say we are walking and talking mud. Just add water, hydrogen sulfide, some other minerals and a temperature of over 400º C with agitation and, wallah, neucleotides.

    This process may not have happend on this planet, though. Viruses from other planets can and do arrive on earth from time to time. They are crystaline in nature and survive intact over great distances and long periods. They're in a dormant state to do this.

    Once they landed here, after evolving their RNA strands elsewhere, it's not a far stretch to imagine the RNA stand from one virus combining with an RNA strand of another type of virus in the first step toward developing DNA. Add the similar minerals and conditions previously mentioned plus time and "kapow"... Tube worms.

    Practically every aboriginal culture has a creation myth that suggests humans were made from mud. From there, its all rock and roll!
  11. Jan 27, 2006 #10
    What about..

    This above point and the initial idea in this thread of humans or animals being very complex chemical reactions seems to leave out the "hard problem of consciousness"

    Without the experiences inside our heads this universe would be much easier to conceptulise (though there would be no one to conceptulise it), as biology is explained by chemistry and chemisty explained by physics.

    As tempting as it is to have a simplistic, coherent view of the world (I would love this too) it seems that there is a difference between subconscious brain processes going on in my head (just chemical reactions) and conscious processes, chemical reactions accompanied by experience.

    Excatly what experiences are, why they seem to accompany certain brain processes and not others, and how they fit into the natural world is a very confusing question that throws a spanner in the works of any materialistic reductive view of animals.

    Also in regards to comments of freedom of choice above, I do not think the the moral consequences of us not having freedom of choice is something that should come into consideration when deciding the truth of the matter. If it did turn out that all the evidence showed all behavior is brain based well then thats the way it is. Desiring accountability is not a form of evidence against scientific evidence for determinism.
  12. Jan 27, 2006 #11


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    Do we? Some think it has never been tried, just like Christianity. But that's for another thread.

    If you act that way you are denying your own freedom, which always gives you the choice to act according to the freedom of others. I repeat, what Sartre claimed is that your freedom is logically inseparable from the freedom of others.

    Yes, and discarded without any reference to god.

    The difference is that we can frame the question. If some species of animal other than us could also do that they would also be free and fall under the philosophical cloak of justice. Animals that cannot conceive justice may or may not have rights, opinions differ, but not because they are animals - we are animals too! - but because they cannot conceive of justice or reciprocity.

    As you see I can deny your premise without illogic.

    Soulessness is equally interesting:biggrin:
    Last edited: Jan 27, 2006
  13. Jan 27, 2006 #12
    I don't exactly know from your statement your stance on how our soul came to be but... just so you know mine, i'm speaking from an agnostic perspective. Our soul, or whatever you choose to call it, IS what makes us better than animals (or should I say organic life in general). There are numerous examples of living things living and grouping together socially. (I would list some but I don't want to insult anyones intelligence). Yet there is only one that has the capability to "know" we can disobey our instincts, and act anyway we see fit to do. Luckily, we have also the foresight to look ahead into the future and see that this could be very a self-destructive feature of our awareness. (and usually is--just turn on the news) Thus, we create laws, superstition, fear, to controll those urges of self-destruction. It might be that it is just a means to an end of furthering the life of the human animal, but it does make us, in my opinion, better. Some might argue that this makes us worse than the animals. To them I will quote kcballer21.

    Right on!!!
  14. Jan 27, 2006 #13
    Sure, we can frame the question but you aren't taking this logicaly all the way. Why can we frame the question? Is it becuase we have more complex brains? Why then does this make us superior?

    Certain animals can concieve of reciprocity. A grizzly bear mother who thinks you are a danger to her cubs will simply chase you away. If you harm or kill one of the cubs, she will not stop pursuing you until she kills you, or until you somehow manage to escape. Even then she does her utmost to kill you. In this, the grizzly bear demonstrates vengance and reciprocity even in the animal world.
  15. Jan 28, 2006 #14

    What do you mean by 'causal mechanism'? So you mean that humans are like 'functions', where with a given set of parameters( genes, environments) or other input values, there corresponds to a set of external outputs?
  16. Jan 28, 2006 #15
    what about natural tribes and cultures?

    In those cultures you rarely see anyone not obeying the leader's orders.

    Murder and theft, for example, are only a "luxurios features" of our culture, in the so called modern world. You can find it very often in our world, you will rarely find it in cultures of natural tribes. Possessions of things isn't known in their world, too, hence they don't have anything to steal, because everything is collected good (like Marx' idea of communism).
  17. Jan 28, 2006 #16
    Notice you said "rarely". To say murder and theft are luxuries of the modern world is not a valid statement. Their were certainly examples of this in ancient egypt (if we are reading the language correctly). They were not "modern". Maybe they might be described as "civilized". I'm not an expert on Indian culture, (either native american, african, etc.) but I can't think of a one that didn't use some form of a "diety" as a means of controlling the population. Any "ism" you want to use has some key element of control. Now, is our proclivity toward being controlled a matter of some random chemical/physical reactions to outside stimuli? You can argue both I guess. I surely don't have the answer to that one. I certainly feel like I can disobey my "casual mechanism".
  18. Jan 28, 2006 #17
    Consciousness is not a hard problem. It is the result of our physiology and natural selection/evolution.

    Consciousness is simply the effect caused by the complex result of our evolution. Compare it to the various differences we see in animals and plants.

    Eg. some butterflies have developed large spots on their wings that look like big eyes to their preditors... the butterfly with the spots didn't develope the spots consciously, as a way to survive... the butterflys with the larger spots were selected by trial and error to be the dominant family of their sub-species because they survived longer and reproduced more offspring due to warding off predators.

    Consciousness is the same effect. It is caused by the function of natural selection and now Humans are stuck with it. At one time it served as a dominant feature, ensuring the continuation of the species and its reproduction... but, today, it seems to be having the reverse effect... considering over-population, special interests like humans thinking their better than nature or whathaveyou.

    The very existence of consciousness may have a mechanistic function in the evolution of the universe but, its not like we'll ever "know" about it or what the function is. Some people say the universe is growing a brain... just the same way mud grew a brain and called itself human... but, that is a biopomorphic view... and we would be the most biased commentators on the subject.
  19. Jan 28, 2006 #18
    Really? Enlighten us on how you know this as a stated fact. A butterfly having spots does not explain how a conciousness evolves. Not that evolution doesn't factor into the equation, I'll give you that.

    Is this really an example of reciprocity? If we take this to mean that every time you kill a bear cub, every time the bear will try to kill you. This is more like an unconcious decicion. An instinct if you will. Where we differ is the ability to either kill you or not kill you. An example, if I accidentaly killed a bear cub, the bear would not see it as an accident, and instinctivly try to kill me. A human might be just as inclined to kill you, but can conciously choose not to.
  20. Jan 28, 2006 #19
    Natural selection selects for heritable traits, those which can be a product of our genes as these are all we can pass on to our ancestors. Genes make protiens and protiens do things in the brain like send signals or open membranes. It seems quite possible a brain could be a completly physical thing, performing the physical actions, with as much experience as a rock.

    If it is possible for a brain to function without experiences (I think this is intuitivly obvious but let me know if you want an argument) then experiences must be something more than brain function. This leads to the famous mind body problem: what are experiences and how do they fit into the physical world. There are many famous philosophers (Dennet, Chalmers, Churchland, Searle, Jackson) who have very different opinions on this problem and i don't think any of them would say it is an easy problem.

    Saying consciousness is a product of our genes gets back to the same problem of how does something physical, genes, make something none physical, experience. If you define experience as a physical then you have to explain why (logically speaking) brains could exist without experiences, despite having all the physical components we know of present.

    If they brain is truly physical why have experiences at all, a thermostat doesn't need to experience hot or cold to turn my heater off, on an incredibly more complex scale why does my physical brain have to feel cold to put a jacket on.
  21. Jan 28, 2006 #20
    This really is a continuation of a problem goes as far back as Blaise Pascal. I ask one simple question: if we are nothing more then smart animals then why do we think? Animals can't reason no matter how smart they are. There are some very intellegent animals in the world but not a single one of them can reason. Why? Biologicaly our brains aren't that different from their's, so why do we have this special gift that they don't? Chemical reactions are non-thinking, non-reasoning. They simply are. We are different. We can choose to do one thing or the other, we can make our decisions. There is more to us then binary choices. This is self evidant. It needs no empirical proof becuase it simply is.
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