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Determinism Question - possibility of scientific explanations for human behaviour

  1. Jun 23, 2011 #1
    Hmmm. I hope you will understand my slight nervousness at posting on the philosophy forum with all of its tight rules and circling, predatory mentors. My hope is that by following your instructions closely I’ll avoid the awful finality of those thread closing talons.

    So, moved from the Homosexuality thread on the Biology forum:

    Yes, Ryan, I take the point about just how complex a question this is in terms of hoping that science will ever be able to provide anything close to definitive answers. I wonder if I might coax you into answering a particular point of interest to me. I am conscious that I might be accused of going off-topic, my hope is that people – and in particular the OP - can see that I am only actually stretching the principle that underlies the question of a genetic programming for homosexuality. Perhaps the bigger problem is that, as I do understand and with all due acknowledgement of your knowledge and expertise Ryan, I am inviting you to make a speculative response. But I am interested in your thoughts.

    In any case, the point is that greater minds than mine have spoken of the possibility that every human action, every human decision, would have its ultimate explanation down in the quantum interactions of the atoms and subatomic particles that make up the brain – or perhaps it would be better to say the central nervous system. The contrary view would be that somewhere between the quantum level and the actual behaviour of a human individual, there are points at which some level of not randomness necessarily, but certainly some form of scientific unpredictability operates.

    Perhaps I can better relate it in this way: If you watch the water coming over the edge at Niagara Falls, you might take the ‘clockwork’ view of the universe and believe that, however hopelessly complex an endeavour it would be, theoretically it would be possible to trace the interaction of every atom in every molecule of water – and all the impurities in the water – and give a precise explanation for how every droplet of water broke away from the main body as it came over the edge; how every splash at the bottom of the falls leaped to the height that it did, how every bubble of foam was caused to appear. Alternatively, you might think that the universe is not so clockwork, and that something of the uncertainty of the quantum world ultimately makes it impossible to explain every action of the water as it comes over the edge, no matter how great the endeavour made to explain it.

    And, absolutely vitally, let me make it clear, I am not trying to make some deeply philosophical point about the dignity of human life rising above the inherent reductionism of science, I am just interested in what someone with your kind of expertise in biology particularly and understanding of broader science generally feels about that. Is it likely that we are ultimately, a prisoner of our genes, of the chemical reactions that drive us, of the quantum interactions that underlie those chemical reactions, such that theoretically, one day science might be able to completely explain us? Or do you think that such a question is doomed to remain for ever more a purely philosophical one? Or do you not care to speculate? I quite understand if you don’t.
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  3. Jun 23, 2011 #2


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    Advocates of strong determinism posit that the universe is fundamentally predictable, the implication is if one were to reset an isolated system back to an earlier configuration it would proceed the exact same way as before.

    In this model if we were capable of observing all of all the fundamental components of a system (when I was studying this in school I always gave it with the caveat "observing in a totally non-interfering manner" which I believe is probably physically impossible) and we had sufficient computational power we could predict future configurations.

    Obviously this runs into practical problems of if it is actually possible to monitor a system without changing the parameters, if your monitoring was passive rather than active (i.e. sensing rather than scanning) this may be possible but within this universe there are no isolated systems and the act of sensing something could disrupt the system to proceed differently than if it had not been sensed. There is also the issue of sufficient computation, thanks to good old chaos even if we could monitor complex dynamic systems (such as the climate or the human body) at a highly detailed level slight variations that slip under our radar could produce radically different outcomes.

    To address the issue of quantum randomness I am not an expert in this field so my views may be wrong. However as I understand it in classical physics we could describe things in a deterministic manner i.e. if the exact same system is set up twice it will proceed in precisely the same way. However at the quantum scale things become less deterministic and more probabilistic. So if we were to try to simulate a system from the quantum level we could produce a simulation that explores the system's phase space giving us a variety of options all with differing probabilities. Essentially this means that a classical molecular dynamic simulation would give us the same result each time whereas a simulation at the quantum level would give us the same result but with a probability attached along with a series of slightly different scenarios with lower probability. In my mind this is akin to an http://www.dillgroup.ucsf.edu/dl_images/funnel/bumpyBowl.jpeg [Broken] similar to that theorised for protein folding.

    Lastly to address the notions of what "we" are. Despite the fact that either system, deterministic or probabilistic, leaves little room for free will et al it still leaves space for consciousness as an emergent property of the system. It also doesn't dispel the illusion of free will and to all practical purposes our actions in life can still be judged as if we had consciously chosen to do them (whatever that means).
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  4. Jun 23, 2011 #3


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    Strong determinism fails to deal with the issue of emergence. If more is different, as so many recognise, then new causation "pops out" at higher levels of complexity. Any lower level theory constructed on strong determinism cannot model what emerges.

    The claim would be that the lower level theory would be sufficient to simulate what emerges. That is, replicate all a system's lower level design and exactly the same higher level stuff would again "pop out". But a simulation is not the same thing as a scientific theory. Observing a result is different from predicting it.

    And all this is before we correctly get into the discussion whether reality is actually micro-determinate (it is patently not), and whether initial conditions can ever be measured with sufficient accuracy (clearly this is also a real issue).

    Strong determinism is fine as a modelling principle. It is a useful presumption for certain kinds of theory building. But when it becomes an article of faith, a belief about reality, then science tips over into irrationality.
  5. Jun 23, 2011 #4
    I am still not completely certain that formal philosophical determinism as described in the Wiki article that you linked to Ryan, is exactly what I was actually thinking of. Although reading through the article does help me gain some certainty about my own view. Firstly, fatalism I have no problem rejecting directly and unequivocally. If I drive to work in the morning with the attitude that it doesn’t matter how I drive because if I am fated to die in a car accident then nothing I do is going to change that, then I can significantly increase the probability of that outcome. I have no problem recognising that I can affect the outcome and that I need to drive with care to keep that possibility to a minimum.

    And it definitely seems to me that this is not just the same thing as the nature / nurture debate. I think it is clear enough that some aspects of human behaviour have their basis primarily in genetic programming and others owe a great deal to environmental influences with many being subtle mixtures of the two. But I don’t see that necessarily answering the question of whether a particular choice made or action taken by an individual can be traced through the various levels of interactions down to the quantum interactions of the sub atomic particles that make up the nervous system of that individual.

    Perhaps there is more insight in pondering this notion of resetting the initial circumstances and getting exactly the same outcome. I could believe in the possibility with my Niagara Falls example, and I am happy to ignore this issue of practicality of the measuring system interacting with the test. Let’s just say the initial circumstances were exactly recreated by the most outrageous and unlikely coincidence. It seems credible to me that the outcome could then be exactly the same as the previous time. But if you were to reset the evolutionary clock to the time of the first single celled organism, with all other circumstances perfectly recreated, it seems to me that the outcome would be different. It might be inevitable that evolution would recur in something of a very similar way, and the end result might be recognisably similar to what we have today, with land based life forms evolved from sea based life forms, complex interacting eco systems involving plant life and animal life with lots of specialist niche fillers leading to a vast diversity of species ranging from tiny insect like species to great mega fauna. But the particularities, it seems to me, would inevitably be different. And I suppose that the distinction that I am drawing is that ultimately, Niagara Falls is a purely mechanical beast, whereas evolution involves this mysterious phenomenon called life.

    I retain my feeling that we human beings are more than just a prisoner of our genes, though I don’t doubt that we are heavily subject to their influence.
  6. Jun 24, 2011 #5


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    It's of course the interaction between genes and external stimulus, not one or the other.

    Another point that's missed a lot is developmental. The experiences from time spent in the womb can lead to life long changes in humans.

    Humans are highly determinatic in their behavior in my opinion. But it goes beyond genes to social and developmental aspects (as well as physical happenstance).

    The brain (as is commonly accepted and cited here at PF) is not a quantum in terms of the information processing that occurs.

    But electrochemical systems can be nondeterministic (see Prigogine). Modern physics is not only GR and QM, there's a lot of interest in dissipative systems as well; we are dissipative systems, but does dissipation have a significant effect on our choices that somehow allows us to be an independent agent that makes decisions despite the deterministic chain we are part of?

    I strongly doubt it...
  7. Jun 24, 2011 #6


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    I would disagree, it is the same principle. Compared to Niagara falls we are of course different but all the molecules of our body obey the same principles. With the exception of quantum behaviour (which effects chemistry) if you reset a system with life inside it will progress exactly the same. Life is a semi-ambiguous label that we apply to self-replicating structures made of sacs of chemicals, intrinsically there is no difference to the processes that underlie life and non-life.

    If I could continue the analogy, we are a prisoner of our genes but the walls are over the horizon. Our genes set up the boundaries of what we are capable of by providing the basic platform for how our body has assembled and maintains itself. But genes aren't written laws they are more like the foundations of our biochemistry. Genes code for proteins which are the tools we use to run a metabolism, obviously we are restricted but the scope for what we can do is wide.
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  8. Jun 24, 2011 #7
    Well Ryan, now, for me, we are much closer to the heart of the matter. It emerges that we do disagree – with all due defence to your greater knowledge and understanding of the biology, I stand by my view. I want to expand on why, but I’m very conscious of the danger that this post might become too long. So, as direct and concise as I can make it:

    Instead of genes and homosexuality, which seems to exercise the minds of many people judging by my experience on forums like this, for me, where this really becomes an important issue is on the matter of criminal behaviour. It seems clear to me that the behaviour that comes from our genes is essentially to behave selfishly, to serve our own narrow interests whatever the cost to others. A system of criminal justice then has to be based on the belief that we have the capability to overcome this and to recognise a need to adhere to the rules in the greater interests of society. Now at that point I will have to mention that I am very aware of the issue of altruism as a genetically programmed behaviour and the evolutionary purpose of it. In humans, its manifestation is most apparent in our kin relationships. But I would suggest that it is just a subtlety, an added complexity to the situation. Fundamentally, our genes equip us to look after ourselves and not to care about others, certainly not those beyond our kin relationships or those with whom we mate.

    Now at this point I am going to bring in a great classic work of literature – Heart of Darkness by Joseph Conrad. It is credited as being a key part of the inspiration for William Golding’s novel Lord of the Flies which takes a very similar view of humanity and it is, of course, also the original on which the film Apocalypse Now is based. Now Conrad, of course, knew nothing of ideas of behaviours based in the genes, much less the quantum interactions of the molecules and atoms of which we are made. Neither, I believe, were his thoughts based on the formal philosophical idea of determinism. But his story certainly was inspired by the observation of real human behaviour – centrally among ivory traders in the Congo. And essentially, the idea that Conrad portrays is that the behaviour that is ‘natural’ to us, more than simply selfish, is downright barbaric. Civilised behaviour is something that we learn, and it is a thin veneer that is very easily stripped away. As thinkers other than Conrad have pointed out, the concept of a ‘conscience’ is not about an inherent drive to be good, but about the concern for how others perceive us. The flip side is that shame is not actually about what we did wrong, but about the knowledge that others know what we did and judge us badly for doing it. The suggestion is that, however indignant anyone might be at the mere suggestion that they could ever behave in a criminal manner, if faced with an opportunity for personal advantage at the expense of others, coupled with the feeling of certainty that no-one will ever know, everyone is capable of taking that advantage.

    As I am sure you can see, it is this that makes the idea that every individual decision is governed by the mechanics of our constituent parts seriously problematic. Personally, I dislike your analogy of freedom to move within ultimate confines set by the genes. As I see it, and, it seems to me, as any system of criminal justice must see it, it is more of a case that we have the ability to bring our emergent intelligence to bear, allowing us to overcome our baser instincts to make a better judgement. And the responsibility for that is ours, not that of our genes or the interactions of our fundamental constituents.
  9. Jun 24, 2011 #8


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    I think we should change slightly our terminology. So far it has been useful to talk about "genes" but in reality this means that we are simplifying the issue, to delve deeper we are going to have to leave that word behind. Genes are simply sequences of DNA that can be transcribed into mRNA then translated into proteins, they (by and large) do not code for gross characteristics. By this I mean there is no gene for height, nor for anger or intelligence (these things are ultimately a product of our genome, epigenome, proteome and phenome most likely with a few other "-omes" I've missed out). Our DNA is the backbone of our biochemistry which ultimately results in our bodies. By saying our genes decide our limitations I meant to mean our bodies decide our limitations. The same way my body limits me in breathing underwater it also limits me in the thoughts and emotions that I can feel. However there is obviously huge scope for what we can think and feel. So onto some of your points,

    With respect I think this is simplified on two counts; firstly not all criminal behaviour is due to selfishness, it may be a crime that the criminal deems to not harm anyone (e.g. smoking weed) it may be done out of desperation or, far more interestingly in terms of our discussion, may be done to protect peers and a way of life. In this respect criminality is a set of societal actions that are at odds with the greater society they live in, gang crime fits this bill for me.

    Perhaps a better way to look at crime is that those who commit certain crimes, essentially those that directly hurt people, have a lack of http://en.wikipedia.org/wiki/Empathy" [Broken] for some other people. It is possible for a violent thug to feel the same care, empathy and loyalty to his peers as the rest of us do to ours. The difference is the lack of empathy for non-peers as well as a belief that violent behaviour is justified (or as is common amongst people I have met before, a belief that violent behaviour is not justified but a belief that it doesn't matter because they enjoy it anyway).

    Our bodies (and consequently our genes) give us the faculty to feel empathy and act as the http://en.wikipedia.org/wiki/Social_animal" [Broken]) lack the capability to act socially. Therefore the necessary premise of justice that all people are capable of being "good" (whatever that means) still holds.

    I would agree that selfish behaviour is natural to us but only because I have a problem with the word "selfish". It has been argued that there is such thing as a selfish act because we do things that make us feel good and thus there is a reward for altruistic any act we do (even those that disadvantage us).

    However on the subject of altruistism I do think it is fair to say that altruistic behaviour is natural to humans but only within groups that we identify as our "tribe", with a corresponding decrease to how altruistic we are prepared to be depending on how 'distant' the person is to us socially. This is what leads to family/friend groups as well as football team violence, nationstates and elitism. Humans like to band together, and unlike our ancient ancestors we have a myriad of different "tribes" to belong to at once (rather like a social http://en.wikipedia.org/wiki/Panarchy" [Broken]) for example my "tribes" could include the various friends I have, my family, my neighbours, my country etc. Each one is a separate groups of which I am a member.

    Our conscience is our evolved mechanism of social behaviour, in essence we all (baring mentally ill people) have the capacity to decide that something is right or wrong. This is what our bodies (by way of our genes) have given us. What decision we make is entirely down to culture, and there nature meets nurture in a typically sticky way again.
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  10. Jun 24, 2011 #9


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    What does it mean that the universe is fundamentally predictable? Does it mean that there exists a theoretical framework that can predict the outcome of any given physical experiment? Any measurement to an arbitrary accuracy?

    In my opinion, determinism as a state of the universe is meaningless. The universe cannot be "physically predictable", as if this was a property of the universe. It does not make sense. Its thesis is not a statement about physics, but rather a statement about logic. Or more accurately; a statement about how it makes sense to talk about physics. Determinism is essentially advocating causality, but this is interpreted in the wrong way. We think of causality as something that "happens", and that it is a intrinsic physical relation between physical events. I believe this is wrong. Causality is rather a logical relation between descriptions of physical events. It is a certain kind of correlation between descriptions of events, which makes it possible to use logic to reason about physics.
  11. Jun 24, 2011 #10


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    I'm sorry I don't quite see your point. Determinism is a proposal the the universe is inherently predictable thanks to causality, the difference is that determinism is used as a discussion in the context of free will implications in a causal universe and what exactly free will means.
  12. Jun 24, 2011 #11


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    What does it mean to be "inherently predictable"? That there could always be given an explanation as to why 'this' happened because 'that' happened? Or that it could theoretically be possible to predict to an arbitrary accuracy what will happen in the future?

    The problem with free will is that it is treated as an objective status of the will. As if the will could have a property that would make it "free". But it begs the question, what does it mean that the will is free? I don't think this question has anything at all to do with causality.
  13. Jun 24, 2011 #12


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    Yes it means that if one could observe all components of the universe without interfering one could work out both the past and the future. This has implications for http://en.wikipedia.org/wiki/Fatalism" [Broken] philosophies

    I agree a big problem with "free will" is the definition of it. Broadly the idea of free will (as espoused by many ideologies from religion to law) is that one could have made a different choice about an action. Determinism undermines this ideology by point out that the decision was inevitable. This has implications for certain ideolgies such as http://en.wikipedia.org/wiki/Compatibilist" [Broken] fatalism.
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  14. Jun 24, 2011 #13


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    Whatever we "work out" is on the basis of some given theoretical framework. The problem is that whatever we "work out" is relative to the model we use. All we ever do is describing and predicting future descriptions. This is the fundamental flaw in the belief that the universe is intrinsically predictable. Being predictable is not a physical status at all.
  15. Jun 24, 2011 #14


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    The idea of freewill is a religious/social construct and so not scientific. Every time the subject gets raised, it is because fall back into a sterile division between "what Newtonian mechanics says" and "what religious and romantic belief says".

    The scientific approach would be to realise that Newtonian mechanics is a limited model of the universe and really an incredibly bad basis for talking about neurobiological complexity. To even try to argue from a Newtonian starting point is a category error.

    An infodynamics approach, for instance, would say it is all about information and constraints.

    So a simple Newtonian system has simple constraints. All the information is present in a rather direct fashion regarding both initial conditions and boundary conditions. The situation reduces to a constructive tale of local effecient causation. Everything is determined by discrete, atomistic, pushes and pulls in good mechanical fashion. The boundary conditions are not changing. The initial conditions likewise are set once. So there is no need in this stylised description of a system to pay attention to material, formal or final cause. These are all frozen still and the system becomes just the determinstic play of its parts - the degrees of freedom represented by the local atomistic pushes and pulls, or the system's efficient causes.

    But complex systems are capable of actual development and change. The other three causes are not frozen but come into play and so must be tracked in the modelling.

    We see this with QM. Final and formal cause are an issue because the future constrains the past (the various ways the observer issue makes itself felt). Deterministic chaos is another example of how a larger model is required because initial conditions actually need to be pinned down with arbitrary precision. Again there is an observer issue that has to be part of the model. The global constraints have to be precisely specified - they have to be known information - and this is a source of dynamism in the modelling as no two global states of constraint need be the same. Newtonian mechanics is of course presuming they are, so can be left out of the modelling.

    So when it comes to modelling a complex system like a brain (a biologically evolved system embedded in turn in a memetically evolving culture), if you are going to insist on thinking in terms of efficient causality, you need to get a proper sense of the actual weight of atomistic actions involved.

    A simple Newtonian system like an ideal gas has a rigid set of initial conditions and boundary constraints (the full story of efficient, material, formal and final cause). The only information that needs to be measured is the position and momentum of a collection of particles, then all the rest follows deterministically from efficient cause.

    But with a brain, in a world which is a mix of the predictable and the unpredictable, which has been shaped by a history of millions of years of biological information, thousands of years of cultural information, and tens of years of developmental information, and tens of minutes or seconds of fairly immediate context, task and goal information - well, that is a heck of a lot more information specifying the system.

    So just boiling a brain down to a collection of efficient causes (which is NOT an adequate description) you can see it already looks nothing like the kind of Laplacean ideal gas version of a determinstic system. Even a chaotic system is incredibly simple compared.

    The information - the collection of determinstic acts - involved in any brain decision, any individual act of freewill, stretches back millions of years. An ideal gas has virtually no history. Once gone to equilbrium, it really has no history. But a brain is quite incredibly poised at some moment in a particular history.

    Diehard Newtonians, missing the point, will say yes but every step along the way to a brain's current state is deterministic, so its next instant is also determined. The only problem for science is to go and measure those prior events as the initial conditions of a Newtonian model.

    Well you could do that (except QM and deterministic chaos suggest perhaps you can't). But it would be an incredibly inefficient approach to modelling. In practice, we can already see it would be foolish to treat every single little atom of efficient cause in the history of an organism as of being of equal scale, of equal import (which is what the information theoretic approach would demand). Instead, we would want to coarse-grain. Some efficient causes are clearly going to be more proximate than others.

    If I am sat at the lights about to turn green, what determines my next action (while also allowing me to be a contrary devil and deciding to sit there blocking the traffic and listen to the angry honking of those behind)?

    Determinism of the kind that wants to insist that decision was inevitable and predictable since the big bang would have to give equal weight to every discernible event in my past light cone. Determinism of some more moderate kind would have to include the brain evolving experiences of my H.erectus forebears - so already the coarse-graining of the measurement of the initial conditions has begun. Determinism of a fairly practical kind we could actually recognise as science would just try to find something about me at that moment which explains why instead of doing the habitual thing (drive away) I instead did something out of the ordinary.

    Perhaps I was having some petit mal fit, or winning a stupid bet, or could see an ambulance coming down the other way. This could be taken as an efficient cause (because in good Newtonian fashion, all the other causes seem unchanged - all my knowledge and training of how to react to a green light stayed exactly the same). But it would be an incredibly coarse-grain notion of the reason that determined an action. And so totally specific to the context that it could not be generalised as an explanation of freewill, or choice making, in general.

    It could have been a fit, a bet, a "give way to emergency vehicles" rule, or any other number of possible efficient causes. Therefore we end up with the fairly useless model of the style: well, he would have driven off at the green light in usual circumstances, but various unmodellable micro-circumstances can drive different decisions.

    A better model of a choice-making system would take into account that there is dynamism in material, formal and final cause as well. These would not be frozen out in the description of a system but knobs and settings that could be twiddled. Then we would have instead a model of "usual behaviour" in interaction with "specific circumstances".

    ie: The kind of infodynamic models being pursued currently in neuroscience, such as the Bayesian Brain.

    Nothing can stop these medieval sounding debates about Newtonian determinism vs conscious freewill. It is a meme now entrenched because it embodies the popular understanding of a fundamental conflict between scientism and religious doctrine. That is why there is still "the battle that must be won".

    But Newtonian mechanics was a moment in time. Science has advanced hugely since then. The debate no longer reflects the state of human knowledge.

    And science has to give up the notion that all is determined, all is local, atomistic, efficient cause, just as much as the unscientific have to give up cherished notions such as "freewill" as a substantial (physically causal) property of an immaterial mind.
  16. Jun 24, 2011 #15


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    I like the following quote by Locke about free will: "I think the question is not proper, whether the will be free, but whether a man be free."

    There are so many misconceptions about free will, especially those which poses a conflict between determinism and free will.
  17. Jun 24, 2011 #16
    Care to explain those misconceptions?
  18. Jun 26, 2011 #17
    Believe me Ryan, I am not the type to climb on my high horse because you have called any part of my argument simplistic. I don’t promise to agree with you but I am grateful for the engagement. I can hope that you also get something worthwhile out of the exchange. I certainly do.

    In point of fact I do have some grasp of what you are talking about with regard to the realities of how the genotype translates into the phenotype of an organism, from having read Sean Carroll. He describes very accessibly how it is not the content of the gene as such that controls a phenotypic feature but rather the sequence in which the genes are expressed in the embryonic developmental process. I quite liked the analogy he used when he said something to the effect that wondering how the genotype of a human being and a chimpanzee can be so similar when the morphology of those species are so different is like wondering how a fitter and a plumber have essentially the same tools in their tool box. You can do a lot of different things with a spanner and a screwdriver. In any case, we do fall into this mode of talking about genes as if individual features are controlled by gene content whereas the reality is much more complex, but I suppose my perspective is that what we are really discussing is what part of our behaviours are phenotypic and what parts are emergent.

    I suppose that I wasn’t really getting into some of the more subtle complexities of some things we see fit to criminalise when others may question exactly who the victim is. I was thinking more generically that the basic conflict of interest is between your own narrow interests and the recognition of greater benefit to everyone from more co-operative behaviour. Some think that an every man for himself approach is legitimate, most of us understand that such an approach doesn’t get us very far. Something like this is the underlying philosophy for a system of criminal justice, I think.

    And on the matter of altruism, just to be clear, it is something that has been quite extensively studied and researched, perhaps most famously by a biologist named William Hamilton, but there is a clear evolutionary explanation for the behaviour based purely on the idea of propagating the maximum number of copies of your own genes. And there is, surprisingly, a quite rigid mathematical formula that expresses the concept, based on degree of relatedness. Some wag, I forget exactly who, made a joke about how he would jump into a river to save two of his brothers, but only for four of his cousins, or eight of his second cousins, etc.

    Anyway, as you have suggested on the original homosexuality thread in the biology forum, these things are unlikely to have a robust and rigorous scientific explanation any time soon, so this all only remains our respective speculations. But it is still a tantalising and fascinating thing to try to understand.
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  19. Jun 27, 2011 #18


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    Yeah I remember Hamiltonian Altruism from my undergrad, it's neat and everything but it doesn't take into account how nurture effects it (especially in humans!). You're right though, it is a fascinating subject but we're going to have to wait for a better understanding to track back what makes us, us.
  20. Jul 14, 2011 #19


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    I'm a mathematics major, and I'll offer my opinion for what it is worth.

    At one time, I use to be a very firm believer in determinism. In fact, I deeply desired a deterministic universe because its rational and fits into a narrative of certainty. But the evidence against my deterministic faith piled so high that I could no longer ignore it. For thousands of years, mathematicians and scientists have attempted to rationalize the universe, and every single effort to do so has failed. The last nail in the coffin in my mind was Godel's theorem of incompleteness and a few other proofs similar to it. If the universe is deterministic, it is pseudo-indeterministic, so we are not going to be able to reduce it down to a point of certainty. For all intents and purposes, we might as well treat the universe as indeterministic and random.

    Leibniz had a very interesting question. Take a paint brush and sling paint onto a graph paper. Afterwards, build an equation from the paint spots. What does the equation mean exactly? In truth, the equation is complete nonsense even if those dots were created through some kind of deterministic process (IE: you slinging the paint onto the graph paper). If all we can see is the dots, the process might as well be indeterministic. I think the quantum world really puts us into this situation. So to answer your question, I'm pretty sure that the universe cannot be reduced down to clockwork.

    I just wonder when the social sciences are going to drop the rational actor assumption.
  21. Aug 19, 2011 #20
    What do you guys think of this view?
    Majority => the way nature has been perceived by most is deterministic.

    Determinism is how one perceives the universe to follow simplistic and logical laws . For example, the moon orbiting the Earth at an instant: If one knows the newtonian equations, any future position may be determined.

    Einstein (the biggest mind of science) fought for determinism . He tried to reach for God's mind. Imagined himself in God's place (from a human perspective of God) ,and discovered the famous general and special theory of relativity. Being one of the main founders of quantum mechanics, he loathed the subject (as it defied logic and determinism) and died in disbelief when the discipline was actually being accepted by most scientists.

    Real truth:
    Very different from how its perceived by many.

    => Nature, at the fundamental level, is defined by the laws of quantum mechanics which are infact, probablisitic.
    Mind boggling proof => Double slit experiment ( Nature's conjuring trick): when you look, you alter the outcome of the experiment!!

    My opinion:

    God has hidden several mysteries within the universe (such as the double slit, particles travelling back in time, matter being created out of nothing i.e. the big bang). He wants us to research deeper and deeper into these and really appreciate what he'has created. If everything was really simple and predictable, then we probably wouldnt be impressed by most of the things around us or one could say, by the creativity of God.

    Probabilities are are assigned to things, that we do not, and can never have full knowledge of. This is actually higlighted by Heisenberg's uncertainty principle: 'one can never have full knowledge about the position and the momentum of a particle at the same time i.e the knowledge of a particles position results in loss of all of its momentum'.
    In a way, Probabilities are the best approximation to how we perceive a certain situation. It underlines the incapability of the human mind to understand the reality of nature and as a result predict outcomes.

    In a way, God has expressed these probabilities throughout nature. Summary : We can never fully understand the universe, and the uncertainty within a probabilistic world will always remain.
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