tag:blogger.com,1999:blog-1812431336777691886.post5132482267710086665..comments2024-02-29T03:57:00.088-05:00Comments on The Mermaid's Tale: Another look at 'complexity'Anne Buchananhttp://www.blogger.com/profile/09212151396672651221noreply@blogger.comBlogger9125tag:blogger.com,1999:blog-1812431336777691886.post-87658685217502145902016-05-25T15:41:08.573-04:002016-05-25T15:41:08.573-04:00Sean Carrol's recent book, "The Big Pictu...Sean Carrol's recent book, "The Big Picture On the Origins of Life, Meaning, and the Universe Itself" has much to say on this broad topic, and I highly recommend it. For one provocative example, he declares causation an emergent, but not fundamental property of the universe: a highly useful way off talking about things. Her refers to his perspective as poetic naturalism. I found it compelling.John R. Vokeyhttps://www.blogger.com/profile/03822243132435056442noreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-73171187128185631482016-05-22T09:21:19.837-04:002016-05-22T09:21:19.837-04:00We're now in the realm of semantics and differ...We're now in the realm of semantics and differences in view of the value and constraints provided by metaphor and simile. If there is a truth out there, our meandering path to it can take many directions, mainly unpredictable. We can each hope, I think, that the usages we find helpful really are helpful.Ken Weisshttps://www.blogger.com/profile/02049713123559138421noreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-35141180026166313262016-05-21T21:19:32.351-04:002016-05-21T21:19:32.351-04:00But computation in a generic sense is ubiquitous: ...But computation in a generic sense is ubiquitous: receptor expression, hormone and cytokine secretion, cell differentiation, all 'interpreting' and influencing subsystems of organismal states.<br /><br />Yes. Exactly. I'd state it more strongly than that: anything you actually find and explicate going on in the brain is going to be computation. The _architecture_ of the brain isn't going to look very much like a generic "computer", but everything it does is going to be computation. That's why I get worried when people decide they dislike the computer metaphor: it may mean that they are looking for something that can't possibly be there, or are missing important constraints on how things might work.<br />David J. Littleboynoreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-38079654937486153882016-05-21T12:38:37.331-04:002016-05-21T12:38:37.331-04:00Thanks for these thoughts!
I think my take on the ...Thanks for these thoughts!<br />I think my take on the Aeon article is that our metaphors are products of our time, and our limitations. That doesn't make them wrong, perhaps, since the only real model is the real thing. So it's a message to be wary of similes and metaphors. <br /><br />The things you mention clearly (at least based on what current knowledge can show us) occur. There have been various plausible theories or catch-phrases, like 'canalization' that capture some of what you describe, and having done developmental work myself, I think there's a lot of truth there.<br /><br />However, one can, and to be a good scientist should, always ask whether what seems obvious can turn out to be wrong and/or limiting. The major scientific revolutions, to use Kuhn's over-invoked analysis, come with fundamental change of frameworks. Whether some metaphor other than computing and 'information' will serve us better remains to be seen. I always try to think about how things might be different, and I use computer simulation of evolution! But one can't just wish for deeper insights. Some facts or quirks, or luck, must come along for that to happen.Ken Weisshttps://www.blogger.com/profile/02049713123559138421noreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-66024382110847703402016-05-21T12:19:37.703-04:002016-05-21T12:19:37.703-04:00I'm not Littleboy, but thanks for your respons...I'm not Littleboy, but thanks for your response and link. Perhaps multilevel selection is partly responsible for the robusticity of developmental-genetic systems. The indirectness of organismic selection tends to, over time, spread out the genetic substrate of a trait, including modifying genes that ensure its expression and reduce any deleterious aspects. With the result that loss/substitution of single allele will be less likely to be fatally disruptive and beneficial traits will be likely to appear in different environments. Selection at the genic level results in multiple copies and segregation distortion of those genes indirectly selected.<br /><br />As for computation, our silicon digital computers are hardly a better metaphor than Descartes' hydraulic automata. But computation in a generic sense is ubiquitous: receptor expression, hormone and cytokine secretion, cell differentiation, all 'interpreting' and influencing subsystems of organismal states.<br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-74208364858454971642016-05-20T12:48:57.982-04:002016-05-20T12:48:57.982-04:00I don't remember exchanging comments with you ...I don't remember exchanging comments with you unless you were the 'anonymous' commenter above. I know very little about the brain but I have been writing computer programs for a long time and I think the analogy is forced. That the brain 'computes' or moves signal around in some way and 'stores' its experiences somehow seems obvious (and not magic!). But programs are 'linear' in the sense of one instruction following another in pre-prescribed order. I think it would have to be shown that there were similar pre-prescribed pathway orders in brains, in a very similar sense. Anyway, I have no deeper understanding of the motivation of the Aeon author, and our point was rather different, which was the basic idea of how complex causation works and the problems of trying to treat things in a reductionistic way when there are clearly multiple ways to achieve the same or similar outcomes (which may make things mysterious, but not mystical).Ken Weisshttps://www.blogger.com/profile/02049713123559138421noreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-56105962544620000532016-05-20T12:18:32.272-04:002016-05-20T12:18:32.272-04:00Sorry to be disagreeable again, but I disagree.
T...Sorry to be disagreeable again, but I disagree.<br /><br />The mathematics of computation answers the question of whether or not the brain is a computer quite clearly: the brain has to be a computer. There simply isn't anything the very simplest model of computation (the Turing machine) can't compute*. What this means is that the brain is either a computer of some sort, or it's magic. Really, there isn't anything else out there. The brain has to be a functional assemblage of functional parts that together creates a conscious thinking machine.<br /><br />Of course, that doesn't mean that the computer metaphor is particularly helpful (at least in it's current crudely applied forms) in understanding how the brain works, especially since our current understanding of what's going on in the brain is near zilch (we don't have the slightest clue how memories are stored: the latest is that the "memory reconsolidation" theory is probably simply wrong**). But if you look at the visual processing in the early stages of the optical system (edge detection and the like), you see very sensible circuits that do quite clear things. My bet is that it's like that all the way down, i.e. neural circuits implementing specific functions that are wired together so as to make a brain that works. (FWIW, I think the "neural networks" stuff is all barking up the wrong tree, but that's another rant.)<br /><br />So, yes, we don't have a clue how the brain works, and no, the computer model is probably doing more harm than good. But as long as you don't believe in magic, that the brain is only performing chemical and electrical processes, then at some point, what it's doing has to be computation in the mathematical sense. Because that's all there is.<br /><br />And as a final egregiously off-topic rant: the Turing test, as described by Turing himself (not as described in popular press accounts) is actually a quite serious test in which humans and computers are pitted against one another in one of the hardest tasks for humans to perform well on: empathizing with someone of the opposite sex well enough pretend to be the other sex. (Turing only asks that the computer perform as well as your generic male in this task.)<br /><br />*: It may be possible to compute some things faster by using quantum entanglement, but that doesn't change the set of things that can be computed.<br />**: http://blogs.discovermagazine.com/neuroskeptic/2016/05/19/does-reconsolidation-exist/#.Vz81uml-PxsDavid J. Littleboynoreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-47755368055037734682016-05-20T09:00:36.199-04:002016-05-20T09:00:36.199-04:00These are points to think about. In a way, the id...These are points to think about. In a way, the ideas about 'systems' or 'complexity' relate to how the net result can persist but not the individual components. We mentioned 'phenogenetic drift' and work by Andreas Wagner in recent posts. Lots of people are thinking about the issue, but mostly trying to force it into reductionistic modes.<br /><br />A current Nature article about agricultural research (here: http://www.nature.com/news/the-race-to-create-super-crops-1.19943) is essentially making the same point. Evolution in biological nature works directly through traits and only indirectly through individual causal genetic elements. <br /><br />Human culture--history, the arts, language and so on--have similar attributes, I think. Reductionism has a powerful history but is only one way to view the nature of causation.Ken Weisshttps://www.blogger.com/profile/02049713123559138421noreply@blogger.comtag:blogger.com,1999:blog-1812431336777691886.post-70528227596036418632016-05-20T01:24:49.337-04:002016-05-20T01:24:49.337-04:00We need a taxonomy of modes of persistence: how th...We need a taxonomy of modes of persistence: how things are transmitted through time (remaining a recognizable thing). One suggestion:<br /><br />1. pristineness: unchanging original object - some crystals, manufactured objects<br />2. substitution: same object is gradually replaced - Ship of Theseus thought experiment, fossils (different materials), extracellular matrix (of course dynamic change often functional)<br />3. replication: mechanical copy - DNA replication, photocopy, 3D printing, computer 'memory' <br />4. reproduction: replicated component of thing interacts with local environment to generate thing developmentally - daughter cells, organisms, memories, transmitted ideas, language<br /><br />OK, it needs work. But perhaps it helps illustrate how organisms and thoughts are nothing like crystals or DNA, and transmitted ideas even less so. It also highlights the limitation of our metaphors. Note also that all of these are subject to decay/error. In the case of reproduction, fidelity depends on the local environment (intra-organism, niche etc.) and in some sense the notion that the feature/species/other entity is the same thing through time is something of a Platonic fiction.Anonymousnoreply@blogger.com