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Is There a Limit to Scientific Understanding?
- hprotagonist 9y agodidn’t Godel and Turing and Church and Heisenberg definitively answer this question in the affirmative for most of the first half of the 20th century? There exist an infinite number of questions of the physical world and in math alone that one can ask, whose answers are “we cannot know within the context of these axioms”. Somewhat by definition, these questions are generally somewhat uninteresting, but there sure are a lot of them.
- cdancette 9y agoThis doesn't really mean there's a limit to scientific understanding, just that there's an infinite amount of questions we can't have an answer for. But there could be an infinite number of questions we can have an answer for as well, thus there's no limit to our understanding.
- supergarfield 9y agoSomething being infinite doesn't mean it has no limit (I guess "boundary" would be a better term). If, for instance, it were impossible to answer any question about the strong interaction, I'd clearly call that a limit to our understanding, regardless of the infinity of things we can say about black holes.
- cdancette 9y agoI think we could understand why it is impossible answer this question, and this would be knowledge, and maybe tell us where to look next.
- hprotagonist 9y agoIn what way are those infinite unanswerable questions not a bound on understanding?
- mathattack 9y agoYes - in theory these types of questions exist. But are things like the common cold amongst these problems?
- hprotagonist 9y agoi would lump most questions about biological systems into this category, yes. (this is my research area) Biological systems become intractable really fast, and deterministic chaos rears it’s ugly head more than you might expect. The game isn’t “can we understand this fully”, normally. It’s more like “can we understand enough to usually be able to fix things when systems are egregiously out of whack”, and that we have a shot at.
- supergarfield 9y agoGödel's theorem does applies to mathematical systems of axioms, and I don't think it's clear how it translates to physics. To take an extreme example, you could answer any physical question about a universe that's made up of a single particle traveling in a straight line, even though doing so requires a mathematical system complex enough for Gödel's results to apply. On the other hand, there are a number of interesting undecidable questions (in ZF, the axiom of choice and the continuum hypothesis are examples).
- naasking 9y ago> To take an extreme example, you could answer any physical question about a universe that's made up of a single particle traveling in a straight line, even though doing so requires a mathematical system complex enough for Gödel's results to apply... ...using current models. It's not clear them at such models are ultimately needed.
- jules 9y agoDepends on your point of view. If you something is not knowable even in principle then maybe the question was wrong, like "how many angels can dance on the head of a pin?". A better answer is perhaps that there are things that we could in principle find out, but cannot because either: 1. We can't do the experiment in practice, such as building a particle accelerator much bigger than the LHC, or factoring a 100000 digit number. 2. It's too complicated and there's no simple description in terms of macroscopic variables, such as the earth's ecosystem.
- lootsauce 9y agoYou can explain away with reasons why something is not or will not be known. That makes it no less a limit to our understanding.
- jules 9y agoNot always; the unknowable information in quantum mechanics is simply not there. It's not that there is no way to get at the information in practice, it's not even that there is no way to get at the information in theory. It's even stronger: Bell's theorem proves that the information can't be there: simply assuming that the information is there already leads to conclusions that contradict experimental facts. The idea that there ought to be information comes from erroneously applying our everyday intuition to quantum mechanics.
- juicyfroot 9y agoThis. Godel's thereom frees the mind.
- gbacon 9y agoSee also Rice’s theorem [0]: In computability theory, Rice's theorem states that all non-trivial, semantic properties of programs are undecidable. A semantic property is one about the program's behavior (for instance, does the program terminate for all inputs), unlike a syntactic property (for instance, does the program contain an if-then-else statement). A property is non-trivial if it is neither true for every computable function, nor for no computable function. [0]: https://en.wikipedia.org/wiki/Rice's_theorem https://en.wikipedia.org/wiki/Rice's_theorem
- evincarofautumn 9y agoI think it’s worth noting that Rice’s theorem and the undecidability of the halting problem apply to arbitrary programs. In practice, the programs that humans write are very much non-arbitrary. Moreover, sometimes we’re happy to trade a bit of expressive power in exchange for stronger guarantees—like using a total/strongly-normalising language in which the answer to “Does this program terminate for all inputs?” is always “Yes”. In a similar vein, most real numbers are uncomputable, but we pretty much only care about the computable ones AFAIK.
- sremani 9y agoIts not The Atlantic article, its a repost of Aeon article. Here is the link to Original, https://aeon.co/ideas/black-holes-are-simpler-than-forests-and-science-has-its-limits https://aeon.co/ideas/black-holes-are-simpler-than-forests-a...
- everdev 9y agoThe article mostly argues that some concepts are too complex for humans to understand and that only though computers or post-human intelligence can we discover further scientific truths. But, the scientific process is independent of human intelligence. So, more interesting is: given an infinitely intelligent organism, can that organism be use the scientific process to completely understand the universe? Or, does science have a flaw that limits it's ability to explain certain truths?
- deleted 9y ago[deleted]
- aalleavitch 9y agoArguably, there are already many concepts that we as a society understand deeply but any individual human is completely incapable of grasping. Certainly, no single human could possibly hope to understand the whole sum of modern human knowledge; collectively we already constitute an intelligence billions of times more complex than a single human. In fact, there's a good argument to be made that the scientific process can't even work on the scale of a single human because it would be destroyed by bias; it's entirely in the notion of how you communicate and provide evidence for your theories to other people that the objectivity in science arises. When it comes to whether any intelligent system could understand the entire universe, I think at some point we start reaching the level where the terms of the question start to break down. What if we required an intelligence that spanned the entire universe in order to understand the universe? Is there maybe a sense in which we can say that the universe taken as a unit necessarily understands itself already? We start to rub up against very fundamental epistemological concepts that might not hold when we're considering a system vastly different from a human being.
- PoachedSausage 9y agoIn some ways the universe is aware of itself in the form of consciousness, if you believe its real of course.
- aalleavitch 9y ago
- SAI_Peregrinus 9y agoScience is a process to find objective truths. It relies upon consistency, if a counterexample is found to a theory that theory is considered incorrect. New theories must match all existing data. Einstein's theory of General Relativity is a good example of this; it replaces Newtonian gravitation in extreme circumstances but provides the exact same results in the limit around everyday energies. Science cannot create objective understanding of purely subjective systems. The issues surrounding consciousness and qualia are of this sort, while everyone experiences their reality they are inherently outside the domain of objective truth. The closest science can get is to consider them as "emergent phenomena" and give up on explaining the issue.
- coldtea 9y ago>Science is a process to find objective truths. There are no "objective truths" (that's metaphysics). Science is a process to find which models/hypotheses make more accurate predictions and have more explanatory power. >It relies upon consistency, if a counterexample is found to a theory that theory is considered incorrect. New theories must match all existing data. That (a popular but naive epistemology) doesn't hold with how scientific process actually works. New theories can have counterexamples or be unable to match all existing data and still be successful in providing a handier model for more phenomena. Theories might even be inconsistent with other theories (e.g. QM and relativity) and still co-exist and successfully grow while searching for a unification factor (whether that's successful or not). New theories can succeed (and historically have been known to) even when not accounting for all existing known facts predicted by earlier ones. In other words, more explanatory power doesn't necessarily mean a complete superset. The intersection might not cover 100%. And that's just for hard sciences. For soft sciences, from economics to social sciences, it's even fuzzier.
- aalleavitch 9y agoI'd say it's more accurate to say that science doesn't arrive at objective truths so much as shared truths. It arrives at truths that as many scientists as possible can agree upon. Consensus, after all, is the highest state a scientific theory can aspire to.
- cossatot 9y agoI think an additional limit is data. Particularly for sciences with strong path dependence, such as ecology, cosmology, evolutionary biology and (my field) geosciences, time has simply erased nearly all of the record of previous events. This is both a big problem (it is quite frustrating) and an opportunity, as we progress through both discovering new records of the past, and developing new techniques for analyzing existing records through new or improved proxies, instrumentation, or theory. I think it’s obvious to the practitioners that we will never know the vast majority of what we want to know, but we can learn enough of what we need to know to keep moving foreword.
- gniv 9y agoI was disappointed that the article doesn't mention machine learning. To me it's the perfect example of both the limits of our understanding, and how we can overcome them: Even though we don't understand how AlphaZero learns to master the game, we can use it to do so.
- monocularvision 9y agoSeveral times the article discusses using computers to further our understanding.
- hliyan 9y agoThis seems to be a problem of constructing approximate mental models to explain "emergent" properties of complex systems composed of interacting simple elements (such as atoms). I would like to think that such explanations aren't always necessary, so long as a computer simulation of the simpler (and well understood) elements can reproduce the emergent behavior. It seems to be a limitation of human working memory rather than some theoretical limit to comprehension.
- incadenza 9y agoI agree. To model any complex system, it only really requires that a person or a group of people understand, and are able to codify their knowledge the system for a given period of time. Just think of your average decently sized code base. There's enough complexity there such that any single human can't understand it at a given time, save for a very high-level explanation. Does this mean that we don't understand the code base? I don't know if that's the right way to think about it.
- lr4444lr 9y agoExcept that there is no emergent property of code. It is the sum of its logical parts, no more, no less. Any emergent value requires our conscious design.
- naasking 9y ago> Except that there is no emergent property of code. It is the sum of its logical parts, no more, no less Why do you think emergent properties are not the sum of their parts? If I may simplify, there are generally two classes of emergence, metaphysical and epistemic. The former claims that systems are more than the sum of their parts, that some magic happens when some combination of things are brought together. Few people in science or philosophy takes this position seriously. Epistemic emergence is more about what approach to use to learn about a system. Science is typically reductionist, and it's very successful. However, some properties would be difficult to discover this way because they are only observed in complex interactions between multiple entwined subsystems. For a simplistic example, consider a scenario where you know nothing about physics, but are given unlimited time and unlimited tools to separately test the properties of oxygen molecules, and hydrogen molecules. But, you can never test them together, only separately. Given these constraints, it seems virtually impossible to infer the property that H2O is transparent to visual light. But this property is easy to see when studying them together. Epistemic emergence would hold that we maybe couldn't learn everything about hydrogen and oxygen by studying them separately, or at the very least, doing so isn't always the most effective means to learn about them. But ultimately, the properties revealed of H and O belong to them, and aren't metaphysical.
- dwaltrip 9y agoThe most obvious limits are observational limits and comprehension/interpretation limits. This first is determined by the tools available, and thus technological and engineering advancements extend this limit. Of course, there are inherent difficulties that accumulate as we try to peer further and deeper, and I think it is likely we hit some practical barrier that is virtually impossible to get past. If for example, a thousand years from now, we need the energy from a million suns to fully verify that we have reached the bottom layer of physics, we may never be able to pull that off. Comprehension and interpretation limits seem fuzzier and trickier to speculate on -- but they definitely exist. We are running up against many of them right now with the complex systems we attempt to model. It seems that software tools and AI developments are the most obvious ways to continually push this forward, but there may be some deep difficulties and pragmatic barriers lurking here as well. There is a lot of room before we start hitting serious limits and overwhelming pragmatic difficulties. Once we have a highly utilized Dyson swarm, then we can reevaluate.
- LeifCarrotson 9y agoThe article and comments mention possible limits of understanding due to limitations on working memory: there could be a problem with so many moving parts that a human cannot keep all of them in consideration at one time. But people solve problems with huge numbers of moving parts all the time by breaking them into smaller modules. I wonder if the actual limit is due to human lifespans instead. There are certainly problems and sciences and systems that are understood through 12 years of primary education, followed by an undergraduate degree, increasing specialization in a masters degree, specialization and new discoveries beyond that in a doctoral degree, and then postdoctoral studies and professorial research far into the middle and end of a human lifespan. Perhaps there are problem domains which require 100 years of study amd education to comprehend before useful new research can be done.
- the8472 9y agoI think we're a long way off before reaching that limit. In research fundamental discoveries can take a genius many years of his career, but once it has been discovered the basic theory can often be taught an undergrad within a few months and adjacent discoveries will improve our understand and things easier to explain. Textbooks explaining it in 5 different ways will be written and our tooling improves etc. etc. You don't have to be fleming to grow penicillium, you don't have to be einstein to calculate relativistic corrections to GPS satellites. Eventually such diminishing returns might be reached if everything remained the same, but you also have to consider that IQ and lifespans are slowly ticking upwards over the decades and eventually we may be able to build a better researcher.
- Emma_Goldman 9y agoI agree that modulation and divisions of labour reduce the limits otherwise imposed by human working memory. I'm not sure that the same is not true of lifespans, namely, what kind of thinking cannot be sufficiently comprehended as to be tackled within one lifetime? I know of nothing, and this may be ignorance, that takes more than a PhD to comprehend (of course, one wants more than to comprehend, but one can begin to contribute once one comprehends). I was more thinking of the limits of humans ability to internally represent processes that we do not observe within quotidian life, and problems which requires such leaps of creative genius - like Einstein but 100x - that we cannot hope to traverse the chasm of our own stupidity in that singular moment of discovery.
- denzil_correa 9y agoYes, indeed there is a limit. However, this line of limit is the optimal line we (currently) have between "understanding everything" and "accepting every claim made".
- raverbashing 9y agoThe limit to scientific understanding could maybe be described as this: You're looking for explanations in the format P(x1,x2,x3...)->R where P is a "function" (the modeling of your theory), x1, x2 etc are measurable factors and R is a result Now, you can't measure all the factors, but you can have a good set of them that explains a result closely. Hence the question is, are there phenomena for which you can measure all the x's that give a good prediction for your result? (or even having good proxies for the x's) And that's not even going into the problem of establishing the theory in the first place In physics you can repeat experiments multiple times, few experiments are unethical and you can have very exact measurements. Now compare this with medicine. Also compare the difference between general predictions for a whole population to doing precise predictions for one specific individual. How many x's do you thing would affect risk of cancer/risk of cardiac disease or just the risk of a weird mutation that changes risks slightly (and that medicine hasn't even heard about it) There's your limit
- dsnuh 9y agoI'm not a PhD, but I always like to think of this explanation when trying to understand how progress happens. In bumps. http://matt.might.net/articles/phd-school-in-pictures/ http://matt.might.net/articles/phd-school-in-pictures/
- foolrush 9y agoLikely the False Narrative myth at work in a similar fashion to attributing a narrative structure to the universe for example. As a counterpoint, Foucault's Order of Things offers up a historical “archaeology” of the sciences congruent with power structures.
- Animats 9y agoThis is mostly a problem in biology. Biology doesn't have parsimony. There's no evolutionary drive towards simplicity. Biology is a collection of evolved patches. It can have much higher complexity that it would seem to need. Yet human DNA is only about 4GB. That's big, but not so big as to be beyond analysis. Without computer assistance, getting a handle on it would be hopeless, but we're past that point and making steady progress. (How complicated is physics? Things looked good in the era of Maxwell's equations, but it's become much messier since. In physics, much is out of reach of experiment due to being either too small (superstrings, if they exist) or too big (where's the missing mass and the antimatter? That's not an understanding problem. That's lack of experimental evidence.)
- whatshisface 9y ago>There's no evolutionary drive towards simplicity. There's a drive towards smallness (as in, lower food requirements) which has probably made simplicity a lot less bad than otherwise. >In physics, much is out of reach of experiment due to being either too small (superstrings, if they exist) In the era of Maxwell's equations, atoms were too small. Never under-estimate the power of cleverness and indirect observation! (Now days we can image atoms directly: but we needed to get our understand of them elsewhere in order for our technology to advance that far.) The jury's still out on strings; although plenty of people claim that we won't ever reach the energy scales necessasary to totally rule it out, we still might find something predicted by a lower-energy version, and maybe one day we'll uncover a new theoretical result that gives us an avenue we can't currently see. >or too big (where's the missing mass and the antimatter? That's not too big, we're expecting the answer in the form of slight asymmetries in particle interactions like the ones we're studying in the LHC.
- jules 9y agoIf we look back on the development of relativity and quantum mechanics with the benefit of hindsight we see that there were already many clues in classical physics. Perhaps our current experimental evidence and current theories have enough clues to make progress, but nobody has had the right idea yet.
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- Koshkin 9y agoWhy should there be a limit? Excluding cases when information is lost (or is somehow inaccessible in principle), everything can be investigated, learned and understood - given enough time and effort.
- digitalmaster 9y ago“The saddest aspect of life right now is that science gathers knowledge faster than society gathers wisdom.” - Isaac Asimov
- PoachedSausage 9y agoI've not heard that quote before, it sums things up nicely. Most of our problems are political/social. The phrase "wise guy" is even an insult.
- ZenoArrow 9y ago> "The phrase "wise guy" is even an insult." When wise guy is used as an insult, its meaning is close to that of smart arse, in that it implies someone is acting smart to belittle others. Whether that's the intention or not, that's what's being implied. If you take the ego boosting aspects out of it, then the term 'wise guy' is not derogatory. https://en.oxforddictionaries.com/definition/smart-arse https://en.oxforddictionaries.com/definition/smart-arse I'm aware of the irony of explaining this term in this way, but I can't think of another way to effectively do it.
- ranprieur 9y ago> we'll reach the limits of what our brains can grasp. But different brains are good at different things. There will never be a line where everyone can grasp everything on one side, and no one can grasp anything on the other. If one in ten brains can grasp something, there might still be academic departments that study it. But if only one in a thousand brains can grasp something, what do these people look like to the rest of us?
- jobigoud 9y agoWhat if the concept you need to grasp requires you to hold a extremely high number of "gateway" concepts simultaneously in your short term memory? There ought to be a limit at which point no humans can grasp the concept. And there would still be a lot of unexplored ideas on the other side.
- asimpletune 9y agoIt's kind of like the argument against trying understand the brain by modeling one: ok, so let's say you have a perfect model, all that's left is to understand your model. Or another way I've heard it explained. If we were trying to understand Mario and could perfectly emulate its circuit, would that translate into us understanding the concept of saving the princess? Probably not, we'd probably venture a guess that collecting coins is the most important thing in the game.
- csomar 9y agoI don't think Astronomy is easier than biology. It just happened that we were successful to calculate some stuff, but where we successful in say: Flying a rocket to Alpha Centauri. Curing common cold is not a calculation. Apples and Oranges. That being said, there is no limit to scientific understanding if we accept mathematical models (and maybe probabilistic ones). The trouble with the world is that we try to understand everything with our simple senses: feel of gravity, size, picture, touch, etc... Case in point, I was trying to explain to a friend that he should ditch the idea of a physical atom. An atom has no shape. It has volume and mass but that's it. It makes no sense to think that the nuclei is spheric or rectangular. At these scales, the geometrical reality is not a reality. But he still insisted that he wants to see what one "looks like". That's how we make sense of the world.
- analog31 9y agoShow him atomic force microscope images, or a single atom glowing in an atom trap. Show him how hypotheses about the shapes and sizes of nuclei are tested via atomic spectroscopy and scattering experiments.
- csomar 9y agoThat's quite some stuff I'm not aware of. I know that we know the shape of the atom by interacting with but I didn't know that we have that much precision at predicting a something more complex.
- MechEStudent 9y agoYes. The universe has a "Johari" window, that is an implication of Godel's incompleteness theorem.
- neuralzen 9y agoGlad someone mentioned this, it was the first thing that came to mind.
- ackfoo 9y agoMartin Rees is very inventive: he postulates limits to scientific understanding and immediately demonstrates them, using himself as the exemplar. Rees states, "Big things need not be complicated either. Despite its vastness, a star is fairly simple—its core is so hot that complex molecules get torn apart and no chemicals can exist, so what’s left is basically an amorphous gas of atomic nuclei and electrons." OK, Martin, in that case I expect your prediction for the exact number and distribution of sunspots on Sol for every day of 2018 on my desk in the morning. A star is fairly simple, no? So what's the holdup? Stars are complex; Martin Rees is simple.
- whatshisface 9y agoYour sunspot example is mostly determined by convection in Sol's outer layers, not the core. Stellar cores are usually in very tight equilibria.
- Houshalter 9y agoThe rules for air movement and and such are very simple, but no one can predict the weather more than a week ahead of time.
- dandare 9y agoI always wondered what if comprehensibility of physics is like a game of minesweeper - you solve a problem and you get clues that help you solve the next problem that gives you more clues. Sometimes you get stack and you have to continue on some other side of the maze that ultimately brings you back and helps you solve the stacked position. But sometimes the game of minesweeper is unsolvable, you are stack and the clues you got so fat are not enough and you will never get new clues. Can this happen in reality? I don't know. To make things worse, we will never be 100% sure that we didn't miss something, if we get stuck we will never be sure.
- jopsen 9y agoAnd sometimes you hit a mine, how like sometimes in physics you die from accidental radioactive poisoning :)
- oldandtired 9y agoThere are many interesting comments pro and con the the question. Over a recent period of time, I have had a good and thoughtful discussion with a nuclear physicists and educator about models in science. He did challenge me to look further into the subject, which I have. My statement to him was that "All models are wrong, but some are useful". Since that discussion, looking into mathematics , experimental evidence, various opposing theories about particular areas of science, I am now more in agreement with the statement "that all models are wrong, but some are useful". Our understanding of the universe around us is not only limited, but, we humans (all of us) get caught up in the dogmatic belief of our underlying premises. This works to limit our understanding about any area. The tools we use to do the investigation of the universe around us are just that tools. Whether we use machine learning and computers or space probes, telescopes, high energy colliders or electron microscopes, rulers and meters, these tools are only useful to the extent that we do not ignore the experimental results. In it very obvious that many (scientists) ignore questions that challenge their "pet" models. There are no stupid questions, just inappropriate answers. There is much data that has been collected that does not fit the standard consensus models and thinking. Whether or not an alternative model is useful, is not the problem here. It is the immediate response of anger that you should question the "dogma" that, in the end, limits our ability to further our understanding of the universe around us. I, personally, do not believe in major standard models in use today. I find that there are significant problems with those models in explaining the world around us and leave too many things ignored. Do I have an alternative model - No. But that's okay. I am not required to supply an alternative model, I just have to point out inconsistencies in the models and evidential data that is being ignored. Far too often, reputations are considered more important than inconsistencies. Consensus more important than problems in the models. If a question is raised that disputes a particular model and it cannot be answered simply then it might be a good idea to look for an alternative simpler explanation. There are ideas that are completely off the wall, but if investigated properly, we can discount appropriately and in that investigation we may find further areas for study that would not arise otherwise. Science should be fun.
- Manglano 9y agoTarski's undefinability theorem.
- EGreg 9y agoThere is a similar thing in mathematics. The Appel and Haken proof of the four color theorem was the first computer-aided proof of a major theorem. As such, we aren't sure why the theorem is true, but we are sure that it is. An interesting question is about the logical necessity of a mathematical theorem being true if we require a computer to interpret it. After all, we require people to interpret smaller logical statements, too! Stephen Wolfram'a "New Kind of Science" was all about that stuff. Did it ever reach any conclusions though? Or just "look how cool complexity can be?"
- pteredactyl 9y agoCan science answer what happens after death?
- acobster 9y ago"Science is not and cannot be a quest for a complete knowledge of the universe. Rather, it is a process whereby certain information is selected as being more relevant to human aims and understanding." - William Poundstone, from The Recursive Universe