• Georgios Bakalis
    17
    For some reason, I have only recently taken interest in formal (and sometimes informal) logic - I am a beginner. I am definitely not perfect, so I need help on this one thing I am trying to do. I am attempting to logically notate Darwin’s Doubt to work out if it is a valid inference, but also for practise.
    For those unaware, Darwin’s doubt was when Charles Darwin thought the following:
    If we evolved from primates, why should I believe that my thoughts are coherent and true, thus why would I believe we evolved?
    Others have tried to use this argument to ‘disprove’ determinism and claims such as ‘Nothing is true’. We might try to word this argument as: You cannot make a statement that undermines/disproves that very statement - at least, that is how I will think about it for the rest of this. You may object to Darwin’s doubt in many ways, but I am not currently concerned with that.

    I have logically notated it as follows:

    pT → ¬∃x xT, pT
    ∴ ¬pT

    ‘p’ represents any statement. ‘T’ represents ‘is true’. Under normal circumstances, pT does not ever imply that nothing is T, so this is perhaps already a massive flaw in my notation, but I’ll leave that up to you to decide.

    My biggest problem, though, is Stephen Meyer. He attempts to resolve Darwin’s Doubt by saying that intelligent design is the only explanation if evolution is true. This makes it more difficult for me to notate this.
    How would I write that? ‘r stops pT from implying ¬∃x xT’? It seems stupid, and I am sure that it is.

    I just need a bit of help.

    Edit: I have found out that ‘Darwin’s doubt’ is not the thing I have described in the above. So that I don’t have to rewrite a load of things, just keep this in mind.
  • unenlightened
    8.7k
    If we evolved from primates, why should I believe that my thoughts are coherent and trueGeorgios Bakalis

    The general answer to this is very simple. Thoughts that are not coherent and true would not on average aid survival. The planet is littered with the corpses of people who thought they could fly, or that they could live on fresh air alone, and so on. Realistic thinkers are favoured by natural selection. I know this because the Magic Beans told me in my sleep.
  • counterpunch
    1.6k
    If we evolved from primates, why should I believe that my thoughts are coherent and true, thus why would I believe we evolved?Georgios Bakalis

    Darwin should have taken a physics class or two; and perhaps he'd have paid more attention to the causal nature of the environment, that requires the organism must be physiologically and behaviourally correct to reality to survive. Natural selection is not just about eat or be eaten. Causality is a huge selection pressure. That so, he has no good reason to look down on our primate ancestors - and on that basis doubt the general veracity of his inherited faculties. We have survived thus far.
  • SophistiCat
    2.2k
    Edit: I have found out that ‘Darwin’s doubt’ is not the thing I have described in the above. So that I don’t have to rewrite a load of things, just keep this in mind.Georgios Bakalis

    "Darwin's doubt" is a nickname that Alvin Plantinga gave to the idea that you sketched in your post (in his book "Warrant and Proper Function"), although the idea itself goes further back. (It is doubtful that it accurately reflects Darwin's own thinking; in context, Darwin was musing about highly abstract theoretical constructs like moral theory and religion, not basic cognitive function.)

    Anyway, I don't think you will find answers to this question in formal logic: logic is not equipped to deal with epistemological issues like justification. You can, of course, formalize the thesis, but the result will be logically trivial, because all the non-trivial stuff will be encapsulated in the semantic content of logical symbols.

    If you want to pursue this particular question, you can start with the debate around Plantinga's thesis (and you will quickly find that it leads deeper into the epistemological weeds - theories of justification, epiphenominalism, etc.)


    What I found interesting about your stab at formalization is what should at first strike one as a basic error: You write pT to express that p is true. That is not how one would usually notate that in logic. In a logical formula when you write a symbol for a proposition, its truth is implicit (to express falsity you would use negation). But I think this notational error is telling: you are trying to express general theses about truth or consistency of an entire system. This will take you into very different weeds than what I referred to above - the metatheoretical work on formal languages and logic that goes back to Tarski and Godel. They won't help you with your epistemological query, but you may find them interesting in their own right.
  • ernest meyer
    100
    Causality is a huge selection pressure.counterpunch

    That's funny, I woke up this morning thinking Trumpism might be a brain dysfunction, rendering the individual incapable of performing simple truth evaluation of standard causal relationships if they conflict with hedonist desires.

    Maybe the dysfunction has even proven to be the fittest solution to the last moments of survival on a doomed planet, as the authority structure in the human race's most powerful social organization on the planet has not evolved to the point of consistent rational response to the threat of global warming.

    My favorite remains Trump's modification of a USGS weather map with a black felt marker he is holding in his hand while 'proving' a storm should reach Georgia as he claimed, and the USGS had already repeatedly denied. If only such acts really had been intended as a joke, he would have been one of the greatest comedians ever.
  • ernest meyer
    100
    My biggest problem, though, is Stephen Meyer. He attempts to resolve Darwin’s Doubt by saying that intelligent design is the only explanation if evolution is true. This makes it more difficult for me to notate this.
    How would I write that?
    Georgios Bakalis

    [url=http://]https://en.wikipedia.org/wiki/If_and_only_if[/url]

    While it might seem an outlandish proposition, it does have the benefit over current natural selection theory of actually being falsifiable, as it does not admit to 'unknown selection force.'
  • counterpunch
    1.6k


    That's funny, I woke up this morning thinking Trumpism might be a brain dysfunction, rendering the individual incapable of performing simple truth evaluation of standard causal relationships. Maybe the dysfunction has even proven to be the fittest solution to the last moments of survival on a doomed planet, as the authority structure in the human race's most powerful social organization on the planet has not evolved to the point of consistent rational response to the threat of global warmingernest meyer

    Climate change was first brought to the President's attention in the 1950's. Eisenhower was the first President briefed on climate change. Scientists knew a lot less back then - than they do now. Climate change began as an explanation of the surface temperature of Venus, which is hotter than Mercury, while much further from the sun. The thick atmosphere traps heat - and it was soon realised, we are thickening our atmosphere too, and even small temperature rises would have big consequences.

    It didn't begin with Trump - but worse than this, it won't end with Biden. He's intending to spend about $2 trillion on the wrong technologies, and the wrong approach to climate change. All this wind and solar, pay more have less, stop this, tax that - eeking out our existence forever after won't work.

    We need to drill for magma energy on a huge scale. Tap into the virtually limitless heat energy of the big ball of molten rock beneath our feet, and spend that energy prodigiously - to meet our energy needs cleanly, to extract atmospheric carbon and bury it, desalinate water to irrigate land, produce hydrogen fuel, and recycle, while the man on the street carries on - very much as he is.

    And here's the thing; given the economic case for magma energy - the right might be convinced of this - but the left are way too certain of their own righteousness. Elements of the left want to undermine capitalism and exercise the authoritarian political control necessary to a "limits to resources" approach. But they're wrong. Malthus was wrong. In fact, resources are a function of the energy available to create them.
  • ernest meyer
    100
    Yes, Im still thinking about that. As of the current state of affairs, the left and the right have 'evolved' into purely combative positions that don't even act in their own self interest. If the left had impeached Trump for violating his oath of office and not protecting the life of Pence, instead only calling to find out if he had changed his mind about election certification before Pence escaped, there would have been no logical possibility of him beating the impeachment. But the left chose to impeach him for starting an insurrection, again making dubious claims of unprovable immorality. What I currently find of note is the number of criticisms that can now be made of the US government, parties aside, that it previously made of the USSR in the 1970s:
    * The largest wealth disparity ever
    * Biased news propaganda
    * Six times more military spending than any other nation
    * 'Tactical nuclear bomb' development sidestepping nuclear treaties
    * Governmental incompetence, including, being unable to remove the President from opffice.
    * Forest fires with smoke so thick for hundreds of miles you can't see more than 100 yards for a month.
    * School illiteracy, widespread ignorance, riots, and gun murders
    * Homelessness, alcoholism, wife abuse, runaway teens, and opiate addiction
    * Labor exploitation without unions being able to protect worker rights
    * Highest incarceration rate of any country ever
    * Human rights violations up to and including torture
    * This year, four trillion dollars of pork-barrel spending without any compromise.
    * And most recently, the Supreme Court just indicated that there would be no problem with approving Trump getting back on Twitter, saying it was a violation of free speech to ban him...so, the President has licensed freedom to say anything he wants.

    the only signficant difference between the USA now, and the USSR as it was in the 1970s, is that it has two parties exercising decadence without check instead of one, to little apparent benefit. Thus partisan differences of opinion are really no longer the issue. Now we are confronted with the time delay of an issue reaching the point where it can be taken seriously enough to warrant ANY political action. For slow moving problems like global warming, the USA appears incapable of taking any effective action at all. Consider, its last Supreme Court decision on gun control permitted limited use of some firearms in self defense, without defining the limits or which firearms, in 2008. Since then, the USA has had more firearm fatalities than died in WW2, which was the justification for trillions of spending against COVID this year. Yet despite repeated attempts at gun control since 2008, special interest groups have fought firearm limitations in court so much that gun deaths are still going up. Global warming is a similar issue to guns, and the outlook is bleak.
  • counterpunch
    1.6k
    So that's why Trump wanted to build a wall - to stop people getting out? Like the USSR did!
  • ernest meyer
    100
    Well the USSR had the opposite problem to the USA in the 1970s. The USA used to be in growth mode and has been trying to reverse long-standing social protocols, such as turning a blind eye to illegal immigration so that illegal immigrants could work on farms at sub-minimum wages. The USSR in the 1970s was still recovering from its massive loss of life in WW2, and still has a relatively low population, although not to the drastic level of underpopulation it has for the first three generations after WW2. So its reward to women having more than 10 children, a vacation in Moscow with a medal award for service to the nation, was lowered to 8 children, then discontinued.
  • counterpunch
    1.6k
    I'm learning so much from you. I had no idea that people fled the USSR because of underpopulation. Weird though, how they still had such long queues for bread! Russians must bake great bread!
  • fishfry
    2.6k
    That's funny, I woke up this morning thinking Trumpism might be a brain dysfunctionernest meyer

    No longer lives in the White House but still lives rent-free in your head.
  • ernest meyer
    100
    yes, that's right. In an industrial economy, a sudden decrease in population results in lack of commodities, depressed wages, lower education standards, and all the many other disadvantages that led to the end of massacring peasants in feudal wars, although it did take several thousand years of human civilization to figure that out, so empirically, its something you actually have to learn by studying it. https://en.wikipedia.org/wiki/World_War_II_casualties_of_the_Soviet_Union
  • counterpunch
    1.6k
    In a capitalist economy, one might imagine, underpopulation would lead to increased wages, technological innovation, and so higher educational standards - as people seek even better wages by gaining technological skills. If only we didn't need every peasant out there buying ugg boots and iphones!
  • ernest meyer
    100
    well no, thats not what happens, because most simply put, EMPLOYERS DONT HAVE AS MUCH INCOME TO HAND OUT, which was a severe and catastrophic effect in a tabu period in US history after the civil war, the only periopd in US history even closely comparable to the USSR. It's not taught much in schools, and the information on it is pretty dicey, because another effect is rampant inflation, which disguises the effects of losses to individuals if you wish to be a deviant economist, and inflation wasnt understood at all at the time, but you can see about it if you look up 'long depression' on the Web, during which, wages first plummeted due to increased workforce size from setting slaves free, tens of thousands of businesses and farms foreclosed from lack of income, then almost all the banks went bankrupt, almost everyone lost all their savings, and millions starved to death. Even the exact duration of the 'depression' varies where you see about it, and due to inflation not being understood, it wasn't obvious why so many people were suffering from not having money. But it wasnt as bad as the loss to russia of its new industrial workforce, and only lasted one or two generations instead of three or four. It's really a horrible subject and if you excuse me Im going for a walk. Have a nice day )
  • ernest meyer
    100
    its a very popular delusion that Trump is gone. He and his tribe are only in recess. Last week, Judge Thomas said he is oipen to arguments that banning Trump from Twitter was a violation of free speech, and as he is in a GOP-majority supreme court, it means his tweets are coming back, like it or not, whether he or one of his tribe run, he's coming back. And probably will win. He came a lot closer to winning after his covid denial than I expected, but if not, I really dont want to be here for the next round of riots. Come to Europe ) lol. Im going for a walk, later.
  • fishfry
    2.6k
    its a very popular delusion that Trump is gone. He and his tribe are only in recess. Last week, Judge Thomas said he is oipen to arguments that banning Trump from Twitter was a violation of free speech, and as he is in a GOP-majority supreme court, it means his tweets are coming back, like it or not, whether he or one of his tribe run, he's coming back. And probably will win. He came a lot closer to winning after his covid denial than I expected, but if not, I really dont want to be here for the next round of riots. Come to Europe ) lol. Im going for a walk, later.ernest meyer

    Make sure you obsess about him night and day. And never ever spend a moment reflecting on the conditions and factors that led to his unlikely rise, and that are still present in the body politic. Such as the endless wars, the corrupt global elite, the deliberate hollowing out of the heartland, the wholesale selling off of the productive capacity of the country to China. None of that matters. Only your obsession with the Orange Man matters. Never think any deeper than Orange Man Bad and you'll be fine. And remember, "Trump put kids in cages." Whereas Joe Biden puts kids in cozy relocation facilities. So the left no longer cares. Some of us independent-minded types see the hypocrisy, especially since those of us who closely follow border politics know that Obama and Biden were the ones who originally built the cages. That's why millions who voted for Obama twice, voted for Trump in 2016. Because they suddenly became racists? Keep believing that and the next Trump will have a smoother personality and won't be such a self-destructive 3AM tweeter.

    Take my advice and try to see Trump in a larger context. In a functioning system, Trump never could have gotten anywhere near the presidency.

    Come to Europeernest meyer

    Europe is a disaster. The project is failing.

    But just to keep this on topic, I would like to note that there was another Darwin thread the other day that attracted scant attention at https://thephilosophyforum.com/discussion/10653/evolution-as-partial-explanation-from-darwins-greatest-foe-george-mivart

    I've been watching a lot of ID and anti-Darwin videos lately and I find the subject interesting, so I'd welcome informed (or uninformed, as the case may be) commentary and discussion. And less gratuitous drive-by pot shots at politicians. After all if I walked into my doctor's office and presented the way Joe Biden does, my doc would offer me a cognitive assessment. The president of the United States isn't all there and everyone knows it. Putin and Xi are watching this, and all some people can do is hold on to their anti-Trump feelings. Tell me how this ends well. Kamala was put in charge of the border two weeks ago. She hasn't deigned to visit the border, but staged a photo-op eating a piece of cake at a black-owned bakery. Asked about it, bad liar Jen Psaki said, "She's entitled to a snack."

    Is that the best you can do as an antidote to Trump? I don't see much improvement in the running of our government, just a lurch in a different direction.
  • T Clark
    13k


    It is extremely inconsiderate to shanghai someone's thread for a completely unrelated subject. You should stop.
  • T Clark
    13k


    You should stop this. @Georgios Bakalis is new here and you're stealing his thread.
  • Wayfarer
    20.7k
    Thoughts that are not coherent and true would not on average aid survival.unenlightened

    The argument is about evaluating truth statements. Every surviving species, other than h. sapiens, manages to survive and procreate without any such ability whatever. Only a sentient being with the ability to think and speak is even able to contemplate such a question. So to ascribe 'survival value' to the content of propositional belief, is to judge it by a criteria other than reason; in other words, it's no longer a matter of rational judgement. 'The only form that genuine reasoning can take consists in seeing the validity of the arguments, in virtue of what they say. As soon as one tries to step outside of such thoughts, one loses contact with their true content', says Thomas Nagel. And evaluating them from the perspective of biological adaption is exactly that. And this is precisely the way that Darwinian thinking does devalue rationality; it has nothing to do with arguments over the creation of species, as such, but it's because it's where a biological theory starts to masquerade as a normative philosophy, which it isn't.

    If we evolved from primates, why should I believe that my thoughts are coherent and true, thus why would I believe we evolved?Georgios Bakalis

    Because we evolved to the point where we could reason, think, and understand logical and mathematical principles. At the point where those abilities become manifest, sometime in the last 100k years, then new horizons become perceptible that were not available to our simian forbears. That doesn't require doubting the narrative history of evolution, but it might require re-thinking the conclusions that are often made on that basis.
  • Tom Storm
    8.4k
    Because we evolved to the point where we could reason, think, and understand logical and mathematical principles. At the point where those abilities become manifest, sometime in the last 100k years, then new horizons become perceptible that were not available to our simian forbears. That doesn't require doubting the narrative history of evolution, but it might require re-thinking the conclusions that are often made on that basis.Wayfarer

    Nicely phrased. Are you able to provide an example of such a re-thought conclusion?
  • counterpunch
    1.6k
    You should stop this. Georgios Bakalis is new here and you're stealing his thread.T Clark

    Well okay then, but my original comments were about Darwin's Doubt - a concept Georgios raised, but doesn't actually want to discuss. He just wants to know how to do the logical notation - while sticking it to my hero, and favourite scientific theory of all time! Admittedly, wandered off a bit after that, and I will stop - but Darwin's Doubt should be open to discussion as it was raised in the OP!
  • Wayfarer
    20.7k
    Nicely phrased. Are you able to provide an example of such a re-thought conclusion?Tom Storm

    I would recommend Thomas Nagel's essay Evolutionary Naturalism and the Fear of Religion as a good starting point (.pdf shared via Google Drive).
  • Tom Storm
    8.4k
    Ta. I'm not keen on the overuse of evolutionary biology to explain all things either.
  • Tom Storm
    8.4k
    With Nagel you get the sense he's poised just short of a religious conversion. Having a brief look at his work from an ignorant layman's perspective, there seems to touch of Alvin Plantinga in his oeuvre. E.g., How do we explain the emergence of the logical absolutes in a naturalistic world? Presuppositionalist apologetics uses this, with the additional idea that atheism is self refuting. Do you think Nagel's understanding of science is sufficiently robust to justify the critique he is using? He talks about the fear of religion and the idea of God, ok, but it is also certainly the case that people palpably fear science and Darwinism too and not just those folks in small Southern towns who like juggling snakes.
  • ernest meyer
    100
    The argument is about evaluating truth statements. Every surviving species, other than h. sapiens, manages to survive and procreate without any such ability whatever. Only a sentient being with the ability to think and speak is even able to contemplate such a question.Wayfarer

    With regrets, I have to object that the actual process going through the brain of an animal species is largely beyond our comprehension. There are some specific examples of animals demonstrating complex reasoning tasks. For example, I have seen demonstrations of crows figuring out sequences of half a dozen levers to push and weights to move in a particular sequence, in order to obtain food. I have seen chimpanzees demonstrate knowledge of object permanence. And I have seen dolphins show they can distinguish between rounded shapes and shapes with corners. These demonstrations show that animals can form ordered, rational deductions from abstracted principles. Therefore, there must be SOME mechanism inside their brains which is able to evaluate at least a subset of logical propositions, as we know them, and we can't actually know if the animal is aware of the cognition, or if it happens in the same automatic way as electricity flows through a circuit when a battery is attached to it.

    With reference to above on Tom Nagel, there is also his famous paper 'what's it like to be a bat?'

    https://www.sas.upenn.edu/~cavitch/pdf-library/Nagel_Bat.pdf

    And what is the significance of that to the OP, well I think it is a general criticism of the evolutionary debate that it focuses on God versus automatic processes, which I had posted yesterday and had thought the posters had read and started a new thread, but if not:

    First, if God is more intelligent than we were 5,000 years ago, then God uses tools. Using natural selection to do most the work, while tweaking a DNA pair here and there would be a natural thing for an intelligent creator to do.

    Second,making the argument solely about natural selection versus traditional concepts of God ignores the presence of other possible teleological forces. An animal might simply have a sense of beauty, and prefer the appearance of one animal over another because of that. I understand some would say such teleological processes are themselves product of natural selection. But that defeats the point of the scientific model of evolution in the first place, which was, to provide as simple a model as possible to explain observed species variation. Once one starts annexing suppositions as to causality to the Darwinist theory, or suppositions of what animals actually think, then it is no longer a scientific theory. Now one might prefer to make metaphysical statements, rather than construct a scientific model, but in that case, the conventions of science no longer apply to the conclusions. Most of the errors here noted, and most subjects of evolutionary debate, arise from attempts to extend a scientific model of natural selection to include causal explanations that are emprically untestable, and therefore, not scientific.
  • Wayfarer
    20.7k
    I too think that Nagel might ultimately convert, but elsewhere he states plainly that he has no 'sensus divinatus'. That essay is really a precursor to his 2012 book, Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature is Almost Certainly False. (I'm sure the publisher added the subtitle.) There was a lot of controversy around that book and it's been discussed here quite a bit. Suffice to say I'm on the side of Nagel against his critics, and the fact that he's not writing from a professedly religious conviction I think counts in his favour.

    How do we explain the emergence of the logical absolutes in a naturalistic world?Tom Storm

    I think that logical absolutes don't emerge but that humans evolve the capacity to grasp them. Whereas nowadays, it is almost universally accepted that reason, math, etc are an evolved capacity, and so can be 'explained' in terms of biological adaptation - which is the essence of biological reductionism. I hope you can see the irrationality of that idea. And that you see how this links back to mathematical Platonism, and why on that account platonist realism about maths is nearly universally rejected. (None of what I'm saying is argued on the basis of any kind of creationism or intelligent design but purely on philosophical grounds.)

    Again, Darwinism is a theory about the evolution of species. Yet it has become much more than that, it is assumed to provide an explanatory background for the whole of human nature, a 'theory of everything' when it comes to life. But Darwin himself was no philosopher, so much as a product of the Scottish Enlightenment (along with David Hume, Adam Smith, and others) and the only principle it entails is that of reproductive sucess and adaption to the environment. Yet now all philosophy is subordinated to it, as if it is the supreme explanatory principle.

    Most of the errors here noted, and most subjects of evolutionary debate, arise from attempts to extend a scientific model of natural selection to include causal explanations that are emprically untestable, and therefore, not scientific.ernest meyer

    I would say that they arise from the extension of methodological naturalism to a metaphysical principle.
  • ernest meyer
    100
    I would say that they arise from the extension of methodological naturalism to a metaphysical principle.Wayfarer

    well yes, I'd have ot think how much methodological naturalism varies from a scientific method, I would guess the second is similar but extends to a larger scope.
  • Tom Storm
    8.4k
    . But Darwin himself was no philosopher, so much as a product of the Scottish Enlightenment (along with David Hume, Adam Smith, and others) and the only principle it entails is that of reproductive sucess and adaption to the environment. Yet now all philosophy is subordinated to it, as if it is the supreme explanatory principle.Wayfarer

    I hear you but surely Darwinism has also 'evolved' and the understandings that come out of it are much more complex and nuanced than some critics may allow.

    I am not qualified to say where Darwinism might lead us. But I do know that people like Daniel Dennett and Richard Dawkins probably trigger more fear and contempt than any other thinkers around. That on itself is worth an essay similar to Nagel's. David Bentley Hart on Dennett's 'rather silly' theories of consciousness are a vituperative treat to read. And yet it is also argued by Dennett and some of his defenders that people like Bentley Hart misinterpret and provide reductive accounts of Dennett's ideas. Everyone seems to have decided that the other party is reductive and holds inconsistent beliefs.
  • counterpunch
    1.6k
    Could you tell me what religion you are? I want to trash it to prop up my own beliefs!
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