The Problem of Predictive Equivalence

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In the previous section I described the argument that many biologists have endorsed for thinking that the hypothesis of evolution by natural selection is more likely than the hypothesis of intelligent design. This argument considers the observation that organisms are often imperfectly adapted to their environments and construes the design hypothesis as predicting that organisms should be perfectly adapted. This version of the design hypothesis presupposes a very definite picture of what God would be like if he existed.

Actually, in the previous section Sober was primarily concerned with creationism. This is made rather obvious by the chapter title. It’s as if he was writing about Creationism and then Intelligent Design burst on the scene and he had to change things up to make it appear as if the two are the same. But what’s a philosopher of biology to do?

The point here is to demonstrate how evolutionary arguments are in fact theological rather than scientific. This is admitted by a major philosopher of biology. This OP was motivated at least in part by claims by Rumraket that the genetic code ought to be perfect if it was designed. Arguing that it’s not perfect, therefore it’s not designed. To quote Sober, “This version of the design hypothesis presupposes a very definite picture of what God would be like if he existed.”

What does this have to do with actual science, if anything?

Why do biologists (and Rumrakians) require the foil of a perfect designer God in order to make their case for evolution?

What reason do we have to believe that an intelligent designer would ensure that her organisms were perfectly adapted to their environment?

What reason do we have to believe that natural selection leads to organisms that are imperfectly adapted to their environment?

196 thoughts on “The Problem of Predictive Equivalence”

  1. keiths:
    Flint,

    No, the word ‘variation’ can be used either to refer to a process or to the result of that process.The same is true for ‘mutation’.

    Variation (the process) produces variations (the result), and mutation (the process) produces mutations (the result).And since mutations are a form of variation, we can say that mutation (the process) produces variations (the result).

    Note, however, we that we don’t use the plural when referring to the process.So this statement of yours…

    …is incorrect.Mutations are themselves variations.They don’t cause variation (the process)*; they’re the result of it.They don’t cause variations — they are variations.

    So my original statement is correct, and your revision of it is not.

    OK, I get it. Variation is what causes variations. Color (also a verb or a noun) is what causes color. Size is what causes size. Who knew? I had always thought that variations were introduced into a population through a mutation process, which could include inexact copying, sexual recombination, cosmic rays, etc.

    But since this is apparently incorrect, it leaves one wondering whether variation being its own cause is circular. Now that I understand that evolution is the cause of evolution, all my questions are set to rest forever.

  2. Flint,

    OK, I get it. Variation is what causes variations.

    Or as I put it above, variation (the process) produces variations (the result).

    Color (also a verb or a noun) is what causes color.

    No. We’d use the word “coloring” to designate the process (or “colorization” if we were talking about movies). Coloring (the process) gives an Easter egg its color (the result).

    Size is what causes size.

    Again, no. We’d use the word “sizing” to designate the process in this case. For example, “The carpenter sized the bookcase to fit between the piano and the wall.” The sizing is what produced the specific size of the bookcase.

    I had always thought that variations were introduced into a population through a mutation process, which could include inexact copying, sexual recombination, cosmic rays, etc.

    They are. As I said:

    And since mutations are a form of variation, we can say that mutation (the process) produces variations (the result).

    Flint:

    …it leaves one wondering whether variation being its own cause is circular.

    No, because variation (the process) is distinct from the resulting variations, as I’ve already explained.

    Now that I understand that evolution is the cause of evolution, all my questions are set to rest forever.

    They shouldn’t be. You’ve badly misunderstood the issue if you think that using the same word to designate a process and its results amounts to a science-stopper.

    Linguistic and grammatical analyses require attention to detail, Flint. The reasoning in your comment was slapdash. Slow down and think things through.

  3. keiths: Linguistic and grammatical analysis require attention to detail, Flint, but the reasoning in your comment was slapdash.Slow down and think things through.

    My concern is with the mechanisms at work in the process. I was mocking your need to be right at all costs, even if you must descend to linguistic acrobatics.

    Using the same word to designate a process and the result of that process might be linguistically allowable, but it’s guaranteed to cause confusion. Despite this you are, as always, absolutely correct. Which you don’t need me to tell you.

  4. Just for the fun of beating this dead horse into the ground, consider the equivocation creationists use between Design as a process, and Design as the result of that process. The crux of their argument is that we observe Design (the noun) and we infer Design (the verb). The more intelligent the Design (noun) appears to us, the more intelligent the Design (the verb) must have been. How could it be otherwise?

    Whole books have been written switching interchangeably back and forth between the two

  5. Flint,

    I was mocking your need to be right at all costs…

    I don’t have that need. It doesn’t bother me to admit errors, as I’ve explained (and demonstrated) in other threads at TSZ. But I certainly won’t pretend to be wrong just to mollify an insecure hothead like you. That would be dishonest and counterproductive.

    …even if you must descend to linguistic acrobatics.

    I haven’t done so. The use of ‘variation’ to designate a process is perfectly standard in English (and in biology), and so is the use of ‘variation’ to designate the result of such a process. Aren’t you a native speaker?

    Usage examples are extremely easy to find. For example:

    ‘Variation’ as a process:

    In particular, the way in which facilitated variation produces phenotypic variants has three crucial implications for evolution…

    And in the very next paragraph, ‘variation’ is used to designate a result rather than a process:

    One of the most important contributions of robustness is that of storing up genetic variation as a resource for future adaptive phenotypic responses. A vivid, but by no means unique, example is found in the heat shock protein. HSP 90 acts as a capacitor for evolution, by damping down phenotypic variation and allowing genetic variation to accumulate.

    Flint:

    Using the same word to designate a process and the result of that process might be linguistically allowable, but it’s guaranteed to cause confusion.

    First, note that I did not repeat the word twice in the question you originally objected to, which was directed at Alan:

    How can you not understand that variation is what generates the positive mutations that selection favors?

    There was no good reason for you to object to my phrasing, and the reason you gave made no sense, as I’ve explained.

    Second, note that when I did repeat the word twice in a sentence, as I did here…

    Variation (the process) produces variations (the result),

    …I did so precisely to demonstrate that the word could fulfill distinct roles, which is the point you were missing, leading to your confusion.

    Despite this you are, as always, absolutely correct. Which you don’t need me to tell you.

    You made an error, and I correctly pointed it out. You dug in your heels and made more errors, which I also correctly pointed out. Why are you angry at me? The mistakes were yours, not mine.

    Your childishness has made this exchange unpleasant. Try to do better next time.

  6. keiths: don’t have that need. It doesn’t bother me to admit errors, as I’ve explained (and demonstrated) in other threads at TSZ.

    Link please

  8. keiths: Your childishness has made this exchange unpleasant

    I think you meant to say “my unpleasantness has made this exchange childish”.

    At the risk of getting tangled up with the tar baby, the confusion that Keiths is appearing to create is that mutations are one example of variation. Variation is the general term for what is grist to the mill of selection. Mutations are an example of variation that can be conserved or removed by selection. (And some mutation, notably substitution of the third nucleotide for any other where redundancy in the triplet code means no change in the translated amino-acid – glycine, alanine, valine – is silent.)

    The chromosomes, or rather the DNA sequences within them, are the heritable material that result in variation in phenotypes (selection acts on the whole organism) which results in adaptive evolution. Variation in DNA sequences (alleles – differing copies of genes is the result of copying errors (mutations) and mutations can be induced by damage to chromosomes caused by radiation and mutagens but an important source of variation in sexually reproducing diploids is meiosis, gamete formation and fusing into the zygote. Not only does the offspring inherit a selection of half the genes of two parents, but recombination during meiosis provides mixing which increases the variation available for selection to work on.

  9. Alan,

    There’s a lot of verbiage there, but what’s missing is a defense of your claim.

    I wrote:

    Right. So one way to fix Neil’s statement is to change it from this…

    Darwinism is only “eliminate the negative”. That’s not enough. You also need “accentuate the positive”.

    …to something like this:

    Selection by itself only eliminates the (relatively) negative. That’s not enough. You also need to generate the positive, which is where variation comes in.

    Variation is what generates the positive. Natural selection accentuates the positive by selectively eliminating the negative. That’s Darwinian evolution.

    It makes perfect sense. Neil’s objection is bogus.

    You took issue with this sentence…

    Variation is what generates the positive.

    …and commented:

    Nonsense. Variation is random.

    Flint quickly pointed out your mistake:

    Why can’t random variation sometimes generate an improvement?

    You even undermined yourself by agreeing with his point:

    It often does.

    But if random variation does sometimes generate improvements — and it obviously does — then my statement is correct:

    Variation is what generates the positive.

    …and your objection is inane and off base:

    Nonsense. Variation is random.

    As if variation, being random, could never produce anything beneficial! That’s the kind of stupid argument you’d expect to get from an IDer, not an evolution supporter.

    Do you see your mistake? It’s a doozy.

  10. newton: I am still pondering how one uses a screwdriver as a sex toy.

    Carefully ,I guess

    The metal rod is now the handle, and what used to be the handle is for the requisite orifice. I didn’t come up with this.

  12. Rumraket: The metal rod is now the handle, and what used to be the handle is for the requisite orifice. I didn’t come up with this.

    Is that a screwdriver in your pocket or are you just happy to see me?

  13. Flint:
    Just for the fun of beating this dead horse into the ground, consider the equivocation creationists use between Design as a process, and Design as the result of that process. The crux of their argument is that we observe Design (the noun) and we infer Design (the verb). The more intelligent the Design (noun) appears to us, the more intelligent the Design (the verb) must have been. How could it be otherwise?

    Whole books have been written switching interchangeably back and forth between the two

    Serendipitously, just before I read your exchange with keiths I was reading the following passage from Owen Barfield in his book “Romanticism Comes of Age” where he discusses the philosophy of Samuel Taylor Coleridge:

    I said that in his logic one feels the presence of of the logos. Some of the most startling, I will say sublimest, passages in his Treatise on Logic are concerned with grammar, generally, with language. I can only give a few extracts. Thus, he points out how the world of grammar subsists between the two poles of verb and noun, the one expressing activity and the other passivity, the one an action and the other a state. All the parts of speech may be so to speak polarized into these two components with one of them predominating. We may think of grammar as a sort of world revolving about an axis. Only in the axis itself do the two poles coincide. And what is this axis? It is the verb ‘to be’ itself. This verb ‘to be’ is the only word which expresses both action and state. Only ‘I am’ is both verb and state at the same time.

    ………… I am………
    ……………..|…………
    …………./…….\………
    …….Noun………Verb…..

    I spoke just now of the wholeness of Coleridge’s system of thought. I justness of this expression will become clearer as we go on to see how the second of the two essential elements in that system arises inevitably out of the first; how the law of polarity is already implicit in the conception of Reason as Productive Unity.

    In Coleridge’s words ‘the essential duality of Nature arises out of its productive unity’ Unity which is productive must strive to do two things. It must strive to reproduce itself, that is it must strive to to detach from itself another being like itself and in the same act and moment it must strive to overcome that detachment, to overcome that individuation, thus maintaining the unity.

    This is the first polarity, the polarity which underlies all life. And it is because it is based so firmly on this foundation that Coleridge’s system of thought may itself be called living, organic. He himself contrasts it with the so-called ‘philosophy’ which was fashionable in his time and which with some unimportant trimmings is still fashionable in our own-the Atomic philosophy. Coleridge calls the latter a ‘mechanic system’ and insists that its knowledge is limited to distance and nearness, in short, to ‘the relation of unproductive particles to each other.’ This, he says, is the philosophy of death. It holds good only of dead nature. Whereas all life consists in the strife of opposites.

    (I tried to show the diagram as it appears in the book, I hope it works.)

  14. keiths:
    Alan,
    There’s a lot of verbiage there, but what’s missing is a defense of your claim.

    My claim being the remark “nonsense” to “Variation is what generates the positive.” Right? I presume you agree that “variation is random”.

    Variation is what generates the positive. Natural selection accentuates the positive by selectively eliminating the negative. That’s Darwinian evolution.<

    Didn’t make perfect sense to me when I read it and the first sentence implies that “variation” by producing “positive” new material has some hand in whether it is beneficial or deleterious. Whereas in fact variation is a random process.

    Variation is the source of all new combinations of genes and new mutations. There is no way to test other than by letting selection decide to, then, with hindsight, attribute “beneficial”, “neutral” or “deleterious” to a particular DNA sequence. As Flint remarks “Variation proposes; selection disposes.”

    Flint quickly pointed out your mistake. You even undermined yourself by agreeing with his point

    Flint queried. I clarified. I repeat Variation is the source of all new genetic combinations and the decision whether such new combinations are beneficial or not only emerges in the light of selection.

    But if random variation does sometimes generate improvements — and it obviously does — then my statement is correct.

    I’m not disputing that. See above. My first mistake was to be too brief and my second is that I wrote too much verbiage.

    As if variation, being random, could never produce anything beneficial!

    Now that is misrepresentation again. Variation is the source of new genetic material. It only becomes beneficial if positively selected. The peppered moth variants, dark and light, can only be considered to carry beneficial traits if the niche favours such traits. Where the niche has more dark roosting spots, the dark variant has beneficial genes. In a niche with more light roosting spots, the same gene-set is deleterious.

    Variation is random.

    If I misinterpreted or was ungenerous in reading the remark of yours I labelled “Nonsense”, then I apologise.

  15. keiths:
    newton,

    See this and this.

    That entire comment thread is fascinating and revealing:

    These are links to you admitting mistakes? Perhaps I got the wrong link. Could you copy and paste the part where you are admitting a specific mistake? It appears vague.

    Actually I can’t find it at all.

  16. Alan Fox: Now that is misrepresentation again. Variation is the source of new genetic material. It only becomes beneficial if positively selected.

    That’s backward. It is positively selected only if it is beneficial, other things being equal.

    Glen Davidson

  17. GlenDavidson: That’s backward.It is positively selected only if it is beneficial, other things being equal.

    Glen Davidson

    OK; but the same genes can be beneficial or deleterious depending on the particular niche. Hence my reference to peppered moths.

  19. CharlieM,

    From the same book Barfield continues:

    To have revealed the law of polarity as the process which underlies all life and then to be able to educe this law of polarity from productive unity, i.e. for instance, in treating that are have come into being. The connection between these two aspects of the Logos is not an easy one to see. We may get glimpses of it in art and poetry. The aim of this building and of the work that is carried out in it is sure to make that very connection clearer to the world. I only want to indicate in a very sketchy way how Coleridge strove to grasp in thought both these aspects of the Logos as well as the connection between them.

    For instance, in treating of language, he points out how on the one hand the letters or sounds provide the elements of sameness (for the same letters must be used over and over again) while the positions of these letters (which are almost infinitely variable) provide the counter-element, or counter-pole, of difference. Sameness and Difference are the positive and negative aspects of what? Of likeness

    This was written before there was any proposal that DNA was involved in development and evolution. Had it been written now I’m sure Barfield would have seen this law of polarity between the letters and words of the alphabet as being relevant also to DNA, , or more precisely, amino acids, and the proteins that arise therefrom, difference coming out of sameness.

  21. Alan,

    Now that is misrepresentation again. Variation is the source of new genetic material. It only becomes beneficial if positively selected.

    That’s completely backwards, as Glen pointed out.

    Jesus, Alan. In your desperation to find something in what I wrote — anything — that you can label as a mistake or a misrepresentation, you’ve shot yourself in the foot again.

  22. keiths:
    Alan,

    That’s completely backwards, as Glen pointed out.

    He did and he added

    It is positively selected only if it is beneficial, other things being equal.

    And I wonder what “all things being equal” means as the same genes can be either beneficial or deleterious depending on the niche.

    Jesus, Alan. In your desperation to find something in what I wrote — anything — that you can label as a mistake or a misrepresentation, you’ve shot yourself in the foot again.

    You’re the guy obsessed with mistakes.

  23. newton: Link please

    It doesn’t bother keiths to say that it doesn’t bother him to admit errors. I’ll vouch for him on that.

  24. Alan Fox: Variation is random.

    And the ‘niche’ isn’t?

    Do you really think that ‘the niche’ gives a flying rat’s ass if changes to ‘the niche’ benefit the organism’s that inhabit ‘the niche’ in any way (or not)?

    Changes to ‘the niche’ would therefore appear to be random in the same sense that mutation/variation is said to be random.

    Wouldn’t you agree?

  25. Mung: And the ‘niche’ isn’t?

    Not in its effects, no. Effects can be non-random without needing an “Intelligent” agent.

    Do you really think that ‘the niche’ gives a flying rat’s ass if changes to ‘the niche’ benefit the organism’s that inhabit ‘the niche’ in any way (or not)?

    Nope. What have I written that makes you think so?

    Changes to ‘the niche’ would therefore appear to be random in the same sense that mutation/variation is said to be random.

    Niches can and do change and those changes aren’t necessarily predictable. I hope that the worst predictions on climate change are wrong.

    Wouldn’t you agree?/blockquote>With?

  26. Alan Fox: Niches can and do change and those changes aren’t necessarily predictable. I hope that the worst predictions on climate change are wrong.

    I didn’t say anything about predictability. You were going on about how variation is random. Did you just meant to say that variation is unpredictable?

  27. walto: Mung, is there any chance you could provide a citation to the excerpt you’re quoting from…and a link?

    It’s from Sober’s Philosophy of Biology, Second Edition.

    iirc:Chapter 2 Creationism. Section 2.6. I’ll confirm this later today.

  28. Kantian Naturalist: Creationism has very definite entailments that can be (and have been) empirically tested, and they’ve all be disconfirmed. Intelligent design doesn’t have any definite entailments at all.

    And what Sober does is call it intelligent design and then treat it as if it’s Creationism.

    But the point is that if you discard the theological claims then evolutionary arguments regarding perfection (or lack thereof) become utterly vacuous and the alleged evidence for evolution disappears.

    *poof*

  29. phoodoo: The best combination, huh?

    He’s still looking for the best genetic code. And he’ll continue to be an atheist until he finds it. Reminds me of the guy who claimed he’d become a believer when he could breathe vacuum.

  30. Joe Felsenstein: Just to attempt an answer to the question of where the quote comes from: Elliott Sober’s Evidence and Evolution, page 109.

    Wouldn’t be surprised at all to find it in more than one of his books. I’ll have to compare the two.

  32. Rumraket: I am saying that given some constraints, there is going to be some combination of alleles that give some organism from some species the highst attainable fitness, and any possible genetic deviation from this combination of alleles, is going to result in lower reproductive success.

    You mean the genetic code didn’t evolve in isolation? Or maybe the genetic code is more perfect in some species than others, eh?

  33. Mung: [responding to my guess as to where the quote in Mung’s post was]

    Wouldn’t be surprised at all to find it in more than one of his books. I’ll have to compare the two.

    I didn’t see a copy of either book — I based this on the guess that it was in Evidence and Evolution and an online Table of Contents. So I yield to Mung’s recollection that it came from Philosophy of Biology.

  34. Joe Felsenstein: When made by creationists and ID supporters, it is intended to persuade the audience that natural selection does not work to improve adaptation.

    See. They just can’t escape the teleological language.

  36. Mung: It’s from Sober’s Philosophy of Biology, Second Edition.

    iirc:Chapter 2 Creationism. Section 2.6. I’ll confirm this later today.

    Yup. Section 2.6 is titled “The Problem of Predictive Equivalence.”

    p. 42

  37. keiths:
    A comment of mine (directed toward phoodoo) was guanoed and can be found here.

    Probably would have been easier for you to just paste where you admitted your mistakes.

    Trump struggles with that too. And he’s President, so you should feel good. You could be the President!

  38. phoodoo:

    Probably would have been easier for you to just paste where you admitted your mistakes.

    Probably would have been easier to mail you hardcopies, since these computer thingies have you baffled.

    Note that newton had no difficulty. How do you suppose he did it? Was it magic?

    Hint: It may have something to do with the fact that newton is not burdened with the kind of mind that thinks that bad haircuts are the moral equivalent of being burned alive, and that to complain about either is petty.

  39. Alan:

    Now that is misrepresentation again. Variation is the source of new genetic material. It only becomes beneficial if positively selected.

    keiths:

    That’s completely backwards, as Glen pointed out.

    Alan:

    He did and he added

    It is positively selected only if it is beneficial, other things being equal.

    And I wonder what “all things being equal” means as the same genes can be either beneficial or deleterious depending on the niche.

    This isn’t difficult, Alan. “Other things being equal” includes the niche.

    A population occupies a niche. A variation arises in the population. The variation is either beneficial, neutral, or deleterious. If the variation is beneficial, then it can be positively selected for.

    So Glen was absolutely right to challenge this statement of yours:

    Variation is the source of new genetic material. It only becomes beneficial if positively selected.

    You got it exactly backwards. The causality does not run in that direction.

    Have you considered taking an introductory course on evolution?

  40. phoodoo: Probably would have been easier for you to just paste where you admitted made your mistakes.

    No Way! That would have taken forever.

  41. Joe Felsenstein: I based this on the guess that it was in Evidence and Evolution and an online Table of Contents.

    Not a bad guess actually. The book drops the chapter on Creationism and replaces it with a chapter on Intelligent Design. The chapter on Intelligent Design is Chapter 2. And there’s a section in that chapter on “The No-Designer-Worth-His-Salt Objection.”

    phoodoo will no doubt love this:

    “…natural selection does not necessarily lead to perfect adaptation, whatever that might mean.”

    – Evidence and Evolution p. 127

    If “perfect adaptation” is meaningless, can’t we somehow by some means accessible only to science make “imperfect adaptation” meaningful?

  42. Here’s an awesome quote-mine!

    I think creationists are right …

    – Elliott Sober (EaE p. 128)

  43. Another awesome quote:

    It is important to recognize that the phrase “evolutionary theory” is too vague when the subject of testing is broached.

    – Elliott Sober (EaE p. 364)

    ETA: Not that anyone here ever claimed that evolutionary theory is testable.

  44. Kantian Naturalist: Creationism is a scientific theory — but a bad one, and it would be unreasonable to maintain it in light of evolution (just as it is unreasonable to maintain geocentrism). Intelligent design isn’t even a theory.

    And the reason Creationism cannot be taught in public schools is … ?

    I’ve been posting here for quite some time now, and I can’t recall you ever responding to someone who claims that Creationism is not a scientific theory by informing them that they are wrong and that Creationism is in fact a scientific theory.

    Can’t say you’re alone though. Who doesn’t like to have their cake and eat it too?

  45. Surely, if we can learn anything at all from Dawkins’ WEASEL program, it is that evolution is an optimization algorithm that can in fact find the perfect solution.

    Except when it can’t. LoL!

    Evolutionists simply have too much evidence for their theory. They can’t keep it all straight. A string in a software program can have the highest fitness possible, but that’s not evidence for intelligent design.

  46. Joe Felsenstein: When made by creationists and ID supporters, it is intended to persuade the audience that natural selection does not work to improve adaptation.

    Don’t blame Creationists and ID supporters Joe.

    Is there a single evolutionist here who can distinguish natural selection as cause from natural selection as effect?

    For example, when a claim is made that natural selection is simply differential reproduction, is natural selection the cause or the effect? Both cause and effect?

  47. Rumraket: Your retreat from this position here is so obviously ad-hoc. You would be positively hysterical had it been found to be the best version.

    All you’ve done is take a premise that was an assumption and add to it yet further assumptions. Congratulations!

    Your evidence that I retreated is nil. Your evidence that I would have been hysterical is nil. You’re a fine example of a TSZ atheist skeptic. Keep up the good work.

  48. phoodoo: Probably would have been easier for you to just paste where you admitted your mistakes.

    Trump struggles with that too.And he’s President, so you should feel good. You could be the President!

    He couldn’t do worse.

  49. keiths:
    Note that newton had no difficulty. How do you suppose he did it? Was it magic?

    It was a miracle

  50. Mung: phoodoo will no doubt love this:

    “…natural selection does not necessarily lead to perfect adaptation, whatever that might mean.”

    – Evidence and Evolution p. 127

    You know it was phoodoo’s point that perfect adaption was an assumption of evolutionary theory, so I doubt he will love it.

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