Is biology reducible to physics?

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We have folks on both sides of this question, so it should make for an interesting discussion.

(I’m a ‘yes’, by the way.)

257 thoughts on “Is biology reducible to physics?”

  1. walto,

    ETA: One other point is that the claim that what we do when we mean something is “syntax-based” is either irrelevant (if it means it entirely complies with physical laws) or it’s question-begging. Are we talking about comportment with physics or with Searle’s closed dictionary loop?

    Here’s how I put it to Bruce in the other thread:

    In these discussions, it’s best to think of “syntactic” as meaning “operating without regard to meaning at the current level or above.” Don’t think of it as strictly involving the manipulation of symbols according to formal rules — that’s true in other contexts, but not here.

    Physics is syntactic because (contra Neil) it operates without regard to any assigned meanings (at any level).

    The human in the Chinese Room operates syntactically with respect to higher levels, because the meanings of the Chinese symbols don’t factor into his manipulations of them. He’s just following the rules.

    Looking downward, however, we can of course see that the human is operating semantically in interpreting the rules as they are expressed in English.

  2. keiths: No, dependence is the issue, not reducibility.

    Of course reducibility is the issue.

    If you can name a property that genuine intentionality depends on, that is present in humans but not in two-bitsers, then you can justify your claim.

    I have no idea what you mean by “depends on.”

  3. keiths:
    walto,

    Appeals to intuition make poor philosophical arguments, unless you can provide good reasons for trusting your intuition with respect to the question at hand.

    Thanks for the tip!

  4. Bruce, to walto:

    If misrepresentation relates to “normal function” in the evolutionary and learning history, then since the swampman did not have that history, his representations are not subject to those norms, hence they are not the same as yours (even assuming he is a physical duplicate of you).

    Which I think is a good reason for abandoning Millikan’s idea that the true meaning of a representation relates to its “proper function” as defined by its evolutionary history.

    But I’m still struggling with why the assumption of physical duplicate would not imply that the right history was built into the duplication process. Sort of like a Star Trek transporter.

    Swampman is a duplicate of Davidson purely by coincidence. The lightning bolt rearranges the atoms randomly, so a physical duplicate of Davidson isn’t inevitable or even likely. It’s vanishingly unlikely, and it’s pure luck when it actually materializes.

    Since it’s pure luck, there is no causal connection with the old Davidson, and thus no shared history from which to define “proper function”.

  6. keiths:

    No, dependence is the issue, not reducibility.

    walto:

    Of course reducibility is the issue.

    No, reducibility is not required. Dependence is enough.

    I have no idea what you mean by “depends on.”

    Genuine intentionality depends on X if X is a prerequisite for genuine intentionality. No X, no genuine intentionality.

    Here’s how I put the question yesterday:

    This is what Dennett and I believe.The two-bitser’s intentionality is the same kind of intentionality that humans have, though vastly less complicated.

    On the other hand, you say that those are definitely not instances of the same kind of intentionality. One is merely metaphorical and the other is genuine.

    If so, then the following must be true of at least one property X:

    1. X is a property possessed by humans.
    2. X is a property not possessed by two-bitsers.
    3. X is a prerequisite for genuine intentionality.Entities lacking X cannot exhibit genuine intentionality.

    “X is a prerequisite for Y” does not mean that Y is reducible. You’ve heard of nonreductive physicalism, right?

  7. For all any of us knows, breathing is a “prerequisite” for intentionality. That’s an example of why “depends on” is of no interest.

  8. BTW, do you have some intuitions regarding what is and isn’t a prerequisite for intentionality?? If so, please share them!

  9. Bruce,

    I like KN’s ideas because they seem to sidestep the whole derived versus original intentionality issue and concentrate and what the organism is rather than how it came about.

    KN doesn’t really sidestep the original-vs-derived question; he just shifts the dividing line. For him, organisms ranging from humans all the way down to bacteria lie on the “original” side of the intentionality line, but two-bitsers presumably lie on the “derived” side.

  10. walto,

    For all any of us knows, breathing is a “prerequisite” for [genuine] intentionality. That’s an example of why “depends on” is of no interest.

    That’s bad logic.

    1. Suppose that J is a property that depends on X, and that for all we know, it might also depend on Y.

    2. Now suppose that entity A exhibits properties X and Y, and that entity B definitely does not exhibit property X.

    3. We can conclude that B does not exhibit property J, precisely because J depends on X, which B does not possess.

    4. Therefore, it’s incorrect to claim that “depends on” is of no interest.

  11. Gregory,

    What’s the difference between biology being reducible to physics or law (jurisprudence) or ethics being reducible to physics?

    There’s no fundamental difference. It’s all physical.

  12. walto,

    BTW, do you have some intuitions regarding what is and isn’t a prerequisite for intentionality?? If so, please share them!

    I have! To repeat, I think that original intentionality — the kind of intentionality that would be exhibited by a true semantic engine, if such things existed — is impossible, because real engines respond only to syntax, not semantics. This, in turn, is because meaning does not enter into the laws of physics. The flip-flop that Neil and I discussed operates strictly according to the laws of physics. Change the meaning assigned to its inputs and outputs all you want; it will continue to operate in the same way, because the laws governing its operation do not take meanings into account. The same is true of neurons.

    Original intentionality is impossible, and actual intentionality is of the “sorta” kind — syntax masquerading as true semantics, to a greater (e.g. human) or lesser (e.g. two-bitser) extent.

  13. keiths:
    walto,

    That’s bad logic.

    Really? Let’s see, shall we?

    1. Suppose that J is a property that depends on X, and that for all we know, it might also depend on Y.

    2. Now suppose that entity A exhibits properties X and Y, and that entity B definitely does not exhibit property X.

    3. We can conclude that B does not exhibit property J, precisely because J depends on X, which B does not possess.

    4. Therefore, it’s incorrect to claim that “depends on” is of no interest.

    Classic. Thinking about football (J) depends on breathing (X) and for all we know digestion (Y) too (premise). A pantry moth (A) in my house exhibits respiration and digestion (premise). My can opener (B) definitely does not breathe (premise) Now I conclude that my can opener cannot think because you told me (right up front!) that thinking about football depends on breathing.

    That’s just really great stuff and I’m glad somebody has written it down.

    What I really love is that neither entity A (the pantry moth) nor Y (digestion) shows up in your “conclusion”: they’re only introduced in premise (2) for the pointless complication of another fabola keithsian “argument.” They’re like cameos! [FWIW, I was thinking Jennifer Garner might be cool as the pantry moth.]

    In spite of the obvious brilliance at work here, my own advice, based on what I know about “depending” and digestion is: Don’t quit your day job.

  14. walto,

    What I really love is that neither entity A (the pantry moth) nor Y (digestion) shows up in your “conclusion”: they’re only introduced premise (2) for the pointless complication of another fabola keithsian “argument.” They’re like cameos! [FWIW, I was thinking Jennifer Garner might be cool as the pantry moth.]

    Okay, let me spell it out for you. Let A be a human, and B a two-bitser. Let J be genuine intentionality. You’ve already defined “genuine intentionality” as whatever kind of intentionality a human has, so we already know by your definition that A exhibits genuine intentionality. That’s why it doesn’t appear in the conclusion.

    As for why Y doesn’t appear in the conclusion, I hope that’s obvious. B does not possess property X, so it cannot possess property J. Whether it possesses property Y is irrelevant to that conclusion.

    Classic. Thinking about football (J) depends on breathing (X) and for all we know digestion (Y) too (premise). A pantry moth (A) in my house exhibits respiration and digestion (premise). My can opener (B) definitely does not breathe (premise) Now I conclude that my can opener cannot think because you told me that thinking about football depends on breathing.

    I’m not sure what you’re complaining about. That is a valid argument (though not a very interesting one, due to your choice of variable assignments). If the premises are true, the conclusion is true. Don’t you agree?

    My conclusion holds:

    4. Therefore, it’s incorrect to claim that “depends on” is of no interest.

  18. keiths:
    walto,

    Can you identify a flaw in my argument?

    Ha ha.

    ETA: (I love when you say “argument” to describe something you’ve written.)

  19. Seriously, though. 3 follows from 1, basically. So it’s valid (not including 4, which is out of nowhere). It’s very inelegant and also completely pointless, though.

    But as I’ve said, it’s funny, so it does have that going for it.

  20. Getting back to Garner. I think using her for a pantry moth has a nice irony to it, but I don’t know–maybe it’s too subtle?

  21. keiths:

    Can you identify a flaw in my argument?

    walto:

    Ha ha.

    ETA: (I love when you say “argument” to describe something you’ve written.)

    Okay. Well, if you come up with a counterargument, let me know.

    ETA: Quoted the comment I was responding to.

  24. keiths:
    walto,

    I have!To repeat, I think that original intentionality — the kind of intentionality that would be exhibited by a true semantic engine, if such things existed — is impossible, because real engines respond only to syntax, not semantics.This, in turn, is because meaning does not enter into the laws of physics.The flip-flop that Neil and I discussed operates strictly according to the laws of physics.Change the meaning assigned to its inputs and outputs all you want; it will continue to operate in the same way, because the laws governing its operation do not take meanings into account.The same is true of neurons.

    Original intentionality is impossible, and actual intentionality is of the “sorta” kind — syntax masquerading as true semantics, to a greater (e.g. human) or lesser (e.g. two-bitser) extent.

    I didn’t see this post before. If this does, as you claim, represent your intuitions regarding intentionality (and is not, as it appears to be, simply a restatement of Dennett), I’d like to remind you that you recently opined that use of one’s intuitions was a bad method in philosophy.

    Methodology aside, as I don’t know what a “true semantic engine” is, I can’t assess it. I have some sense what people do, but, as you say that’s not true or “original” semantics, I don’t really know what you’re talking about. I take it you’re saying something like that God would be a true semantic engine. You could discuss that with some of the zanies here: I think that might be funny too.

    ETA: Maybe it’s ok to use Dennett’s intuitions but not one’s own? I don’t know, this stuff is SOOOO CONFUSING!!

  25. walto,

    If this does, as you claim, represent your intuitions regarding intentionality…

    They aren’t intuitions. That comment expresses an argument. “Intuitions” was your word, not mine.

  26. keiths:
    “We have folks on both sides of this question, so it should make for an interesting discussion. (I’m a ‘yes’, by the way.)”

    Why are you a yes?

  27. Can someone please explain how “natural selection” is derived from the laws of physics?

  28. Methodology aside, as I don’t know what a “true semantic engine” is, I can’t assess it.

    We’ve been through this before, but I’ll reiterate: a true semantic engine would be one that responded to actual meanings (as opposed to their syntactic approximations). As I said:

    …real engines respond only to syntax, not semantics.This, in turn, is because meaning does not enter into the laws of physics.

  29. Here’s the argument again, for convenience:

    walto:

    For all any of us knows, breathing is a “prerequisite” for [genuine] intentionality. That’s an example of why “depends on” is of no interest.

    keiths:

    That’s bad logic.

    1. Suppose that J is a property that depends on X, and that for all we know, it might also depend on Y.

    2. Now suppose that entity A exhibits properties X and Y, and that entity B definitely does not exhibit property X.

    3. We can conclude that B does not exhibit property J, precisely because J depends on X, which B does not possess.

    4. Therefore, it’s incorrect to claim that “depends on” is of no interest.

    walto:

    Seriously, though. 3 follows from 1, basically.

    No, #3 doesn’t follow from #1 alone. It requires #2 as well.

    Since #1 is a “depends on” premise, the conclusion is correct:

    4. Therefore, it’s incorrect to claim that “depends on” is of no interest.

  30. Mung:

    Can someone please explain how “natural selection” is derived from the laws of physics?

    It isn’t. Here’s how I put it to Glen:

    If you mean that the laws of physics by themselves don’t inevitably lead to peacock feathers, then I would agree. The initial conditions of the universe also matter, as do the outcomes of nondeterministic quantum events. But all three of those factors — the laws, the initial conditions, and the nondeterministic outcomes — are physical, so I would argue that the whole shebang is physical.

  31. Hmmmm. I asked:

    BTW, do you have some intuitions regarding what is and isn’t a prerequisite for intentionality??

    to which you responded

    I have!

    And then you rehashed your Dennett spiel.

    But now, you say:

    They aren’t intuitions.

    I tell you, I don’t know which keiths to believe!

    Oh, ETA: I removed a “/” at the end of this post
    And ETA 2: I added an “Oh” before the above “ETA”
    ETA 3: I added an “And” before ETA 2. (I know this kind of thing is important to you, keiths, and I just give, give, give.)

  32. keiths:
    Here’s the argument again, for convenience:

    walto:

    keiths:

    walto:

    No, #3 doesn’t follow from #1 alone.It requires #2 as well.

    Since #1 is a “depends on” premise, the conclusion is correct:

    4. Doesn’t follow from anything: it’s a complete non-sequitor and (2) is a mess. A smidge of it it is required to get (3) because it’s also screwed up and, as I said “basically” follows from (1) alone. The whole thing is a mess. As I said, valid (if you stop at (3)), but both inelegant and pointless. I think you should post it again for laughs though.

    Because it certainly IS funny.

    However. While you seem to have time to repeat yourself over and over again, (indeed it’s obviously one of your most favoritist things to do–when somebody tells you one of your posts is crap, you generally repeat it four or five times as if that could make it better), you simply WILL NOT answer my Jennifer Garner questions. I hate when you do that. Your posts are much worse than Jennifer Garner–in every way.

    ETA: I made the sentence “However.” begin a new paragraph. I might put it back where it was without telling anybody, though. I feel rebellious.

    Nah

  33. keiths:
    Mung:

    It isn’t.Here’s how I put it to Glen:

    I like it when you quote yourself. It shows a certain je ne sais quois. I mean, there’s only so much tread on the tire, right?

    ETA: I added italics to the French expression. Seemed classier. If someone thinks I should remove the italics and leave the post the way it was as a matter of internet courtesy, well, tough toenails, monsieur.

    ETA 2: I added a comma after “well” in the above ETA. (Actually, I don’t know if it’s ok to use “ETA” as a singular term the way I am here. If not, well, DOUBLE tough toenails!)
    ETA 3: I left out an “if” (after “know”) in ETA 2, which I’ve just inserted (unless I forgot).

    OK fuck it. I’m not doing this ETA stuff anymore. I’m going to go back to fixing typos without telling anybody. HAH!

  34. walto,

    You asked an irrelevant question:

    BTW, do you have some intuitions regarding what is and isn’t a prerequisite for intentionality?? If so, please share them!

    I gave you the benefit of the doubt and assumed that you were really asking for my thoughts on intentionality, which are relevant. But if you insist that you meant to ask the irrelevant question, my answer is:

    It’s irrelevant.

    🙂

  37. Natural selection is not derivable from the laws of physics, yet biology is reducible to the laws of physics.

  38. keiths:
    walto,

    You asked an irrelevant question:

    I gave you the benefit of the doubt and assumed that you were really asking for my thoughts on intentionality, which are relevant.But if you insist that you meant to ask the irrelevant question, my answer is:

    :)

    Oh, I get it. You weren’t lying before when you first said intuitions were bad and then said you HAD intuitions and then said you didn’t have intuitions. The idea is that, while it seemed like you first contradicted yourself and are now lying about it, what actually happened is that sometime in that sequence of bullshit, you were giving me the benefit of the doubt! You’re always so nice to me. I don’t deserve it.

    Not only should you not quit your day job, you should not take oaths.

  39. keiths:
    Richard T. Hugs,

    I think walto needs another hug.

    I think what I really need is for you to repeat one of your “arguments”: that always cheers me up! 🙂

  40. keiths:
    walto,

    I have no problem with either of those two ETAs.

    Which two? I hope you’re not saying you have a problem with some other one. That would really be a downer for me.

    ETA: 🙁

  41. keiths:
    Richard T. Hugs,

    I think walto needs another hug.

    While you’re at it Richard, if you’ve got a country house or something you’re not using, my fam could use a vacay. I mean, hugs are nice and all, but…..

    Wait a minute. I think this plea might be better if I stick a few numbers and a “therefore” in it and say it has steps. That’ll really impress, I bet!! I mean, it doesn’t have to actually make any sense, right?

  42. Mung,

    Natural selection is not derivable from the laws of physics, yet biology is reducible to the laws of physics.

    Read the thread title again:

    Is biology reducible to physics?

    “Reducible to physics” does not equal “reducible to the laws of physics”.

    …and then reread this:

    If you mean that the laws of physics by themselves don’t inevitably lead to peacock feathers, then I would agree. The initial conditions of the universe also matter, as do the outcomes of nondeterministic quantum events. But all three of those factors — the laws, the initial conditions, and the nondeterministic outcomes — are physical, so I would argue that the whole shebang is physical.

  43. walto,

    Regarding this comment: Like I said, if you come up with a counterargument, let me know.

    Likewise, let me know if you come up with a better reason than “because my intuition tells me so” for your claim that human intentionality is genuine while a two-bitser’s intentionality is merely metaphorical.

  44. Hahahaha.. “Counterargument” again!! You rock! 🙂 🙂

    That’s my keiths!

    But c’mon. Give the whole argument again. I love that thing.

  48. walto: While you’re at it Richard, if you’ve got a country house or something you’re not using, my fam could use a vacay.I mean, hugs are nice and all, but…..

    Wait a minute.I think this plea might be better if I stick a few numbers and a “therefore” in it and say it has steps.That’ll really impress, I bet!! I mean, it doesn’t have to actually make any sense, right?

    I’ve got a villa in Mallorca, but my aunt Sue is there right now.

  50. RTH,

    You can both have one. You are a weasel with a rag soaked in rabbit juice, Keiths.

    I’ll take a handshake and ten bucks instead. And who doesn’t drink a little rabbit juice on Saturday night?

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