Alvin Plantinga is widely regarded as one of the world’s leading Christian philosophers. Watch the video below and ask yourself, WTF?
So as not to spoil your fun, I’ll refrain from offering my take on the argument until readers have had a chance to comment.
Fair point. I did mention in the first post to Robin that we needed to assume a finite number of possibilities (which you also note later in your post) Finiteness falls out of quantum mechanics (something about only a finite number being distinguishable due to Uncertainty, I think, but I may be misremembering that).
So I should have said if there are only a finite number of outcomes and they all have probability greater than zero, then they will all recur an unlimited number of times as the number of trials grows without bound.
(So just to be clear, the number of universes is infinite but the number of configurations under a given set of constants and our physics is finite).
Just to try to be a little more clear, I’m not asking whether it’s possible for an identical person arising somewhere in the multiverse. (god no! Given my health issues, I really hope I’m not doomed to repeat this kind of life over and over and over!!) What I’m wondering is whether my particular locus of perspective will come around again. In other words, it is clear to me that each living animal on this planet has it’s own particular locus of perspective; there’s no personality out there (of which I’m aware) that can look out on the world from multiple bodies for instance. Assuming there is no soul (and I don’t believe there is), then a given locus of perspective is the product of a material system. Is it possible for that system to arise again in another body? Or is any given system completely unique to the entirety of the body and thus will never come around again, not even across multiple verses.
That’s not really my question, though it is a subset of my question. See above
Booooo…
😀
Hi BruceS. What I have to say is that everybody argument as if Plantinga said this:
or this
To me seems very different to what I understand Plantinga said. How can we discuss Plantinga arguments if we think that Plantinga said different things?
If there are only a finite number of configurations for the whole universe, including you then what could be different if that very same configuration arises again?
It seems to me that the only way one could say there is something different about first person perspective is if you believe there is something in first person perspective which is not physical. Or at least not part of the properties of the world covered by science to date.
If you are are dualist of some sort, then you are entitled to say that first person perspective might change. Even some sort of property dualism would do, eg if there are mental properties that current science does not address (and which are needed to explain first person experiences of things like smell or taste).
But if you do not accept any form of dualism, I think you must believe that first person perspective would also recur.
Can you explain to me how they are different.? It really seems to me they are saying the same thing.
For example, you did not mention modal properties, but P does in the video. That seems to be an important point that the KN and walto have discussed.
I should also say, as I noted in another post, that I think P’s conclusion in the video is true, regardless of the merits of his particular arguments. That as, I would agree that we are not the same as the particular atoms which happen to make up our current body.
But I think we do need some atoms in an equivalent configuration. I would guess that you think we don’t. So any argument that relies on what we can conceive about existing without bodies cannot take us any further than our starting assumptions about physicalism.
Nor can it defeat those assumptions.
In particular, because I am a physicalist, I cannot conceive of me existing without any physical body. I would guess that your worldview is such that you can conceive of existing without a body. And I think we would be stuck there.
But we weren’t discussing being born with an adult neuron configuration. We were discussing a duplicate existing somewhen in an alternate universe.
I do not think there is any such thing as memory, consciousness or personhood apart from the specific configuration of neurons, supporting cells, blood chemistry and connections. No way to download memory. No way to Star Trek transport. No way to copy or clone a person.
If a person is said to be more than a body, it is because the speaker does not understand the implications of configuration when using the word body.
No, if nobody understand the difference it doesn´t matter.
To me Plantinga is saying that only the atoms in the right configurations is not enouhg to explain me. You can change “body” for “the group of atoms in the right comfigurations” and his argument is the same. No matter the argument is wright or not. I do not agree with the argument as far as I understood it. Probably a five minutes answer is not enoguh to explain correctly thah kind of arguments.
I could agree that humans without bodies do not exists. Do you think that there are not physical (made of matter an energy)entities?
I have to butt in and say that all this sounds like a discussion of magic.
Someone please explain the difference.
BruceS,
Bruce, you write:
“I should also say, as I noted in another post, that I think P’s conclusion in the video is true, regardless of the merits of his particular arguments. That as, I would agree that we are not the same as the particular atoms which happen to make up our current body. But I think we do need some atoms in an equivalent configuration.”
I’d think a physicalist would respond that, just as there’s a sense in which my “mind” is not identical to that particular array of atoms that one finds at place p, time t, neither is my body. To the same extent that it’s still my body in spite of the changes in constitutents, it’s still what you call my “mind” in spite of those changes.
This is some combination of sophistry or equivocation.
A flame, a river, a brain, are all things that change constantly. We even have an aphorism to the effect that you can’t step into the same river twice.
When you say person or mind, you are referring to the river or the flame. Get that sorted out, and then continue the discussion.
“A flame, a river, a brain, are all things that change constantly. We even have an aphorism to the effect that you can’t step into the same river twice.”
That’s actually the point of the response, I think. Somebody says, “Hey, my mind can’t be identical to my body (or any part of it) because my body is always changing, and it’s still my mind we’re talking about.”
And the physicalist responds, “Yeah, so what–it’s still my body too. My body and my mind are alike in that they can survive these kinds of changes, just like a river can.”
It’s not so much that the river survives as it is how we use words for flame-like objects. That’s why I say the OP argument is a kind of equivocation.
It’s the same kind of equivocation that IDists engage in when discussing information or probability. It’s not a pretty thing coming from a professional philosopher.
Blas,
If the equals sign is understood to mean “is identical to”, then yes.
It’s the other way around. Plantinga uses ‘B’ to designate his body, and ‘A’ to designate himself, so he is saying that A can conceive of A existing without B.
Where did you get this? Plantinga doesn’t say anything like it, even if you swap A and B.
Yes, that’s Leibniz’s principle.
Yes, that’s Plantinga’s premise.
No. Again, Plantinga says nothing like this.
Petrushka, I’m not familiar with the stuff you’re complaining about with respect to ID (which I’m not surprised to hear is crap), but at least some philosophers are very careful when discussing these matters. As I’ve mentioned before, I’m particularly fond of Amie Thomasson’s book _Ordinary Objects_ and her paper “A Non-Reductivist Solution to Mental Causation” (which I’ve reprinted in an anthology).
The issue in your post is whether “X is F at t and X is not F at t+1” (or, better, “X is composed of A-Y at t and X is composed of B-Z at t+1”) are self-contradictory. I think it’s pretty clear that they’re not.
How Plantinga then applyes Leibniz`s principle? Which is the same statement applied to me, not able to be applied to my body?
petrushka,
walto was responding to this statement from BruceS:
Effectively, Bruce is taking ‘B’ in Plantinga’s argument to mean ‘a particular arrangement of particular atoms’, and he’s saying that Plantinga’s conclusion is actually correct if we take that definition. In other words, you aren’t ‘a particular arrangement of particular atoms’, but your body is.
Walt is simply pointing out that most physicalists don’t accept that definition of the body. The particular atoms don’t matter. Take a calcium atom out of my bone and replace it with a different calcium atom. It’s still my body. Replace all of the calcium atoms in my body with different calcium atoms. It’s still my body. Replace every atom in my body with a different atom of the same element. It’s still my body.
I think Plantinga would agree. He’s not merely saying that you transcend the particular set of atoms making up your body; he’s saying that you transcend any such set of atoms.
Blas,
If ‘A’ is Alvin and ‘B’ is Alvin’s body, then “A could conceivably exist without B’ is true, but “B could conceivably exist without B” is not.
I think I get what you’re saying. My question stems more from the idea of where the locus is located in the body and how much “body” is required to form a given locus.
For example, I’ve had four kidney transplants. I really don’t see my locus of perspective – my first person “me” – as changing because a bunch of other people’s kidneys were dropped into me. As such, I don’t feel my locus is connected in any way to my kidneys. I’ve also lost a lot of hair and yet don’t seem to have lost any of my first person perspective. Thus, I don’t think my locus of perspective is contained in my hair. I therefore hypothesize that I could still have the exact same locus of perspective if I had completely different hair.
Do you see what I’m getting at? How much of the physical body I currently have is required for my particular first person perspective to exist? I tend to think that the only thing needed is part of my brain, but maybe not. Maybe my whole brain is needed, exactly as it is currently arranged, for this particular first-person perspective to exist. That’s the question I’m wondering.
Ahh…well I wasn’t, but ok. 😀
Yes…on this I completely agree.
Again, yes. With this I agree.
keiths,
Exactly. Thanks.
I think there’s plenty of evidence from how people’s personality can change somewhat or drastically following brain trauma from disease, injury or surgery that confirms the premise.
I still don’t get the “therefore God” step in all these dualist arguments. Where’s the logic?
Robin said:
Bruce said:
This is addressed through the Boltzmann Brain thought experiment. Robin objects that if the priors didn’t occur, the memories/person cannot be the same. Bruce says that if another universe matched our history quanta for quanta, the memories would necessarily be the same.
The point of the Boltzmann Brain scenario is that no such priors are necessary, and, in fact, the infinite number of priors necessary throughout the history of the universe to generate a specific state here and now make it much more likely that the necessary states for those memories simply manifested randomly somewhere in the infinite array of universes.
An analogy would be a photograph of you and your friends at some event. The Boltzmann Brain thought experiment (though it is about what appears to be a “universe” and not specific things in it) holds that if the multiverse theory is true, it is infinitely more likely that the photograph spontaeously assembles out of quantum fluctuations than it is that an entire universe and billions of years of quantum events all lead up to the specific elements necessary to produce that photograph through continuous, cause-and-effect materials and forces.
Extrapolating that, “you” – including your memories and all your conditions, are not dependent upon past events actually occurring; they’re only depending upon all current states of your current existence. X didn’t actually have to occur in the past to have what feels like a memory of it; it just depends on the states that produce the imagery and the sensation of it being a memory.
Let me give you an analogy from personal experience. I’ve had dreams where I’m in some entirely fictional city – like something out of a novel. I knew the people around me – names, whether they were friends or not, etc. I had memories in this dream – who I was, what I had done in the past, other adventures we had been on. I was aware of what I was trying to do in the dream.
When I awoke, I couldn’t place any of that information in context with my real life including anything I’d read or movies I’d watched. The interesting thing in the dream was that my mind apparently manufactured memory to go along with the fiction of the dream.
Under naturalism and the multi-world scenario, there’s nothing to prevent another “you” from simply “manifesting” somewhere, even somewhere else than your current world, completely intact with all memories.
Robin:
Alan:
I think you’re misunderstanding the question. Robin wants to know whether his entire brain, exactly as it is, is necessary for his “particular first-person perspective” to exist.
I think we can safely say the answer is no. Kill a single random neuron in Robin’s cerebellum, and Robin will still be Robin, even though his brain has changed.
Alan,
Dualism and theism are distinct. It’s possible to be an atheistic dualist.
Plantinga is a theist, of course, but his argument doesn’t depend on that, nor does it lead to that conclusion.
When you pursue these kinds of thought experiments (many-worlds, boltzmann brains, quantum immortality), the ability to die and re-manifest in a different kind of existence (universe) with your memories intact not only becomes possible, it becomes pretty much a necessity.
If that doesn’t meet the definition of an afterlife, I don’t know what does.
He would be wrong, or at least not justified by any evidence.
But I still say he is equivocating by implying that a body is an inert lump, when that is not what science would say.
Let’s say for the sake of argument, that there is a poison so potent that one molecule can kill a person. Let’s call it the Schroedinger poison. So one molecule would make the difference between a dead person and a live person.
When we speak of a person, we are usually speaking of a living, breathing, behaving system, not an inert lump of molecules.
But it’s still a configuration of moecules, even if highly sensitive to small differences.
Why do you think he implies or tries to imply that a body is an inert lump? I think what what he wants to show (but, IMO can’t) is that, even if his body is an animated energetic entity, it’s not identical to his mind.
petrushka,
Plantinga doesn’t say that, and his argument doesn’t depend on it.
Let ‘B’ denote a living, breathing, active body, constantly interacting with its environment. Then it is still true that A can conceive of existing without B.
That premise is fine. The problem with the argument lies elsewhere.
William:
That’s not true. Boltzmann brains are more likely in some multiverse scenarios, less likely in others. It depends on the physics.
Sean Carroll addressed this in his debate with William Lane Craig.
Now I am confused. What would a dualist atheist hold as premises and why?
Well, I’m not sure. If you insert “exactly” then the answer must be trivially “yes”. If you allow “almost identical” then sure, one can sustain severe injury and still be recognizably who you are, especially from your own perspective. Others may see changes that you yourself do not. But this seems a digression from what interests me. That is where does “God” fit into Plantinga’s argument.
ETA
I mean if it doesn’t involve some claim about “God” then what point is he driving at?
Alan Fox,
Such a one might give exactly the same, entirely non-theological (even though IMO bad) argument that Plantinga gives above. FWIW, there have been lots and lots of philosophers through the ages who have been both atheists and dualists. There’s even one, McTaggart, who was an atheist while believing in the immorality of the soul.
Alan,
Here is Robin’s question:
Alan:
It’s not a digression from what interests Robin!
walto,
Did you mean ‘immortality’?
keiths,
Hahha! I did!
Alan,
To be a dualist, you just have to believe there are two kinds of stuff, the physical and the mental. You can believe in an immaterial soul or mind without believing in God.
And which of that statements you thing it is not true?
Blas,
I think they’re all true, but those are just the premises. It’s the rest of the argument that’s bogus.
Bruce has a nice summary of the argument here, and I explain my objection to the argument here.
Bruce,
How did they resolve the problem? Something tells me they didn’t just kill one of the two Rikers.
But the argument of Plantinga, in the way you posed it, do not need that what he conceive is or is not true. What he conceives could be totally false, the point is that “I” can conceive that for me, but I can´t conceive it for my body.
1) If ‘A’ is Alvin and ‘B’ is Alvin’s body, then
2) “A could conceivably exist without in a coccrache body”
3) but “B could conceivably in a coccrache body” is not.
2) is true no matter it is impossible or not correspondant with reality.
In my opinion your statement of the argument do not comply Leibniz`s principle 2 and 3 are not equivalents.
Blas,
Plantinga’s argument is that A and B can’t be the same thing, because if they were the same, then we wouldn’t be able to imagine something about A that we couldn’t also imagine about B.
He’s wrong. Suppose C and D are different names for the same thing. It’s entirely possible for someone to imagine something about C that he couldn’t possibly conceive of with regard to D, but that doesn’t magically force C and D to become separate things.
There is no actual difference between C and D. The difference is entirely in the conceiver’s mind, and reality is not forced to conform to the conceiver’s error.
Again, I agree with that conclusion as I understand your wording, or at least I agree it is a possibility that is well within the bounds of scientific investigation.
I transcend any particular set of atoms
But I add the constraint that I don’t transcend the set of sets of atoms which can be arranged in to make a physically equivalent substrate to mine (equivalent in terms of causal powers). I agree P probably wants to conclude that, although I cannot remember him taking it that far in the video (but I have not the patience to watch it again…).
But as I said in other posts, I think the disagreement comes right at the first premise since I think the full argument would be (roughly to make my point)
a. I can conceive of a possible universe where physicalism is false.
b. I can conceive of my mind as something different from body.
c. I cannot conceive of my body as separate from my body.
d. Therefore I am something different from my body.
e. Further, from a, my mind can exist without any body.
I don’t think you can get e without a. I so it comes down to accepting a if you want e.
There are still other issues: multiple instances of me or the right causal connections to re-implementations of me to preserve identity. Those were the issues in one of my other posts.
Bruce,
I think (a) is a given. Dualism is perfectly conceivable, even if false. Humans have been dualists for most of our history.
ETA: Also, I don’t think (a) and (e) are essential to the argument.
Then you are against the Leibniz´s principle.
Or you are saying that when I say me, I always say my body. Are two words one reality. Like the same thing called C and D. I can say the name of the thing is a closed letter. I can apply to C not to D?
Mr Wikipedia knows all (or at least all nerd stuff):
Second Chances
The relevant gist: they both think they are Riker but one agrees to change his first name and move on with his life.
Another relevant point is that the woman who was Riker’s lover in the past tries to rekindle that relationship with the second Riker, so she seems to think it is him as well.
Of course, it is just a science fiction story.
Or should I say, it is just a philosophical thought experiment.
Bruce,
My point about the multiverse is that this statement isn’t necessarily true:
If the probability of “the state with you” is zero, then it might occur only a finite number of times, even across an infinitude of universes. If that finite number is one, then there are no duplicates of you.
Blas,
No, I accept Leibniz’s principle.
Think of it this way: Suppose C and D are just different names, or concepts, referring to some actual thing X. Plantinga’s argument shows that the concepts C and D are different, but it doesn’t show that C and D refer to two distinct things. They still both refer to X.
Mind is something a body does. Mind is a subordinate aspect of the body. Of course they are not the same. Mind is a subset.
ETA: All you have to do to to resolve the subset quandary is ask two questions: 1. Can you have a mind without a body (and if so, provide an instance), and 2. Can you have a body without a mind?
Examples of (2) abound. Examples of (1) are nonexistent.