19 November 2014

What would it take to change my mind?

This past weekend I had lunch with a buddy of mine who is a devout Christian. He had no idea that I'm an atheist (I don't make a big deal out of it in my day to day life) until he saw me 'like' this Facebook meme:

It was a telling moment in the 'debate', such as it was, when the two were asked what would change their minds. Nye was very specific about how the theory of evolution could be undermined and, though improbable, evidence could emerge that would force him to change his mind. That's the beauty of an evidence-based worldview: your beliefs are contingent on evidence. Ham, meanwhile, stated (in so many words) that he's a Christian and that nothing will change his mind about the truth of the Bible.

I'm reminded of one of William Lane Craig's debates (I can't find the vid, sorry) in which he derided atheists like Richard Dawkins as being "cocksure". This, despite the fact that Dawkins, much like Nye, has said that evidence could change his mind, while Craig said this:
... even in the face of evidence against God which we cannot refute, we ought to believe in God on the basis of His Spirit's witness.
What is more "cocksure" than a belief that, even in principle, cannot possibly be wrong?

Well, my friend asked me what it would take to change my mind. If indeed evidence would do the trick, what kind of evidence would be enough? This, roughly, was my answer:

1. A coherent concept of God

I think one of the most important arguments against the existence of God is theological noncognitivism: the idea that the concept of God is so ambiguously defined as to render it virtually meaningless.

Take for example Craig's claim that God is a timeless, changeless, disembodied mind. First, there is the problem of what a "disembodied mind" even is, which I talked about in detail in a post "What is God's mind like?", in which I said,
[...] we've never seen or studied a disembodied mind. All the minds we're aware of require this process of subconscious cognition arising from the brain to produce conscious awareness and linguistic meaning. But more to the point, if God is omniscient as he is generally conceived, then he must know his own mind. He must be consciously aware of what are, for us, subconscious processes that allow us to experience a coherent conscious experience. But how can this be? It's a paradox in terms.
I'm not saying a disembodied mind can't exist. I'm saying that whatever a disembodied mind is, it's absolutely nothing like any mind we have ever encountered — so much so that it's not really clear in what sense it's a "mind" at all.

The problem gets compounded when you add "timeless" and "changeless". First, what does it mean for something to "exist timelessly"? We've never encountered such existence. It would, by definition, exist in relation to nothing. What does that even mean? And if God has a thought, it logically entails time — a moment before, during, and after having the thought. Maybe God doesn't "have thoughts" as we'd generally conceive it, but that would just reinforce how ambiguous a "disembodied mind" really is. And what is a mind that does not change? Any thought or action constitutes a change. A changeless mind is hardly a mind at all, as it is by definition a mind that cannot think.

Then we have the myriad of omni-paradoxes, which theologians purport to 'solve' by making omni-qualities highly conditional, in which case one wonders what the point is in using the terms at all.

Lastly we have the even more obscure "pure being" claim of Scholasticism, in which any of God's distinct properties (disembodiment, maximal power/love/knowledge, timelessness, transcendence, etc.) are somehow identical to God's mere existence. Again: what does that even mean? Thomists like Ed Feser try to sweep the problem under the rug by saying that our descriptive language is only analogical, not univocal:
Thomists, when attributing intellect, knowledge, etc. both to God and to us, we have to understand the relevant terms analogously rather than univocally. It’s not that God has knowledge in just the sense we do, only more of it. It’s rather that there is in God something analogous to what we call knowledge in us, even if (since He is absolutely simple, eternal, etc.) it cannot be the same thing we have.
But this doesn't resolve the ambiguity at all — on the contrary it fully admits the ambiguity! Is is literally the admission that whatever God is, it cannot be described with any sort of semantic precision. This retreat to proclaiming God to be ineffable may wash with theists looking to justify an assumption which they have already declared to themselves immutable, but it cannot get a rational skeptic from here to there. One cannot claim that God's existence or nature can be inferred using the semantics and metaphors of human logic, and then when challenged to define what God exactly is claim that those same semantics fall short. It's a classic pedantic sophistry, an unabashed bait-and-switch.

So, that's the first thing: before I can take claims about God seriously, theists have to be able to coherently define it. Then what?

2. Evidence that follows from God's existence and nature

Aside from the whole steaming pile of "necessary being" bullshit, there's one more area in which God's existence ought to be more relevant: explaining the world around us.

In my conversation with my friend, I used the example of prayer. Let's say that a child has terminal cancer. The church gets together and everyone prays diligently. Miraculously, the child recovers. Naturally, the believers will attribute this to an answered prayer. Praise God! But what happens if the child dies? The believer will still claim that God answered the prayer — but they will claim that God has a Divine Plan, and that ultimately God will do His will.

There are two problems here. The first was beautifully articulated by the late comedian George Carlin:
Remember that? The Divine Plan. Long time ago, God made a Divine Plan. Gave it a lot of thought, decided it was a good plan, put it into practice. And for billions and billions of years, the Divine Plan has been doing just fine. Now, you come along, and pray for something. Well suppose the thing you want isn't in God's Divine Plan? What do you want Him to do? Change His plan? Just for you? Doesn't it seem a little arrogant? It's a Divine Plan. What's the use of being God if every run-down schmuck with a two-dollar prayerbook can come along and fuck up Your Plan?
The second is that if God is always answering prayers as either "yes", "no", or possibly "wait", then how does one discern the difference between an answered prayer and something that would have happened anyway?

Take the child's 'miraculous' recovery. Even in rare and deadly types of disease, there is a small probability of survival. Stage 4 pancreatic cancer has something like a 5% survival rate. So 95% of the people who get it will die, but 5% will experience a seemingly miraculous, against-all-odds recovery. If it's an atheist like Lance Armstrong, who recovered from Stage 4 testicular cancer, it's just a lucky break. But to a believer, it was the Hand of God answering a prayer. What evidence could a believer point to that could demonstrate the difference to a rational skeptic?

Many believers who fancy themselves more 'sophisticated' have gotten away from making claims about what, exactly, God does in the world, because it turns out that the Divine Hand of God is a pretty lousy explanation for... well, anything. Still, some will try to shoehorn God into the gaps — perhaps, like Francis Collins claimed in his book The Language of God, God miraculously intervened to create life before letting the cruel indifference of evolution run its course. Most believers, though, are not academic theologians. They perceive miracles in their day to day lives, small and grand events alike that seem to be evidence for God — a near-death experience, a lucky escape from a potentially fatal accident, the generosity of a stranger, etc.

I am certainly in no position to declare that God is not at work in those ways. But what I do know is that, like the semantic ambiguity essential to the various 'necessary being' arguments, it may be sufficient to appease someone who is already a believer, but it won't get a rational skeptic from here to there. My view that the mis/fortunes we all experience are often random ("often" because technically acts of others are not necessarily random) comports perfectly well with the reality that surrounds me. The reason it looks like human suffering is indiscriminate is because it is, not because there is some ineffable Divine Plan underneath it all. My skepticism grants me parsimony that theists will never grasp. 


Whether one believes that God actively orchestrates the world around us or just somehow sustains all of existence, the evidence is simply unconvincing to any rational skeptic. Until the believer can meet this reasonable burden of evidence, there is simply no reason to think that God exists.

By the by, my friend shared what would change his mind as well. He is a Christian, and claims he has had a transformative experience through his salvation. What could change his mind? In his own words: "Nothing".

14 November 2014

Closing thoughts on model-dependent realism

Whenever I engage in debates with theists, I'm reminded of Tim Minchin's analogy of such discussions — that two people trying to win a debate while operating from completely different sets of assumptions are like two tennis players trying to score perfectly executed shots from the opposite ends of separate tennis courts. After pouring several hours of writing and research into my previous post, offered as a counter to Steven Jake's dismissal of Model-Dependent Realism (MDR), reading his response this week left me with a feeling like we were two ship captains in battle, and I'd just punched a massive hole in his ship's hull with a blast of broadside cannons — and yet, as his vessel sank and his crew abandoned ship, he stood on the deck shouting, "Haha, you missed!"

It's not that I feel Steven's response fails to adequately rebut my case so much as I feel that it doesn't address my case at all. I wrote my critique with the intention of clarifying what I felt were sorely misguided assumptions on his part about what model-dependent realism is; in his response, Steven has shown a frustrating unwillingness to critically examine those assumptions, repeated arguments I'd already addressed, and ultimately attacked a caricature of my actual position. He's said enough that I think it's worth replying to a few key points, but I'll let him have the last word should he choose — this post will be my closing thoughts on the matter.

With that, let's dive into his post, the entirety of which can be read on Steven's blog here. He begins:
I never claimed that MDR stated that models conform to reality—in fact this is my point of contention with MDR! I agree that MDR states that our models are only interpretive structures, so to speak.
Let me first clarify my point of contention here.This is what Steven wrote in his first post:
First, let it be understood that MDR does not claim that if two theories can both accurately describe or predict the same observations, then we cannot, at the moment, determine which theory actually conforms to objective reality. No, MDR is claiming that neither theory conforms to reality more than the other—that is, neither theory is more real than the other.
My issue here is that Steven is already off the mark with the whole concept of "conforming to reality". How do we know that reality exists? Presumably, through our sensory data. But it is not that simple, because our brains don't read sensory data as though we're watching a film or looking at a photograph — rather, our brains construct a model of reality based upon that data, and we navigate that phenomenological model with a process of reasoning heavily informed by subconscious metaphor. Unless one subscribes to naive realism, it's untenable to claim that we have direct, unfettered access to some singular, absolute reality — few would disagree that our conscious models of the world are often wrong, as illustrated by the rather striking number of cognitive biases to which we are susceptible.

Of course, as Steven points outs, we agree that objective reality exists. This is trivially true. But the important distinction that MDR makes is that our very conceptualization of reality is a conglomerate of distinct and overlapping models that work at different frames of reference. MDR is not comparing models against some singular "objective reality" — rather, it states that our very concept of what objective reality is is derived from our ability to construct models and test them against observation. 

Steven continues,
But for MDR to state that nothing at all can conform to reality, or that talk of models conforming to reality is meaningless, is to refute oneself, since this assertion itself is a claim about the nature of reality.
In addition to the error I've just pointed out (MDR does not state that "nothing at all can conform to reality"), Steven errs here in another way: when MDR states that our concept of reality is based upon distinct and overlapping models that successfully explain and predict data, it is not a statement about reality — it is a statement about the nature of models.

The claim that we do not have a model-independent description of reality is an inductively derived, provisional assumption that follows from two foundational assumptions: I exist, and my sensory data is sometimes correct. We can gleam the truth of this assumption from inconsistencies and errors in our phenomenological experience, our difficulty in communicating what we perceive as truths to others, and in the failed predictions or superfluous assumptions of misguided theories. If we had a model-independent concept of reality, we would never misperceive it or make cognitive errors. Indeed the entire enterprise of science would be unnecessary, since there would be no need to account for data or make predictions — our intuitions about reality would be 100% correct, 100% of the time. All human knowledge could be subsumed under a singular school of analytic philosophy, because our process of reasoning would always correspond correctly to reality.

Steven drops a sarcastic bombshell here that leaves me utterly guffawed:
The point is that MDR essentially claims the following: No model or theory is real, except, you know, the theory of MDR.
 MDR is neither a theory or a model. It is a provisional epistemological assumption about the nature of human cognition.

Steven appears equally hung up in misguided incredulity over the way MDR treats the concept of 'real', and trots out an example that I remember William Lane Craig using, and I remember feeling equally dismayed at how utterly badly he understood Hawking. Steven states,
On the contrary, I maintain that Mike has misunderstood MDR here. For when Hawking was discussing his theory that one model cannot be more real than another, he uses a very specific and revealing example—namely, that of creationism and the Big Bang theory. Examine this quote straight from the horse’s mouth: “this model—the big bang theory—is more useful than [creationism]. Still, neither model can be said to be more real than the other.” Did you catch that? The big bang cannot be said to be more real than creationism! Herein lies the absurdity of MDR. Again, remember that Hawking is not claiming that we can’t determine which theory accurately conforms to reality, rather neither theory conforms to reality at all, since conformity with reality is meaningless.
Like Craig, Steven is failing to distinguish between colloquial and philosophical usage of the concept of real (ironic for a couple of guys who confidently tout their expertise in philosophy, no?). MDR in no way prevents us from saying "the model presented by young-earth creationism is not real" in the ordinary, everyday sense we use the word 'real' — because, as Lakoff pointed out in the examples of cognitive neuroscience I highlighted in my previous post or as Sean Carroll points out in his post about the reality of free will, that use of the word conveys an ontology necessary to explain our experiences from a certain frame of reference (in this case, our everyday phenomenological frame of reference).

Hawking is saying that fundamentally, the concept of real is only analogous and emergent — a construct of the mind. We call things 'real' when they contain a theoretical ontology necessary to account for data and make predictions. The field of computational neuroscience, for example, is based on a semantic framework that is entirely metaphorical: the Brain As Computer metaphor. There are not literally numbers being crunched the brain, but the metaphor is absolutely essential to our understanding of how the brain works. This is what is meant in saying that because the computational metaphor contains a necessary ontology for explaining and predicting phenomena, we ascribe to it the quality of 'real'.

But I want to go a step further in my critique of Steven here. I think he's attempting to sustain his criticism of Hawking and his incredulous rejection of MDR by adopting an interpretation of Hawking's work that is so unapologetically uncharitable that it borders on complete absurdity. If Steven's view of Hawking's work were correct, Hawking would be openly — not even tacitly! — claiming that reality is whatever we prefer it to be, and that we can adopt whatever scientific explanations we choose to describe the world. Steven is taking Hawking's use of the word real as a colloquial synonym for words like true and valid, when Hawking is using it in a highly specific philosophical context. For Hawking to adopt the view Steven has ascribed to him would mean for Hawking to be disregarding his entire career of theoretical work for a naive refrain of "Hey man, reality is whatever you want it to be". Steven is entitled to think (mistakenly, in my estimation) that Hawking lacks the philosophical sophistication of his Scholastic heroes. But does he really take Hawking to be that stupid?

Steven then returns to solipsism and realism:
[On] MDR neither realism nor solipsism is true, or false. In fact, such talk is, on MDR, superfluous. But this, again, is where the absurdity lies. For either a reality exists apart from subjective observers, or it doesn’t. This pure logic: either A or not-A. What we cannot say is “neither.”
This dichotomy is true, and indeed MDR does affirm the existence of an external reality — though it is an inductive and provisional assumption, not a claim of a priori truth as in the case of metaphysical realism (Steven's repeated oversight of this fundamental distinction again betrays a lack of nuance in his critiques) . But while we can say that ontologically one or the other must be the case, we can also rightly point out that epistemologically, it is a useless and superfluous discussion — which is precisely what follows from MDR.

Steven then shoots one so far over the bow that I can't even feel it breeze by:
For the main point of Mike’s post is an attempt to demonstrate that I have misunderstood MDR, and that my attacks against it are invalid. But wait. How, on MDR can Mike say that any “model” one espouses, whether mine or anyone else’s, is incorrect? He can’t. Remember Hawking: “it is pointless to ask whether a model is real[.]” Talk of real, unreal, true, or false, is meaningless here.
Again Steven is hastily and erronously conflating a colloquial usage of the word 'real' as a synonym for 'true' or 'valid' and uncharitably butchering Hawking's highly contextual intended meaning.  On MDR, models that have lesser (or zero) ability to account for data and make predictions are discarded as more reliable models form a coherent picture from convergent evidence in multiple frames of reference. Hawking is clear on this issue even in the full quote of the section Steven quotes above (emphasis mine): "According to model-dependent realism, it is pointless to ask whether a model is real, only whether it agrees with observation." Nothing stops us from saying that unreliable models of reality are 'not real' in our everyday parlance — creation 'science', such as it is, clearly does not agree with observation. Hawking's point is that the concept of real is ascribed to successful models rather than being a fundamental part of their ontology.

Steven closes his argument:
Mike, again, seems to miss the blatant contradictory nature of MDR here. He, and Hawking, claim that we do not have a model-independent concept of reality, and that we can only find utility in models, not truth or reality in them. But this itself is a claim about the nature of reality. Just ask the question “Is it really the case that we have no model-independent picture of reality?” The answer will commit one to make an objective claim about reality.

MDR does not claim we cannot find "truth or reality" in models — it claims (I'm repeating myself here) that our very concept of reality is derived from models. This is not a claim about reality; it is a claim about our epistemological relationship to the world, and it is the only such claim that is consistent with our empirical knowledge of the human mind while making a minimum of assumptions.

Steven closes by asserting that MDR "remains an incoherent, absurd, and self-refuting philosophic position". But Steven has only been able to sustain his criticism by constructing a caricature of the concept and displaying a wanton disregard for charity in reading Hawking's work, butchering Hawking's words into something barely recognizable from the nuanced and contextual concepts he put forth in The Grand Design.

The supreme irony here is that what Steven accuses MDR of doing is precisely what he hopes to do in undermining it. MDR tells us how we frame ideas and test them, slowly constructing a layered, composite conceptualization of reality through overlapping theories from a variety of reference frames. In rejecting MDR, Steven can claim to have a model-independent, privileged access to deep ontological truths that are free from the burden of testing and falsification. He becomes free to believe in whatever he wants — after all, if you want to shoehorn a deity into your picture of reality, a parsimonious and empirically responsible philosophy like model-dependent realism (and with it, Lakoff's embodied realism) will quickly disabuse you of such a fantasy. Given his theistic bent, is Steven's incredulity really surprising?

12 November 2014

Is Model-Dependent Realism "self-refuting"?

Recent comments have prompted me to revisit an old post from semi-regular commenter Steven Jake, from his own blog The Christian Agnostic — which I have to say, despite our constant state of disagreement, I generally find to be one of the more thought-provoking religious blogs I've read.

A couple of posts back, I described myself as a non-eliminative physicalist — that I'm a physicalist because I do not believe in mystic or supernatural forces, and I believe that all phenomena in the known universe, including our consciousness, ultimately terminate in physical forms. But I'm non-eliminative because I believe that there are different levels of description of reality — that different models of reality with different semantic and theoretical frameworks can overlap, and can be equally 'real'.

This came from my relatively recent re-reading of George Lakoff's Philosophy in the Flesh (it's really long and very technical in parts, so you definitely pick up lots of stuff on a second or third pass). Lakoff draws some examples from neuroscience (he is a cognitive linguist) to illustrate his point:
We have seen that reality and truth occur relative to our understanding at many levels and from many perspectives. This is inconsistent with the classical eliminativist program in the philosophy of science, which asserts that the only realities and the only truths are at the "lowest level," here the neural level, that is, the level of neurochemistry and cellular physiology.
Virtually no neuroscientists hold this position, as can be seen by the ubiquity of the Neural Computation metaphor. Strictly speaking, "neural circuits" with their neural computational numerical algorithms are not a direct part of neurochemistry and cellular physiology, which talks about such things as ion channels, neurotransmitters, and cell permeability. But the Neural Computation metaphor, which defines the field of computational neuroscience (linking the middle level to the bottom level in the common paradigm), is absolutely necessary to an adequate understanding of how the brain and body function. No serious neuroscience could "eliminate" these higher, metaphorically constituted levels of scientific understanding at which computations using numbers are taken as real.
The same is true of the models of linguistic and cognitive behavior constructed by cognitive linguists and other cognitive scientists, for example, structures like conceptual systems and theoretical constructs such as basic-level categories, conceptual metaphors, image schemas, and prototypes. When there is sufficient convergent evidence, such theoretical constructs are taken as "real." Since we are not, and could not be, aware of them, they are postulated as part of the cognitive unconscious. What we call "the cognitive unconscious" is the totality of those theoretical cognitive mechanisms above the neural level that we have sufficient evidence for, but that we do not have conscious access to. Like each of the cognitive mechanisms that constitute it, the cognitive unconscious as a whole, as a general phenomenon, is taken to be real.

The term model-dependent realism didn't come around until many years later when Stephen Hawking wrote The Grand Design, but I think Hawking and Lakoff would find themselves in much agreement. MDR is a non-eliminative physicalist position, and squares very well with Lakoff's embodied realism. Take some of Hawking's quotes on MDR:
[Model-dependent realism] is based on the idea that our brains interpret the input from our sensory organs by making a model of the world. When such a model is successful at explaining events, we tend to attribute to it, and to the elements and concepts that constitute it, the quality of reality or absolute truth.
According to model-dependent realism, it is pointless to ask whether a model is real, only whether it agrees with observation. If there are two models that both agree with observation ... then one cannot say that one is more real than another. One can use whichever model is more convenient in the situation under consideration. 
[...] our brains interpret the input from our sensory organs by making a model of the outside world. We form mental concepts of our home, trees, other people, the electricity that flows from wall sockets, atoms, molecules, and other universes. These mental concepts are the only reality we can know. There is no model-independent test of reality.

There's clearly a great deal of commonality between Lakoff and Hawking's theses. Personally, I've found these types of epistemological frameworks exceptionally reasonable and parsimonious. It seems to me that the only way one could deny these models is to claim that you have a privileged epistemological access to reality not afforded to the rest of humanity, that the very idea of modeling and testing reality is misguided — and the entirety of scientific truth along with it. 


Steven Jake, however, has a much less charitable view. Just a few quotes from his post on the subject:
Frankly, I get quite tired of having this idea thrown around when it is so blatantly ridiculous, and thus I felt the need to demonstrate such.
It should be obvious upon first glance how extreme and ridiculous MDR is.
This is pure nonsense.
To illustrate the depravity of such a position....
Yeah…this is the intelligence blooming from the mind of Hawking, and this is why Einstein said, “the man of science is a poor philosopher”. 
I personally find it ridiculous, and therefore, not pragmatic, to hold to MDR

Let's cut through the rather thick layer of dismissive snark in this harangue and see what constructive criticisms Steven really has to offer:
[MDR] is an amalgam of previously known philosophical positions such as pragmatism, constructive empiricism, and some type of idealism—all, at least to me, untenable philosophies in themselves.
Not quite. MDR, and with it Lakoff's embodied realism (which I'm subsuming under MDR for the sake of this discussion), certainly take several important points of view from a variety of older analytic philosophies. But they also summarily reject many of the tenets these philosophies espouse, and it's important to recognize those distinctions. For his part, Lakoff's work is much more focused on dissecting various viewpoints of analytic and postmodern philosophy, and articulating why in his view they are inconsistent with empirical evidence for the cognitive structure of the embodied mind. Hawking, by contrast, doesn't spend too much time musing over philosophical positions since his book is primarily about speculative physics. I think then that Lakoff's work is probably a better choice for someone interested in contrasting an MDR-like epistemology with classical philosophy, though I don't think that excuses hasty dismissal of Hawking's proposition.

Steven continues,
First, let it be understood that MDR does not claim that if two theories can both accurately describe or predict the same observations, then we cannot, at the moment, determine which theory actually conforms to objective reality. No, MDR is claiming that neither theory conforms to reality more than the other—that is, neither theory is more real than the other.
MDR does not claim that models "conform to reality" at all; it summarily rejects the idea of an absolute reality to which we have unfettered access — this means we cannot, in principle, know whether a model "conforms to reality". Rather, it claims that our very concept of what reality is is contingent upon our ability to construct models and test them against observation.We assign the term "real" to concepts that allow us to successfully model and predict the world around us. This is quite similar to what Lakoff states (emphasis mine):
In an eliminative physicalist theory, explanation would flow in one direction only, bottom to top, with only the neurobiology taken as real and the other levels taken as epiphenomena.
This is not the case in the [Neural Theory of Language] paradigm. The paradigm is physicalist in that it does not claim that any mystical nonphysical entities such as soul, or spirit, or a disembodied Cartesian mind exist. Ultimately, the brain is all neurochemistry and neurophysiology. But it is noneliminative in two ways. First, each level is taken as real, as having a theoretical ontology necessary to explain phenomena. Second, explanation and motivation flow in both directions. To explain how the neurochemistry and neurophysiology function in networks of neurons, we need a theoretical level of neural computation. Explanation of what the physical neurons are doing flows from the middle level to the bottom level. This is a noneliminative, top-to-bottom form of explanation.
Steven has fundamentally misunderstood what MDR means in saying that no model can be said to be more 'real' than any other; it is simply saying that different 'frames of reference', such as the neural and cognitive models of the mind, overlap and converge to form our picture of reality, even though they may in some ways be semantically or theoretically incompatible (that is, no one frame of reference can fully explain all phenomena). Our confidence in what we call 'real' increases as evidence from those multiple frames of reference forms a composite picture from compatible yet distinct models.

Lakoff's neural examples are great, and an evolutionary one is great as well: our confidence in the reality of evolution is based on convergent evidence from geology, paleontology, molecular biology, and genetics. These fields use disparate methodologies with distinct semantic and theoretical frameworks, but create an overlapping and compatible picture which — because it is highly improbable that so many independent models could all be wrong — increases our confidence in the reality of evolution. Yet you cannot talk about paleontology using the semantic and theoretical framework of molecular genetics; each model requires its own unique paradigms, and we can coherently describe them both as 'real' because they both possess a theoretical ontology necessary to explain observed phenomena.

Steven continues, contrasting MDR with some well-known philosophical positions:
The realist states that an objective reality exists independent of observers, while the solipsist states that only his mind exists. Surely these models are mutually exclusive, and either one or the other has to be predicated of reality—that is, either only I exist, or a reality exists which I am a part of; there is no middle ground here. However, on MDR we cannot say that one is true while the other is false. Rather, neither is true.
MDR would say that both classical realism and solipsism (specifically, ontological solipsism) make fundamentally untenable assumptions. We do not have unfettered access to an ultimate absolute reality, and we have ample reason to assume, based on evidence arrived at through induction, that a reality external to our minds does in fact exist. MDR does not summarily declare either position false, as Steven asserts; rather, neither can be said to be true or false.

Steven then claims that MDR leads to the "rejection of itself" through pragmatism:
Remember that MDR asserts that if two models of reality are equally on par at describing our observations, then we can use whichever model we find most valuable or convenient. This is pure pragmatism—and MDR, just like any philosophy founded on pragmatism, runs into problems because of this. First, if one can adopt any model based on its utility, then the validity of models is subject to the whims of individuals. For what’s pragmatic for me will not necessarily be pragmatic for you.
Steven has begun here with a bit of a straw-man argument. Let's look again at what Hawking said:
If there are two models that both agree with observation ... then one cannot say that one is more real than another. One can use whichever model is more convenient in the situation under consideration.
Now pragmatism in philosophy is, according to the IEP, "a philosophical movement that includes those who claim that an ideology or proposition is true if it works satisfactorily, that the meaning of a proposition is to be found in the practical consequences of accepting it, and that unpractical ideas are to be rejected." What Hawking is talking about here has absolutely nothing to do with philosophical pragmatism.

The first clue is that Hawking describes a scenario in which two or more models as agree equally with observation, and in doing so has set up an important condition that prevents us from having a choose-your-model free for all. Lakoff's neural paradigm provides a fine example. The neurobiological, neurocomputational, and cognitive models of the mind all agree strongly with observation. But it's impractical for the neurobiologist to use a cognitive model of the mind, because it requires a completely different semantic and theoretical structure. For a physicist, it's entirely possible (in principle, at least) to calculate the trajectory of a baseball pitch using quantum mechanics. But given the extraordinary amount of data that would be required, it's much more practical to simply use Newton's laws of motion. Both quantum mechanics and Newton's laws agree strongly with observation, but physicists can take pragmatic concerns into account when deciding which frame of reference to use. That measured, contextual distinction is what Hawking is describing — not the ridiculous position Steven has erroneously attributed to him.

Mistakenly thinking he's scored a decisive rebuttal, Steven continues:
Pragmatism is a theory of truth which explicitly rejects the correspondence theory of truth—i.e., a statement is true if it corresponds to reality. But, the only way to do this is to make an objective claim about reality—that is, truth as such is illusory.
Steven's already wrong in claiming that MDR is a pragmatist epistemology; but now he's doing something that would make most academic philosophers cringe in claiming that it's in principle impossible to reject the correspondence theory of truth without making an objective claim about reality itself. The correspondence theory of truth, however, is not the golden child of philosophy; philosophers have long posited a number of objections to it.  The correspondence theory is epistemic, not ontological, and so is its rejection. And where the correspondence theory most finds itself in trouble is precisely in the notion that we have unfettered access to an absolute reality — that the concepts of the mind correspond directly with the world. Lakoff has identified three gaps in analytic philosophy that the correspondence theory has to overcome:
Gap 1: The gap between the natural language and the symbols in a "formal language" that are used to represent aspects of the natural language.
Gap 2: The gap between the symbols of the formal language and the sets of arbitrary abstract entities in the set-theoretical model of the language.
Gap 3: The gap between the set-theoretical models of the world and the world itself.
This is beyond the scope of this post, but suffice to say that 1) a great many philosophers have objected to the correspondence theory for a variety of reasons, and 2) MDR has nothing to do with philosophical pragmatism.

Steven wraps up,
Advocates of MDR seem to make their case solely on the basis of how our sensory organs take in datum and relay it to our brain. This seems, to them, to demonstrate that only the appearance of reality is accessible to us, as opposed to reality in itself. But, notice that this is once again an objective claim regarding what really goes on when we abstract concepts from the observed. More importantly there are many epistemologies out there that take such cognitive facts into account while still proclaiming that reality in itself can be known. 
Steven's gotten all the way to the end of his post without grasping the most important point: MDR renders meaningless the distinction between "reality accessible to us" and "reality in itself". Of course most philosophers and scientists (including Hawking) operate on the provisional, inductively-derived assumption that an absolute reality does exist. But we do not have an unfettered, privileged access to such a reality in which one level of explanation (or one 'frame of reference') successfully describes all phenomena. Rather, our picture of reality is a collage of convergent and overlapping models whose success and applicability is contextual and specific.

So has Steven successfully dismantled model-dependent realism? I don't believe so. In my estimation, he's only succeeding in betraying his hasty, uncritical dismissal of an idea to which he is personally incredulous. 

Would you recognize yourself in Heaven?

One of the great insights of modern neuroscience is the way that our phenomenological experience can be profoundly and counter-intuitively altered when various regions of the brain do not function properly. You can lose the ability to feel empathy; or, you can retain the ability to feel empathy but lose the intuition for reciprocation (i.e., empathetic behaviors). You can lose the ability to recognize faces, or forget the names of people but remember the names of tools. Your personality can be dramatically altered by variations in your neural composition.

The reason this is counter-intuitive is because we tend to view our personalities, and those of others, as fixed. I am who I am, and that's just the way it is. Joe is the way Joe is, Jane is the way Jane is. If Joe suffers from pathological narcissism or Down's Syndrome, that's just the way Joe is. If Jane is exceptionally compassionate and selfless, that's just the way Jane is.

People do recognize that life experience plays a crucial role in shaping our personalities, but we tend to underestimate just how much our biology factors into the picture. Humans are no different from animals in that our temperament is powerfully influenced by our biology, as are our moods, emotions, and our ability to think critically.

So what if consciousness is not what the brain does, as a non-eliminative physicalist like yours truly would view it, but rather consciousness is ultimately disembodied and merely runs on the brain like software — and, in our bodily death, our consciousness will somehow rise off the brain and we will experience some sort of new, non-physical reality?

A substance dualist would take the view that when the personality of an individual is irreparably altered by trauma to the brain, the 'true' personality of the person still exists — it simply is not being fully realized because the brain is not functioning properly. But this raises an interesting conundrum for a blissful spiritual afterlife (which, as I've argued many times, is already littered with logical and conceptual problems [1], [2], [3], [4]): who would we actually be in Heaven? Would we recognize ourselves, or others?

If, for example, we take Joe the pathological narcissist, he might be kind of asshole through little fault of his own. He is literally unable to feel empathy the way the rest of us do; his moral and social behaviors are based purely on utilitarian considerations. And, as humans, we tend to see this as fixed. So, will Joe be cured of his narcissism in Heaven (assuming narcissists can attain salvation), since his consciousness is now untethered from his abnormally-functioning brain? If Joe has Down's Syndrome instead, will he no longer be recognizable as the disabled individual he spent his whole life being?

I suspect many believers would want to answer in the affirmative, but doing so only complicates the issue. What about Jane, who is ultra-compassionate? Jane, like a rare few, has an exceptionally high level of empathy. Her brain functions abnormally, but it makes her an exceptionally loving, selfless person — a model Christian, one might say. When her consciousness is untethered, does her personality revert to somewhere in what we would consider the 'normal' spectrum of brain function?

Consider also those who, through accidental brain trauma, have achieve some extraordinary new skill — like Jason Padgett, who gained the ability to perceive the world as complex equations and draw those equations by hand in exquisitely detailed form. Will he lose such an ability in Heaven, or will the rest of us gain it? Will musical savants become normal, or will we all become musical savants?

The problem dualism faces here is that when the consciousness is no longer tied to the brain, it's impossible to predict what the consciousness will actually be. Components of our personality that we take to be fixed and central to our personal and social identities, no longer being dictated by the composition of the brain, could change drastically or be gone altogether. Dualists don't know; they can only conjecture.

In what sense, then, is your disembodied consciousness really "you" at all? Not only could your personality and the personalities of those around you be altered such that they bear little resemblance to their embodied form, but even your language and your process of reasoning — which are shaped powerfully by your embodiment — will be necessarily altered such that they bear little resemblance to the version of you that exists here on Earth.

In my experience, believers tend to view the afterlife as essentially a continuation of their Earthly experience, perhaps enhanced in some way but fundamentally preserving their memories and personalities. But the fact of our embodied mind and the way in which our neurology is so centrally tied to our behavior show that if you were indeed a disembodied consciousness, you would bear so little resemblance to your Earthly self that it's not coherent to even call the afterlife a continuation of your embodied phenomenological experience. It seems that even if you believe you have an immortal soul, your Earthly personality would still be left behind with your corpse.

09 November 2014

Non-eliminative physicalism and model-dependent realism (and cake!)

Discussions about philosophy can be exasperating; they're often steeped in esoteric language and can seem pedantic. After all, philosophy isn't something we concern ourselves in our daily lives; we have intuitive, functional ways of going about our day that we adopt without so much as a second thought, and at first blush it seems like philosophy doesn't have much hope of changing much about the human experience. And I suppose that directly, that's true. All my years of reading and discussing philosophy certainly haven't changed much, if anything, about how I live my life on a day to day basis. But it has informed how I think, how I shape and define my beliefs, and how I communicate my ideas with others.

If that seems like an odd way to start a post with an admittedly esoteric and verbose title (I really had no idea how to make it catchy), it's because I can fully understand why someone would look at these topics with a big fat Who gives a shit? Why should you care about eliminative vs. non-eliminative physicalism? What the hell is model-dependent realism? Why should you care about ontology? Well, I can't promise that reading about this stuff will change your life. It probably won't make you a better person. But it might give you a new perspective on how we approach the acquisition of human knowledge, how we can identify erroneous ways of thinking, and what types of beliefs are justified. Because this is a lengthier-than-usual post, I've stuck in the dashes to break it up a bit.


The correspondence theory of truth
To get to non-eliminative physicalism, I'm going to start with Aristotle, the godfather of essentialism. For Aristotle, there was no distinction between epistemology (how you know what you think you know) and ontology (what things actually are). He contended that our minds directly grasp the "essences" of things in the world, so there is no bridge between conceptual abstraction in the mind and objective truth in the world. If I say, "the cat is on the mat", I am thinking about objectively real things that have distinct categorical identities that exist objectively — that is, independently of my mind. All that is required of the mind is to grasp what is, and to even contemplate the idea of the cat on the mat is to recognize that the cat and the mat both have distinct categorical identities. In this view, the mind is not modeling the world, but simply recognizing it — the categories of the mind directly correspond to the categories of the world.

This essentialism can also be considered the roots of what is popularly called the correspondence theory of truth [1]. Put in its most simple and colloquial form, the correspondence theory simply says: 
A statement is true when it fits the way things are in the world. It is false when it fails to fit the way things are in the world. [Lakoff, Philosophy in the Flesh]
This seems intuitively obvious, and the old "cat on the mat" example shows why. Most of us agree that if we are observing a cat on a mat, we are observing objects that are distinct from each other and that exist independently of our ability to perceive them. The cat has distinct cat-making properties, just as the mat has distinct mat-making properties. Moreover, we recognize "on-ness", or the state of the cat being on the mat, as being an objectively true statement about the relationship between these two objects. If I say "the cat is on the mat" while the cat is in his litter box, my statement is objectively false because my expression of the relationship between those two objects does not correspond to the way things are in the world.

Aristotle took all this a step further. While we all agree about the properties and relations of physical things like cats and mats, conceptual abstractions like "love", "truth", and "being" might seem to have a more ambiguous nature. Love is clearly not a physical thing, but most of us agree that in some sense love exists. Aristotle thought that these types of abstractions were simply different categories of being: non-physical and immaterial, but nonetheless wholly real in that distinct properties could be predicated of them. When we contemplate love, we are contemplating something non-physical but something that still has real properties (or an "essence") that our minds are simply recognizing. Love is not a construct of the mind, but a real non-physical entity in the world that the mind grasps through reason.

It might be hard to imagine why the correspondence theory of truth is loaded with some serious problems when it seems to reflect exactly how we interact with the world and know things to be true or false in a highly intuitive way. But a closer examination reveals that the correspondence theory not only leaves crucial questions unanswered, but also fails to conform to our empirical knowledge of how the mind actually works.


The elephant in the room for the correspondence theory is how the mind grasps and expresses these relationships. According to the Aristotlean view, the mind — and reason itself — is ultimately disembodied, in that the body plays no crucial role in the formation of concepts. But this leaves us without any explanation as to how the non-physical mind is able to bridge the gap to physical objects, spatial relationships, and non-physical abstractions. Aristotle's solution is a "just-so" argument, in which the problem is wholly ignored altogether: the mind recognizes these distinct objects and relationships because it does. How is never even broached.

To see why this is problematic, I want to re-visit something I talked about in an older post: the existence of "color". According to the Aristotlean view, if I say "the painting is blue", I am expressing "blue" as an objective property of the painting. The same is true if I say that "the sky is blue". However, this conflicts with our empirical knowledge of the world. Waves of light, in themselves, do not have the property of color. We perceive color because of an interaction between the cones in our eyes and neural structures in our brains. To understand this, consider the painting and the sky both having the property of "blueness". The sky is not a solid object; it appears blue because certain wavelengths of visible light are scattered by our atmosphere. This is starkly different from why the painting is blue, which is because light is being reflected off a solid object. Moreover, whether the painting appears blue is also contingent on the wavelengths of light the object absorbs or reflects, like how an object may appear either green or blue depending on the ambient light. The correspondence theory is in trouble on both fronts: both in its inability to bridge the gap between the non-physical mind and the physical world, and in its erroneous attribution of "blueness" as an inherent property of an object.


It gets worse, though: there are levels of "truth" which appear to be incompatible with one another. The Aristotlean view privileges a certain frame of reference: the phenomenological — that is, our everyday conscious experiences and intuitions. But as the color example demonstrates, this cannot be true.

In the phenomenological view favored by essentialism, color is a property inherent to an object. In this sense, the notion of "the painting is blue" seems intuitively true: the property of blueness is inherent to the painting. But given what we know about what color is — the aforementioned interaction between the visible electromagnetic spectrum, light cones in our eyes, and neural structures in the brain — the similar statement "the sky is blue" cannot be true. The sky is not an object, and thus cannot have an inherent property of blueness. Rather, the concept of blue must be modeled by our brains through the interaction of our embodied minds and visual cortex with the physical world.

So we have two views: a scientific, physical view that describes color as wavelengths of the electromagnetic spectrum interacting with our visual cortex; and a phenomenological view that describes color as an inherent property of objects. On the correspondence view, both cannot be true because the correspondence theory calls for a unified truth that holds at all frames of reference.


Abstract thought and metaphor

Let's jump ship for a bit and talk about love; or rather, conceptual abstractions like love. Remember that on the correspondence view, love is a real but non-physical thing which our minds comprehend through pure reason — the body and brain play no role in constructing the concept of love. 

It's worth repeating that this view fails to show, just as it did with objective physical objects and relations, how the mind recognizes these objective non-physical objects and their relations. If love is "out there" in the world simply waiting to be discovered through a disembodied process of reasoning, how does this process of discovery occur? How is the gulf between perception and existence bridged by the mind? The Aristotlean view again leaves us no answer.

But as with physical things, the problem is worse for the correspondence view with non-physical things as well. If our concept of love is a correspondence to a literally real non-physical thing, then we ought to be able to identify a definition of love that is true independently of any frame of reference. Again though, we have a scientific view of love — neural and chemical structures in the brain, responses to stimuli, and metaphorical thought — and a phenomenological view of love. Both are useful frames of reference in certain contexts, but both cannot be true under the correspondence theory of truth.

A hasty reaction would be to claim that the physical processes associated with love are merely physical correlates resulting from our embodiment, and not the formation of love itself. But we cannot even conceptualize love without using metaphorical language. Take the old Biblical scripture from 1 Corinthians:
Love is patient, love is kind. It does not envy, it does not boast, it is not proud. It does not dishonor others, it is not self-seeking, it is not easily angered, it keeps no record of wrongs. Love does not delight in evil but rejoices with the truth. It always protects, always trusts, always hopes, always perseveres.
The word is expresses a relationship meaning equal to. So if I am behaving patiently while waiting in a traffic jam (calmly listening to music instead of, say, honking my horn and yelling at strangers), does that imply that I am behaving lovingly? For most of us, love is a deeper and more complex concept than that. We associate love with some measure of selflessness, generosity, and humility. The Biblical scripture is discussing love in metaphorical terms (in this case, as an entity or force), because that is the only way love can be discussed at all.


Frans de Waal, in a popular TED Talk, discussed (as he often does) the empathetic behavior of apes. He explained that empathy can be divided into two broad categories: a physical channel and a cognitive channel. The former is when, if for example we're consoling a grieving friend, we adopt the posture and body language that they do. This type of mimicry is common in our modern evolutionary cousins. The cognitive channel is the process of imagining ourselves in the others' place, in a sense 'feeling what they feel'. This, it appears, animals have not developed as we have.

Consider how George Lakoff, in discussing the work of Christopher Johnson, relates a similar concept to the development of abstract concepts in humans:
For example, for an infant, the subjective experience of affection is typically correlated with the sensory experience of warmth, the warmth of being held. During the period of conflation, associations are automatically built up between the two domains. Later, during a period of differentiation, children are then able to separate out the domains, but the cross-domain associations persist. These persisting associations are the mappings of conceptual metaphor that will lead the same infant, later in life, to speak of "a warm smile," "a big problem," and "a close friend."¹
It appears that many animals (who, not coincidentally, have in some cases the intelligence of a three-year-old human child) never develop this abstract domain in conceptualizing love, but are able to develop an undifferentiated concept that we might call "love". But notice that even after differentiation occurs in humans, we must still describe love using those metaphorical terms.

If love were an objective non-physical entity that a disembodied process of reasoning simply corresponds to, then we ought to be able to divorce love from the metaphorical language that arises through our embodiment. But, imagine a statement like this:
George loves his wife. He's never felt close to her, he's always put his own needs ahead of hers, and he has always responded to her gestures of affection by withdrawing from her even further.
In what sense does George love his wife? The first sentence seems completely divorced from the second, because those metaphors do not comport with those we use to describe love. Can we describe what it means for George to love his wife without using metaphorical language that is the converse of the above?

Notice too that the metaphors express spatiotemporal relationships. A loving relationship is one in which the partners feel "close"; cold-hearted George is putting his needs "ahead of" his wife's. These metaphors are essential to our description of complex concepts like love, but make no sense if reason could be divorced from our embodiment. 


We've seen how the Aristotlean view fails. It fails to give us an account of how the mind interacts with the world to perceive correspondence, it fails to take into account multiple frames of reference, and it fails to provide a basis for metaphorical thought.  So what view could we adopt instead?

Model-dependent realism and physicalism

All of the difficulties with the Aristotlean view disappear if we adopt model-dependent realism, a concept introduced by Stephen Hawking: the idea that there is no model-independent view of reality. Reality, as humans know it, is a construct created through the interaction of the physical world with the gestalt perception of our sensorimotor system and (in turn) the neural structures in our brains. If an objective, perception-independent reality exists, we do not have access to it. Metaphorical language follows from gestalt sensorimotor perception ("that went over my head"), and cognitive abstractions like "love" form from metaphorical thought that arises through differentiated physical experiences.

Those who subscribe to the antiquated Aristotlean view find model-dependent realism highly discomforting. They object that it appears to negate our ability to establish stable truths, since, as Hawking describes in The Grand Design (the book in which he coined the term), no one model is less "real" than any other; instead, what matters is how well the model accounts for known data and allows us to make predictions. Instead of one grand, unified model of the entire universe, we employ a broad range of models that are valid at different frames of reference.

Take again the idea of color. According to the phenomenological frame of reference, the statement "The sky is blue" is objectively true. It reflects a common way in which humans conceptualize color, as well as the way in which we project artificial boundaries onto the world and treat spaces like container-objects (e.g., "the plane is in the sky"). An eliminative physicalist view would say that this is false — there is no "blue" in the sky; all that exists are wavelengths and neural structures. But this viewpoint fails to adequately account for how we conceptualize color and integrate the concept into our language and experience. It is bankrupt for the same reason that the Aristotlean view, with its singular focus on the phenomenological frame of reference, is bankrupt.

Model-dependent realism, then, is a form of what is called non-eliminative physicalism. It is "physicalist" in that it provisionally assumes that all things are ultimately underscored by a physical reality; it posits no mystical entities or undetectable supernatural forces to explain the universe or our interaction with it. But we call something "real" if it accounts for known data and allows us to make predictions; on that view, the term "the sky is blue" is true, because our phenomenological model provides a frame of reference in which it is a meaningful and valid statement.

One of my all-time favorite essays was Sean Carroll's blog post "Free Will Is as Real as Baseball". Without using the term, Carroll is in fact adopting model-dependent realism:
We talk about the world using different levels of description, appropriate to the question of interest. Some levels might be thought of as “fundamental” and others as “emergent,” but they are all there. Does baseball exist? It’s nowhere to be found in the Standard Model of particle physics. But any definition of “exist” that can’t find room for baseball seems overly narrow to me. It’s true that we could take any particular example of a baseball game and choose to describe it by listing the exact quantum state of each elementary particle contained in the players and the bat and ball and the field etc. But why in the world would anyone think that is a good idea? The concept of baseball is emergent rather than fundamental, but it’s no less real for all of that.
Likewise for free will. We can be perfectly orthodox materialists and yet believe in free will, if what we mean by that is that there is a level of description that is useful in certain contexts and that includes “autonomous agents with free will” as crucial ingredients.

Carroll is acknowledging that there is a certain frame of reference in which the idea of "free will" makes no sense. There is no room for some sort of "contra-causal" free will in any of the known laws of physics. But there is another frame of reference — our phenomenological one — in which viewing ourselves as rational agents capable of choosing is both valid and necessary. "Free will", in that sense, is as real as any other facet of the human experience.


But with all these overlapping frames of reference and models of reality that are contingent upon the available evidence, how can we form stable knowledge? The answer lies in our embodiment. Because we are all human beings sharing a similar biological makeup, we conceptualize the world in similar ways — our shared biology is what allows us to communicate shared concepts and metaphors, creating the possibility for shared, stable truths. 

Further, we can make use of convergent models that employ different methodologies to account for data but yield compatible results. It's highly improbable, for example, that we'll discover that atoms and molecules do not actually exist since they are employed across a wide range of empirical disciplines that have yielded mountains of valid predictions. The phylogenetic tree at the center of the theory of evolution is likewise supported by multiple independent methods of inquiry: geology, molecular biology, genetics, and paleontology (to name a few). It is highly improbable that all of these lines of evidence can converge and yet still be false, and this gives us confidence in the validity of evolution as a stable truth.

Model-dependent realism gives us the best of both worlds: we can have stable truths and accept that there is a reality which exists independently of our ability to perceive it. We can acknowledge many of the phenomenological experiences central to our humanity as real and valid, while also acknowledging the physical structure that provides the basis for it. We can account for metaphorical thought and language, make sense of abstractions, and close the Aristotlean gap between the mind and the world. 


So, why is all this important, anyway? I mean, this post was all kinds of tl;dr, and it was still only a cursory overview of many of these topics. There are complex modern analytical discussions of the correspondence theory of truth which attempt to address the gaps, debates about the formation of metaphor and its place within cognition and language, and on and on. But hopefully this lengthy overview, in which I'm more or less simply attempting to elucidate my own point of view, acts as a springboard for you to see how important these issues are and perhaps sparks some inquiry of your own. If you are that adventurous, I hope you'll share your thoughts in the comments below.

Oh, and the cake is a lie.

1. George Lakoff. Philosophy In The Flesh (Kindle Locations 612-615). Kindle Edition.