About Rationally Speaking


Rationally Speaking is a blog maintained by Prof. Massimo Pigliucci, a philosopher at the City University of New York. The blog reflects the Enlightenment figure Marquis de Condorcet's idea of what a public intellectual (yes, we know, that's such a bad word) ought to be: someone who devotes himself to "the tracking down of prejudices in the hiding places where priests, the schools, the government, and all long-established institutions had gathered and protected them." You're welcome. Please notice that the contents of this blog can be reprinted under the standard Creative Commons license.

Tuesday, November 01, 2005

Does empathy negate physicalism?

Tough question. It has been posed (and answered in the positive) by Michael Philips in a recent article in Philosophy Now. Let's see what this is about. Empathy, of course, is the ability that all normal human beings (there are some pathological exceptions, which are actually going to be very relevant in a minute) have of, in some sense, being in someone else's metaphorical shoes. Empathy, in other words, is that mental phenomenon that allows us to at least approximately feel the pain, or pleasure, being experienced by someone else, which in turn allows an understanding of other people's emotional situations.

Physicalism, on the other hand, is a philosophical term that indicates a family of theories about the mind-body relationship (for a rather technical summary see here). In particular, physicalism says that the mind in fact is a result of brain activity, excluding the possibility of any form of mind-body dualism. There are several versions of physicalism, but two major ones are the so-called "type identity" and "token identity" theories. Bear with me for a second, this is going to be interesting once we pass the technicalities.

A physicalist identity theory basically says that there is some correspondence between physical and mental states, i.e. that in order to have a given mental state (say, feeling pain) one has to be in a certain brain state, because the brain is the causal factor behind so-called mental events. If one subscribes to a token identity theory, then one is saying that any particular mental state corresponds to (it's identical with) a specific brain state. Only that brain state will cause that particular sensation or feeling. On the other hand, the more flexible type identity theory says that there is in fact a correspondence between brain states and feelings, but that this may be a many-to-one relationship, i.e. there may be several different configurations of a brain (or equivalent structure) that can generate a certain sensation in the subject. Keep this distinction in mind, it will be useful in a bit.

Philips, and other philosophers of mind, argues that physicalism is incompatible with the existence of empathy, because empathy implies the existence of qualia, and qualia cannot be accounted for by physicalism. Yup, we need to take care of another little bit of technical jargon. Qualia are so-called "secondary" properties of objects. Primary properties are independent of observers, for example shape. A box is a box regardless of who observes it, human or machine. Secondary qualities, however, are in some sense "in" the observer, for example in the case of colors. Yes, colors are elicited by the physical characteristics of light waves, but the experience of seeing a color (qualia are experiences) demands the subjective presence of a conscious being actually having the experience. (One can already object to this that, in fact, plenty of living beings -- for example insects -- experience colors in a physiological sense, and yet are not conscious in anything like the sense of the term when applied to human beings, but let that pass for now.)

Next, to the crux of the matter. Philips argues that empathy is made possible by qualia, because empathy is about feeling that we can experience something very much like what somebody else says she is experiencing (e.g. pain in response to a hammer hitting a finger). But how do we know what it's like to experience, say, pain? It's not because of a physicalist description of pain as a function of brain processes, but rather because we have the capability to experience qualia ourselves. In other words, the argument goes, physicalism may be able to tell us what sort of nerves and nerve impulses are involved in the feeling of pain, but that has nothing to do with the subjective experience of pain. So, physicalism cannot explain qualia; but since qualia are real (as demonstrated by the existence of empathy), then physicalism cannot account for a real (and important) mental phenomenon. Ergo, physicalism must be wrong, or at least grossly incomplete.

Philips' article goes into some detail into the possible responses open to a physicalist, and offers of course a series of counter-rebuttals by Philips. The problem is that one of the fundamental (and unspoken) premises of Philips' whole critique is highly questionable. It turns out that his arguments are pretty good against what I referred to above as "token identity" theory, i.e. the strictest variety of physicalism that claims that there is a one-to-one correspondence between brain and mental states. If that were the case, one could argue that a complete knowledge of brain circuitry would have to be sufficient to account for all mental phenomena, including qualia. But it turns out that subjective experiences are in fact difficult to pinpoint on a specific set of nerves and impulses. This isn't really surprising, because we already know that token identity theories must be wrong. It seems clear that different individuals, with different brains, can have apparently very similar qualitative experiences (such as perceiving colors).

But things get a lot more complicated when one moves to the more sophisticated type identity theory. In this case, the claim is simply that there are classes of brain structures and functions (e.g., nerves and nerve impulses) that can generate mental phenomena. But the same mental phenomena could be generated by different structures and functions, even by entirely different materials (which makes artificial intelligence possible, at least in theory), as long as certain properties are maintained by the system. Think of it as the idea that different types of hardware can run the same sort of software with relevantly similar (though not necessarily identical) results. While if token identity were correct there would be only one way to produce a word processor that looks and works like Microsoft Word, with type identity once can run different pieces of software (e.g., Word, OpenOffice, etc.) on different machines (PCs, Apples) and different operating systems (Windows, Linux), and pretty much get the same "qualia" (i.e., the same user interface) from all of them. If that's the case, type identity is compatible with the existence of empathy.

Finally, remember my initial reference to the fact that normal human beings can feel empathy? It turns out that some brain pathologies, such as the destruction of the amygdalas, make it impossible for a human to feel empathy, because he himself has lost the ability to have emotions altogether. This and similar nightmarish conditions are described in a wonderful book on the human brain, Phantoms in the Brain, by neurobiologist V.S. Ramachandran. What these findings imply, however, is a pretty powerful blow to non-physicalist theories of emotions and feelings: if qualia aren't the result of the activity of certain brain regions (such as the amygdalas), why on earth would people with damage to those regions not be able to experience qualia? This objection is sometimes referred to in philosophy of mind as the "no ectoplasm" clause: we may not know exactly how the brain produces consciousness, but no brain = no consciousness, precisely as a physicalist theory would predict.

Something to ponder, the next time you'll look at the colors of a beautiful sunset...

7 comments:

  1. Massimo, you are too prolific - 10 posts since Friday. I cannot keep up. :)

    Anyway, I thought the brain as the seat of consciousness was pretty much a settled argument these days -- I didn't think there were any credible mind-body dualists out there anymore.

    I have a hard time reading any theories such as the token or identity theories you referenced without thinking they are grossly simplified.

    From what I know about neural networks, I view the brain as a massively parallel analog processor with an immensely complex network of feed forward and feed backward loops in a state of constant flux, making the concept of brain states a weak construct at best.

    I can't imagine that a person has ever had the same brain state twice in their lives (if we consider a brain state as the current state of each of the billions of neurons in a given brain) -- though I'll grant that we have roughly the same brain state for given feelings at certain specific brain circuits or localized neural networks. Indeed, I doubt even recalling a familiar memory, excites exactly the same neurons in the same way as the last time we recalled that memory.

    Therefore, any theories suggesting that empathy cannot exist solely in the physical manifestation of the brain, strikes me as overly simplistic.

    In my view the mind simply emerges as a result of the physical processes of the brain and that includes the ability to be empathetic which strikes me to be very similar to the concept of imagination. How is it we imagine things that we have never experienced?

    One analogy I like is that of a delicious cake. A cake is made of various ingredients, but there is no ingredient called "deliciousness". Deliciousness simply emerges as the the result of the physical manifestation of the ingredients.

    I will admit that I have not the foggiest idea of why when certain neurons fire in a certain way that I have feelings, emotions or even thoughts. That will probably remain one of the greatest mysteries of all time. But moving that explantion to some other realm does not solve the problem for me, it merely defers it.

    However, if I were a dualist the "no ectoplasm" clause would not prove anything. I could always object that the missing brain ectoplasm contained the link or channel that connected the brain to the non-material mind for a given mental function.

    Alan

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  2. By the way, whenever I see a documentary on brain function, I am reminded just how primitive our knowledge of the brain really is.

    On one level we have a good understand of how a single neuron works. We can explain bio-chemically how the neuron fires and transmits impulses across its synapses, etc.

    On another level we can point to a region of the brain and say that its responsible for X.

    But we seem to have idea how neural networks make X happen.

    Its like looking at a computer and thinking we understand how it works by pointing to the memory module and saying that its responsible for memory.

    That does not mean we understand how the various logic gates store a data byte.

    Nor does it mean we know how transistors come together to make a logical gate.

    Nor does it mean we know how semi-conductor elements make a transistors work.

    Nor does it mean we understand the physics behind electrons that make semi-conductors work.

    Oh, then there is the whole software thing. How can we point at that? Its like consciousness -- there is no part of the computer we can point at and say that's the software running.

    You see we can keep drilling down deeper. I would argue that in brain science we are still pointing at the memory module on one side. And maybe understanding how individual transistors work on the other side. Its that all important part in the middle that we are still clue-less about.

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  3. I've wondered if maybe this all applies to our opinions about religion, politics, social issues etc. as well as our emotions.

    Is it possible that we feel the way we do about certain subjects, that we accept certain ideas and reject others, or are either skeptical or credulous because our genes and experiance wire our brains that way?

    If that's the case, can the individual really be blamed for not changing his or her mind?

    I don't know, just throwing out topics for discussion.

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  4. Noah,

    I think you are probably correct to some extent. I'm sure there are differences in our brain wiring due to genetics and the interplay with early experience that makes some of us more naturally skeptical and endows others with more of a need to believe.

    In the interest of fun, lets take it a step further: If the the Universe is deterministic, i.e. every single event, electron and particle interaction has to happen by the rules of physics, then none of us have any choice except to be exactly what we are today.

    The fact that I am typing this very comment into this very blog on this very computer was in effect an unavoidable consequence of the big bang. Every particle since the beginning of time has had to follow its path prescribed by physics and therefore every event, thought or idea in history was pre-ordained.

    Wouldn't be ironic if the Calvinists were right (but for the wrong reasons) about predestination?

    Whether or not the Universe is deterministic plays into the debate over whether we really have free will or whether we are just autonomons. Is free will just an illusion? And if it is an illusion, does it really change anything? Do we just decide to lie in bed and give up (though that decision would have also been predetermined) or do we go on anyway (as if we had a choice)? Does not society have to do what it needs to do anyway? Think about it too much and it makes your brain hurt -- remember you may have been destined to think about it at this precise moment since the beginning of time. :)

    Alan

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  5. I like thinking about stuff like this.

    The best I've been able to come up with so far, is even if our thoughts and actions are "predetermined", the factors going into that are so vast and wide that it's AS IF we have free choice. I'm not sure I need much more than that to have a happy life. But it's still fun to ponder.

    Noah

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  6. So are we predetermined to "have" free will? ;)

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  7. Wouldn't that be equally applicable to a soul? After all, the Non-Physical and unobservable proberties of a soul would still be CAUSING your actions and thus predetermining them.

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