Tag Archives: supervenience

Curse You Peter Higgs

“Mass was so simple before you. Mass was just a property. Actually it was just a property of having another property: inertia. Inertia was so simple, though. It was just the property of resisting changes in motion.

Of course, we all know what ‘resisting’ means. And, we all know what motion is: d/t. If anyone must ask what distance and time are…well, there is little hope for someone so dim. At least, there is little hope for such a dimwit in physics. Hah! It looks like someone needs a metaphysician!”

The line of thought is a big hit with dualists. Actually, it is the best thing about mind/body dualism, and is why it’s good to have mind/body dualists around. Without them, physicalism grows too complacent.

The physicalist can be forgiven. It seems so obvious what we mean when we say that something is physical. But what does that mean? Is it simply anything that’s the proper business of physics? Is physics itself the proper business of physics?

The question of what makes something physical is actually difficult, even within physics. Take the Higgs field. It is not a ‘thing’; it is not even a ‘property’ of a ‘thing’. It is a property of space. It is a phenomenon which physics considers, but it is really weird, from the perspective of the old extended/unextended divide which Descartes proposed.

Yet we are prepared to accept the Higgs field as something physical, along with apples and atoms. That’s because we have been prepared to accept the physicality of the Higgs field by accepting  the physicality of things like d and t in the Newtonian scheme, as physical. Time and distance are not any less weird – they are strangely malleable, for instance – but they are more easily recognizable as our own phenomena. We experience time and distance, and we are comfortable with the idea that physics is a phenomenology of time and distance.

If we have drilled down to the notion of physics as phenomenology, and understand phenomena as our experience, then the remaining question is: What is our experience? I am not sure there is an all-encompassing answer to that question. Yet I think we can say a few things around the question which are instructive as to the notion of physicality.

At base, our experience is identity, and identity is interdependence. If I am watching an egg roll off the counter and hit the floor, I am the one watching that egg. The rolling egg, among other things, is making me, me. The memories of eggs, dependent upon the shape, color, texture and historical context of my current experience, shape my thoughts and expectations regarding the egg, just as the color, shape and texture of the egg depend upon the impression that the kitchen light delivers to my eyes after it bounces off the rolling egg. That is what the notion of supervenience is getting at: identity is fixed by spatial and temporal history.

And such a thing cannot be ‘transcendent’. It comes with the here and now; (physical) existence has a tense. ‘Tenseless’ existence is a product of reflection and not what we directly experience. Transcendence, in other words, occurs in the storybook, not in the story (else we would never read a story twice).

The trouble with this whole picture is that it looks like a truism. If physicality consists of an interdependent identity which avoids transcendence, then what is left? Ghosts are live possibilities; so are Higgs fields. Of course, that is the point of physicalism. When we look at our experience in total, physicality seems to exhaust all the explanatory possibilities, or at least the ones we could hope to know.

 

 

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Is a Virus Alive?

life, living matter and, as such, matter that shows certain attributes that include responsiveness, growth, metabolism, energy transformation, and reproduction. – Encyclopedia Brittanica

Close enough, and encompassing the generally accepted criteria: responsiveness, reproduction, metabolism and adaptation. My older son asked the question about viruses the other day. I have been looking forward to this question. It means that he is prepared to understand some things about life which are important. It is a tricky question if considered from the wrong viewpoint. A virus displays some of the characteristics which define a living organism. It can respond to stimuli, attaching to the proper cells and injecting its genetic material through the cell membrane when it makes contact. It can replicate. It can adapt to avoid a host immune response. But it does not have the capacity to metabolize. It cannot, in other words, run its own show. It is entirely dependent on its host organism in that respect. Nor is the virus alone on the gray borders of life. Certain families of bacteria lack some essential metabolic processes which would make them autonomous. They must live inside another cell, and depend on their host’s metabolism to survive. Yet, they too can reproduce, adapt, and respond to stimuli in their environment. Because they have a membrane which is active, biologists are prone to give obligate intracellular bacteria, like mycoplasma and Rickettsia, a break. Most biologists are less charitable when it comes to prions. Prions are mis-folded proteins which replicate by somehow inducing their own conformal change in normally folded proteins with which they come in contact. Prions can reproduce, but they cannot metabolize. They cannot adapt much (although they have managed to pass from cows to humans), but they can respond to their environment, albeit in a very limited way. Still, the difference between the prion and the obligate intracellular bacterium would seem to be one of magnitude rather than quality. Differences in their classification reflect a little bit of membrane chauvinism on the part of biologists. The same prejudice is evident in the gray zone at the other end of the complexity scale. By our criteria for life, is a male angler fish alive? The fish can survive for a short period of time independently, but it cannot carry on its own metabolic processes independently for the long-term. It must rely on a female angler fish. It must quickly sniff out a female and attach itself to her, permanently. The male fish spends most of its existence as a tissue of the female angler fish’s body; its brief, free swimming existence is a transitional aberration. Its ability to adapt is extremely limited. Its existence can be mapped on an algorithm only barely more complex than the one which describes a prion’s lifestyle. So what does differentiate the male angler fish from a mycoplasma bacterium, a virus, or even a prion? A few extra membranes make the only difference. Even our own status as living things is at risk if we apply our criteria strictly. We can certainly reproduce, just like the viruses, obligate intracellular bacteria, prions, and angler fish. But it is questionable whether or not we can independently metabolize. We actually rely on hereditary intracellular symbionts for our primary metabolic process. Without these symbionts, our mitochondria, we could live only minutes on the metabolic processes encoded by our own genetic material. So, we can hardly be blamed for fudging our criteria. We certainly want to call ourselves alive. Since it looks and acts alive, we want to call the male angler fish alive. For practical purposes, we also want to call Rickettsia and mycoplasma alive, as well as viruses from time to time. As for the prions, it is often more convenient to view them as sophisticated toxins rather than living things. And that’s the upshot of my son’s question. The issue of whether or not a virus is alive is only confusing if we consider “life” an actual, efficacious thing. But life is just a category. When we look out across the terrible landscape of things, we see phenomena which cluster about each other by dint of their shared heritage. Our account of our cluster is biology, and our criteria for life provide the outline for our biological stories. This is correct viewpoint on the question of life, and what is alive. But this is not the popular viewpoint. The popular viewpoint attempts to preserve life as a thing, as vital essence or emergent property. Unfortunately, the popular viewpoint is not feasible. It leads inexorably back to the original question rephrased, “where is the life in a thing to be found?” In the end, we find that the essence or the emergent property is explained by the operational mechanisms and properties of the thing in question, but it in turn, explains nothing about the thing; it just notes where that particular thing lies on the vast, terrible landscape of things. Despite its glaring inadequacy, the popular viewpoint remains popular because it seems to save us from losing an idea that we don’t feel comfortable losing. But we don’t need to worry, becoming a category doesn’t vitiate life. We have the things which the category marks clustered around us after all, even if it’s only according to our viewpoint. We can’t escape life anymore than we can climb out of our skins. So, the answer to the question? Sure, a virus is alive – as long as you can explain why.

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They Solved It! They Solved It!

Geriatricians have solved the hard problem of consciousness! From the July 1st issue of American Family Physician: “Some validated scales, such as Pain Assessment in Advanced Dementia…use objective measures to assess pain intensity and response to intervention.” The objective measures: abnormal breathing pattern, increased vocalizations, observed tension in the face and body, and capacity to be calmed by caregiver voice and touch. In short, agitation is synonymous with pain. And how do we know this? Because the researchers have observed that opiates attenuated agitation in their subjects with advanced dementia. That’s how the scale and its underlying assumptions were validated at once.
Many have questioned the utility of philosophy. Well, here it is. The PAINAD scale is valid, no doubt. This is something that can be determined by definition. If two different people observe the same demented patient, it is quite likely, predictably likely, that the observers will come up with the same score on the scale. But that begs the question. The real problem is not coherence. Coherence does not make truth. The real problem is the truth of the claim that agitation represents pain in a person with advanced dementia. Such information is not available to us, at least not in the defined, quantifiable way which we would prefer.
We can’t know anybody’s pain, really. That’s because it is everybody’s pain that gives us the concept of pain in the first place. The sensation I experience when I grab an electric fence, for instance supervenes on the action of the fence charger, the conductivity of my body and the ground, activation of peripheral nocioceptors, mediation by inter-neurons in my spinal cord, and finally my thalamus and cortex where it is contextualized as my very own experience of shock. My experience of the shock from the fence, indeed all my pain experience, is unique. In the case of a shock from the electric fence, my experience is trivially unique – to the extent that I can predict my friend’s response if I tell him why he shouldn’t touch the fence. But the pain-concept supervenes on all those unique experiences in the same way that my own experience supervenes on the collection of events surrounding my hand’s contact with the wire. A thing called pain doesn’t appear out of the process. If that were so, I should have ready access to it and the PAINAD scale would be unnecessary. I would just slap some electrodes on the patient’s skull and watch for the pain signature in his cortical electrical activity. But I can’t, nor will I in the future, though I might have such a tool. Cortical electrical patterns might be the narrow point in the pain experience, the place where the difference in my experience and the patient’s is most trivial. But I must still correlate the activity with some report from the individual or a set of individuals in a similar condition. Some kind of PAINAD-type analogy will always be the best that I can do.
So what does this application of philosophy to pain treatment tell me? What use is philosophy? First, it tells me that I should not expect to fix everyone’s, or anyone’s, pain by stimulating their opiate receptors. The experience becomes pain-type only when it is put in context. We can easily imagine pain experiences where the opiate receptors play a very different role. Take the poet’s description of the pain of a broken heart. Do we write off his report entirely as a quaint analogy as opposed to our serious ones? If so, how is his report effective in communicating a sense of the experience to us? What do we say when we find out that he used laudanum and found some partial relief? Addressing the mechanisms of pain can only go so far, because mechanisms only go so far in explaining the painfulness of an experience.
The application of philosophy to pain can save me from a different pragmatist’s mistake in treating pain as well. I’ll pick on my surgical colleagues for a moment. On multiple occasions, I’ve had a surgeon tell me, “Nobody ever died from pain.” Inevitably, this little bubble of wisdom surfaces in reference to a patient whose pain management has passed from the surgeon to myself. My knee-jerk response is to point out that nobody ever died from hip arthritis either, but surgeons are still quite happy to replace hip joints. Yet I understand the pragmatic meaning of the statement: people have died from opiate overdoses, so we can’t just capitulate to a person’s demands for ever-increasing doses of opiates to treat their pain. As noted above, the notion that simply stimulating opiate receptors necessarily fixes pain is misguided. But there is a subtext. Death is measurable. Respiratory suppression due to opiates does something, and therefore it is real in way in which pain is not. When you get right down to it, pain can be ignored. But it isn’t that easy. The human condition won’t be ignored anymore than it will be medicated. The hard problem remains hard. It isn’t hard because our subjectivity is some spooky ectoplasm or narcissistic property. It isn’t hard because our experiences will never move a dial or tip a scale. It is hard because things which explain and are explained have a reality to them as much as things which do something, yet we’re stuck working with the functional things, like the observed behaviors in the PAINAD scale. So we have a tightrope to walk. We can only ever come close to helping others with problems like pain, and only then if we act comprehensively. We can never completely succeed. But that doesn’t mean we must fail. We can just never get too sure of ourselves when we do something like suppress a demented patient’s agitation with an opiate – and think we can call it good.

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