“Feelings, nothing more than feelings”

Physicalism is the thesis that everything is physical, or as contemporary philosophers sometimes put it, that everything supervenes on the physical. The thesis is usually intended as a metaphysical thesis, parallel to the thesis attributed to the ancient Greek philosopher Thales, that everything is water, or the idealism of the 18th Century philosopher Berkeley, that everything is mental. The general idea is that the nature of the actual world (i.e. the universe and everything in it) conforms to a certain condition, the condition of being physical. Of course, physicalists don’t deny that the world might contain many items that at first glance don’t seem physical — items of a biological, or psychological, or moral, or social nature. But they insist nevertheless that at the end of the day such items are either physical or supervene on the physical.

Daniel Stoljar, “Physicialism” (Stanford Encyclopedia of Philosophy,
first published February 13, 2001, substantively revised March 9, 2015)

Robin Hanson, an economics professor and former physicist, takes the physicalist position in “All Is Simple Parts Interacting Simply“:

There is nothing that we know of that isn’t described well by physics, and everything that physicists know of is well described as many simple parts interacting simply. Parts are localized in space, have interactions localized in time, and interactions effects don’t move in space faster than the speed of light. Simple parts have internal states that can be specified with just a few bits (or qubits), and each part only interacts directly with a few other parts close in space and time. Since each interaction is only between a few bits on a few sides, it must also be simple. Furthermore, all known interactions are mutual in the sense that the state on all sides is influenced by states of the other sides….

Not only do we know that in general everything is made of simple parts interacting simply, for pretty much everything that happens here on Earth we know those parts and interactions in great precise detail. Yes there are still some areas of physics we don’t fully understand, but we also know that those uncertainties have almost nothing to say about ordinary events here on Earth….

Now it is true that when many simple parts are combined into complex arrangements, it can be very hard to calculate the detailed outcomes they produce. This isn’t because such outcomes aren’t implied by the math, but because it can be hard to calculate what math implies.

However,

what I’ve said so far is usually accepted as uncontroversial, at least when applied to the usual parts of our world, such as rivers, cars, mountains laptops, or ants. But as soon as one claims that all this applies to human minds, suddenly it gets more controversial. People often state things like this:

I am sure that I’m not just a collection of physical parts interacting, because I’m aware that I feel. I know that physical parts interacting just aren’t the kinds of things that can feel by themselves. So even though I have a physical body made of parts, and there are close correlations between my feelings and the states of my body parts, there must be something more than that to me (and others like me). So there’s a deep mystery: what is this extra stuff, where does it arise, how does it change, and so on. We humans care mainly about feelings, not physical parts interacting; we want to know what out there feels so we can know what to care about.

But consider a key question: Does this other feeling stuff interact with the familiar parts of our world strongly and reliably enough to usually be the actual cause of humans making statements of feeling like this?

If yes, this is a remarkably strong interaction, making it quite surprising that physicists have missed it so far. So surprising in fact as to be frankly unbelievable.

But if no, if this interaction isn’t strong enough to explain human claims of feeling, then we have a remarkable coincidence to explain. Somehow this extra feeling stuff exists, and humans also have a tendency to say that it exists, but these happen for entirely independent reasons. The fact that feeling stuff exists isn’t causing people to claim it exists, nor vice versa. Instead humans have some sort of weird psychological quirk that causes them to make such statements, and they would make such claims even if feeling stuff didn’t exist. But if we have a good alternate explanation for why people tend to make such statements, what need do we have of the hypothesis that feeling stuff actually exists? Such a coincidence seems too remarkable to be believed.

Thus it seems hard to square a belief in this extra feeling stuff with standard physics in either cases, where feeling stuff does or does not have strong interactions with ordinary stuff. The obvious conclusion: extra feeling stuff just doesn’t exist.

Of course the “feeling stuff” interacts strongly and reliably with the familiar parts of the world — unless you’re a Robin Hanson, who seems to have no “feeling stuff.” Has he never been insulted, cut off by a rude lane-changer, been in love, held a baby in his arms, and so on unto infinity?

Hanson continues:

If this type of [strong] interaction were remotely as simple as all the interactions we know, then it should be quite measurable with existing equipment. Any interaction not so measurable would have be vastly more complex and context dependent than any we’ve ever seen or considered. Thus I’d bet heavily and confidently that no one will measure such an interaction.

Which is just a stupid thing to say. Physicists haven’t measured the interactions — and probably never will — because they’re not the kinds of phenomena that physicists study. Psychologists, yes; physicists, no.

Not being satisfied with obtuseness and stupidity, Hanson concedes the existence of “feelings,” but jumps to a conclusion in order to dismiss them:

But if no, if this interaction isn’t strong enough to explain human claims of feeling, then we have a remarkable coincidence to explain. Somehow this extra feeling stuff exists, and humans also have a tendency to say that it exists, but these happen for entirely independent reasons. The fact that feeling stuff exists isn’t causing people to claim it exists, nor vice versa. Instead humans have some sort of weird psychological quirk that causes them to make such statements, and they would make such claims even if feeling stuff didn’t exist….

Thus it seems hard to square a belief in this extra feeling stuff with standard physics in either cases, where feeling stuff does or does not have strong interactions with ordinary stuff. The obvious conclusion: extra feeling stuff just doesn’t exist.

How does Hanson — the erstwhile physicist — know any of this? I submit that he doesn’t know. He’s just arguing circularly, as an already-committed physicalist.

First, Hanson assumes that feelings aren’t “real” because physicists haven’t measured their effects. But that failure has been for lack of trying.

Then Hanson assumes that the absence of evidence is evidence of absence. Specifically, because there’s no evidence (as he defines it) for the existence of “feelings,” their existence (if real) is merely coincidental with claims of their existence.

And then Hanson the Obtuse ignores strong interactions of “feeling stuff” with “ordinary stuff.” Which suggests that he has never experienced love, desire, or hate (for starters).

It would be reasonable for Hanson to suggest that feelings are real, in a physical sense, in that they represent chemical states of the central nervous system. He could then claim that feelings don’t exist apart from such states; that is, “feeling stuff” is nothing more than a physical phenomenon. Hanson makes that claim, but in a roundabout way:

If everything around us is explained by ordinary physics, then a detailed examination of the ordinary physics of familiar systems will eventually tells us everything there is to know about the causes and consequences of our feelings. It will say how many different feelings we are capable of, what outside factors influence them, and how our words and actions depend on them.

However, he gets there by assuming an answer to the question whether “feelings” are something real and apart from physical existence. He hasn’t proven anything, one way or the other.

Hanson’s blog is called Overcoming Bias. It’s an apt title: Hanson has a lot of bias to overcome.

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Why I Am Not an Extreme Libertarian
Blackmail, Anyone?
NEVER FORGIVE, NEVER FORGET, NEVER RELENT!
Utilitarianism vs. Liberty (II)