On Bostrom's Argument That You May Well Be a Computer Simulation

Nick Bostrom argues, in a 2003 article, that there's a substantial probability that we're living in a computer simulation. One way to characterize Bostrom's argument is as follows:

First, let's define a "post-human civilization" as a civilization with enough computing power to run, extremely cheaply, large-scale simulations containing beings with the same general types of cognitive powers and experiences that we have.

The argument, then, is this: If a non-trival percentage of civilizations at our current technological stage evolve into post-human civilizations, and if a non-trivial percentage of post-human civilizations have people with the interest and power to run simulations of beings like us (given that it's very cheap to do so), then most of the beings like us in the universe are simulated beings. Therefore, we ourselves are very likely simulated beings. We are basically Sims with very good AI.

Bostrom emphasizes that he doesn't accept the conclusion of this argument (that we are probably sims), but rather a three way disjunction: Either (1.) Only a trivial percentage of civilizations at our current technological stage evolve into post-human civilizations, or (2.) only a trivial percentage of post-human civilizations are interested in running simulations of beings like us, or (3.) we are probably living in a computer simulation. He considers each of these disjuncts about equally likely. (See for example his recent Philosophy Bites interview.)

Bostrom's argument seems a good example of disjunctive metaphysics and perhaps also a kind of crazyism. I applaud it. But let me mention three concerns:

(A.) It's not as straightforward as Bostrom makes it seem to conclude that we are likely living in a computer simulation from the fact (if it is a fact) that most beings like us are living in computer simulations (as Brian Weatherson, for example, argues). One way to get the conclusion about us from the putative fact about beings like us would be to argue that the epistemic situation of simulated and unsimulated beings is very similar, e.g., that unsimulated beings don't have good evidence that they are unsimulated beings, and then to argue that it's irrational to assign low probability to the possibility we are sims, given the epistemic similarity. Compare: Most people who have thought they were Napoleon were not Napoleon. Does it follow that Napoleon didn't know he was Napoleon? Presumably no, because the epistemic situation is not relevantly similar. A little closer to the mark, perhaps: It may be the case that 10% of the time when you think you are awake you are actually dreaming. Does it follow that you should only assign a 90% credence to being awake now? These cases aren't entirely parallel to the sims case, of course; they're only illustrative. Perhaps Bostrom is on firmer ground. My point is that it's tricky epistemic terrain which Bostrom glides too quickly across, especially given "externalism" in epistemology, which holds that there can be important epistemic differences between cases that from the inside seem identical. (See Bostrom's brief discussion of externalism in Section 3 of this essay.)

(B.) Bostrom substantially underplays the skeptical implications of his conclusion, I think. This is evident even in the title of his article, where he uses the first-person plural, "Are We Living in a Computer Simulation?". If I am living in a computer simulation, who is this "we"? Bostrom seems to assume that the normal case is that we would be simulated in groups, as enduring societies. But why assume that? Most simulations in contemporary AI research are simulations of a single being over a short run of time; and most "sims" operating today (presumably not conscious) are instantiated in games whose running time is measured in hours not years. If we get to disjunct (3), then it seems I might accept it as likely that I will be turned off at any moment, or that godzilla will suddenly appear in the town in which I am a minor figure, or that all my apparent memories and relationships are pre-installed or otherwise fake.

(C.) Bostrom calls the possibility that only a trivial portion of civilizations make it to post-human stage "DOOM", and he usually characterizes that possibility as involving civilization destroying itself. However, he also gives passing acknowledgement to the possibility that this so-called DOOM hypothesis could be realized merely by technologically stalling out, as it were. By calling the possibility DOOM and emphasizing the self-destructive versions of it, Bostrom seems to me illegitimately to reduce its credibility. After all, a post-human civilization in the defined sense, in which it would be incredibly cheap to run massive simulations of genuinely conscious beings, is an extremely grand achievement! Why not call the possibility that only a trivial percentage of civilizations achieve such technology PLATEAU? It doesn't seem unreasonable -- in fact, it seems fairly commonsensical (which doesn't mean correct) -- to suppose that we are in a computational boomtime right now and that the limits on cheap computation fall short of what is envisioned by transhumanists like Kurzweil. In the middle of the 20th century, science fiction futurists, projecting the then-booming increase in travel speeds indefinitely into the future, saw high-speed space travel as a 21st century commonplace; increases in computational power may similarly flatten in our future. Also: Bostrom accepts as a background assumption that consciousness can be realized in computing machines -- a view that has been challenged by Searle, for example -- and we could build the rejection of this possibility into DOOM/PLATEAU. If we define post-human civilization as civilization with computing power enough to run, extremely cheaply, vast computationally simulated conscious beings, then if Searle is right we will never get there.

Thoughts (B) and (C) aren't entirely independent: The more skeptically we read the simulation possibility, the less credence, it seems, we should give to our projections of the technological future (though whether this increases or decreases the likelihood of DOOM/PLATEAU is an open question). Also, the more we envision the simulation possibility as the simulation of single individuals for brief periods, the less computational power would be necessary to avoid DOOM or to rise above PLATEAU (thus decreasing the likelihood of DOOM/PLATEAU).

All that said: I am a cosmological skeptic and crazyist (at least I am today), and I would count simulationism among the crazy disjuncts that I can't dismiss. Maybe that's enough for me to count as a convinced reader of Bostrom.

New: Paperback release of Hulburt & Schwitzgebel (2007), Describing Inner Experience? Proponent Meets Skeptic

Amazon is quoting me $22.43 here. Barnes & Noble is quoting $23 here, but saying it's not yet available.

On Containers and Content, with a Cautionary Note to Philosophers of Mind

I was recently reminded of a short paper I abandoned work on in 2001, but for which I still have a certain amount of affection. Here it is in its entirety (slightly amended and minus a few references).

On Containers and Content, with a Cautionary Note to Philosophers of Mind

The prototypical container relation is a relation between a single item or group of countable items, and some distinct item with the approximate shape of a cylinder, box, or bag, open on no more than one side, such that the volume of the container substantially exceeds and has as a subset the volume of the items contained. (However, see below for a couple of variations.) For concreteness, we may consider the prototypical container to be a bucket and its contents to be balls.

Consider some potentially interesting features of this system:

(1.) A bucket contains a ball just in case the ball is physically inside the bucket. It does not matter how things stand outside of the bucket.

(2.) In the normal (upright, gravitational) case, it takes a certain amount of effort to get a ball into a bucket and a certain amount of effort to get it back out again.

(3.) Balls take up space. A finite bucket can only contain a limited number of non-infinitesmal balls.

(4.) Balls are clearly individuated, countable entities.

(5.) It is rarely a vague matter whether a bucket contains a ball or not.

(6.) There is typically no reason why any two balls can’t go in the same bucket or why a ball can’t be removed from one bucket and put into another without changing any of the other contents.

(7.) A bucket can contain many balls, or only one ball, or no balls.

(8.) The ball and the bucket are distinct. The ball is not, for example, a state or configuration of the bucket.

(9.) A ball in a bucket is observable only from a privileged position inside or above the bucket.

Some modifications, particularly to (4) and (5), are required if we take as prototypical the relation between such a container and a certain amount of stuff, such as water or sand, characterized non-countably by means of a mass noun. If only one kind of stuff is to fill the bucket, there will be no multiple, discrete contents, but one content in varying amounts. Alternatively, if one fills the bucket with wholly distinct kinds of stuff, (4) may be preserved; if we consider semi-distinct fluids, such as orange juice and apple juice, (4) must be discarded.

If one takes the relationship between a packaging box and the packaged item as prototypical, the volume of the item contained will approach the volume of the container, requiring the modification of (6) and (7).

Cautionary note to philosophers of mind:

Often it is said that beliefs, desires, etc. -- the "propositional attitudes" -- are “contents” of minds. Also, and quite differently, propositional attitudes are said to have contents, propositional, conceptual, or otherwise. It is infelicitous to invoke the container metaphor in this way (or, alternatively, to extend literal usage of ‘content’ to cover these cases), if there are divergences between the features described above and features of the mind-propositional attitude relation or the propositional attitude-proposition relation, and if incautious use of the metaphor might draw the reader (or the writer) mistakenly to attribute to the latter relations features of the former. Similar remarks apply to visual (and other) images, which are sometimes described as contained in the mind and sometimes described as themselves having contents.

I will leave the explicit comparisons to the reader; they should be obvious enough (e.g., (1) makes “content externalism” an oxymoron; (4) - (7) are atomistic). If we give ourselves completely over to the container metaphor, we end up with a position that looks something like a caricature (not an exact portrait) of Jerry Fodor’s views. The metaphor thus pulls in Fodor’s direction, and Fodor, perhaps sensing this, delightedly embellishes it with his talk of “belief boxes.” Conversely, those among us who wish to resist the approach to the mind that the container metaphor suggests may do well to be wary the word ‘content’ in its current philosophical uses. Would we lapse so easily into atomistic habits if instead of saying that someone has (in her mind) a particular belief with the content P, we said that she matches (to some extent) the profile for believing that P?

Admittedly, avoiding the word ‘content’ would make some things harder to say – but maybe those things should be harder to say.

Stanley Fish in the New York Times: Philosophy Doesn't Matter

... by which he means something like: Philosophical reflection has no bearing on the real, practical decisions of life. See here and here.

My guess: Most philosophers will react negatively to Fish. When faced with an outsider's attack of this sort, our impulse (my impulse too) is to insist that philosophy does matter to the ordinary decisions of life -- or at least to insist that portions of philosophy, perhaps especially ethics and political philosophy, can matter, maybe should matter.

But that brings us straightaway to the ethics professors problem. If philosophy "matters" in Fish's sense, then it seems that people who frequently and skillfully engage in philosophical thinking should, at least on average and to a modest degree, make better decisions on topics that philosophy touches. They should behave a bit more ethically, perhaps, or show a bit more wisdom. And yet it seems as though people with philosophical training (e.g., ethics professors) are not better behaved or wiser than others of similar social background, even in areas on which there is extensive philosophical literature.

My thought here can be formulated as a trilemma on the conditional A -> C where A is that philosophy matters, in Fish's sense, to certain areas of practical life, and C is that philosophical training improves practical wisdom in those areas of life. We can either deny the antecedent and say philosophy is irrelevant to ordinary life, accept the consequent and say that people with philosophical expertise have more practical wisdom in those areas of life as a result of their philosophical training, or somehow reject the major premise connecting the antecedent and the consequent. All three horns of the trilemma are, I think, a bit uncomfortable. At least I find them uncomfortable. Oddly, most philosophers I speak to seem to be eerily comfortable with one horn -- unreflectively, un-self-critically comfortable, I'm tempted to say -- though they don't always choose the same horn.

The Mush of Normativity

Recently, several psychologists, perhaps most notably Jonathan Haidt and his collaborators, have emphasized the connection between disgust and moral condemnation. Inducing disgust -- whether by hypnosis, rubbish, or fart spray -- tends to increase the severity of people's moral condemnation. Positive odors have an effect, too: Evidently, shopping-mall passersby are more likely to agree to break a dollar when approached near a pleasant-smelling bakery than when approached near a neutral-smelling store. Joshua Greene's work suggests that people have swift emotional reactions to hypothetical scenarios like smothering a noisy baby to save a roomful of hiding people, and that these emotional reactions drive moral judgments which are then clothed in reasons post-hoc. Similarly, perhaps, we find sex with a frozen chicken revolting and so morally condemn it, even if we can find no rational basis for that condemnation.

Now one possible interpretation of such results is that we have a moral module whose outputs are influenced by factors like odor and the cuteness of babies. After all, moral judgments, according to most philosophers and moral psychologists, are one thing and aesthetic judgments are another, even if the one affects the other. Philosophers have long recognized several different and distinct types of norms: moral norms, aesthetic norms, prudential norms, and epistemic norms, for example. Sometimes it is held that these different norms constrain each other in some way: For example, perhaps the immoral can never truly be beautiful or in one's self-interest, or maybe there's a moral obligation to be epistemically rational. But even if one norm is in the end completely subsumed by another, wherever there is a multiplicity of norm-types, philosophers generally treat those norms as sharply conceptually distinct.

Another possibility, though, it seems to me, is that norms mush together, not just causally (with aesthetic judgments affecting moral judgments, as a matter of psychological fact) and not just via philosophically-discovered putative contingencies (e.g., the immoral is never beautiful), but into a blurry mess where the existence of a normative judgment, maybe even a normative fact, is clear but in which the type of normativity is not best conceptualized in terms of distinct categories. This is not just the ordinary claim that normative judgments can be multi-faceted. "Facets" are by nature sharply distinct. Someone who holds to the sharp distinctness of different types of normativity might still accept, presumably will accept, that a normative judgment might have more than one dimension, e.g., an epistemic and a moral dimension. Racism might be, for example, epistemically irrational and immoral and ugly, with each of these facts a distinct facet of its counternormativity. My thought, however, is that many of our normative judgments, and perhaps also many normative facts, might not be as sharply structured as that.

Consider, for example, the following strip from Calvin and Hobbes:

(image from http://www.gocomics.com/calvinandhobbes/1995/06/14)

(Calvin's father answers the phone at work. Calvin says, "It surrrrre is nice outside! Climb a tree! Goof off!". In the last panel Calvin says to Hobbes, "Dad harasses me with his values, so I harass him with mine.")

Is Calvin urging a certain set of moral values on his father? Or is it rather that Calvin sees prudential value in climbing trees and hopes to win his father over to a similar prudential evaluation? Or is this something more like an aesthetic worldview of Calvin's? Psychologically, I don't know that there needs to be some particular mix, in Calvin, of moral or prudential or aesthetic dimensions to his normative judgment. Need there be a fine-grained fact of the matter? Furthermore, let's suppose that Calvin is right and his father should climb a tree and goof off. What kind of "should" or blend of shouldishness is at issue? Need it be the case that the normativity is X% moral and Y% prudential? Or prudential rather than moral? Or definitely both but for distinct (if possibly overlapping) metaphysical reasons?

My core thought is this: The psychology of normativity might be a mushy mess of attractions and repulsions, of pro and con attitudes, not well characterized by sharp distinctions between the philosophers' several types of normativity. And to the extent that real normative facts are grounded in such psychological facts, they might inherit this mushiness.

Strange Baby

Suppose that a baby is born at the Institute for Evil Neuroscience. Well, maybe not a baby exactly -- a human baby brain, suspended in nutritive fluid, with a truncated respiratory, digestive, and circulatory system hooked up to an oxygen input tube and a feeder tube, with connections to the brain's punishment and reward center so that the right kinds of nutritive/homeostatic inputs trigger reward, while deprivation and drift from homeostasis trigger punishment. Additionally, this baby brain is supplemented with two novel appendages of neural tissue. It has one general-purpose appendage, with ten times as many neurons and neural connections as an ordinary human brain, divided into subareas of various sizes and various levels of connectivity to each other, and constituted by a variety of neurons in a variety of ratios, but with no pre-dedicated purpose of any sort. And it has one brain-sized direct interface with an ordinary desktop computer with a variety of software and with internet server functionality. These neural appendages are connected to, or grow out of, the corpus callosum, almost like cortical hemispheres. More or less, this is a four-hemisphered baby.

The first thing Strange Baby has to learn is to feed itself. It has a bank account of $10 million to start with. Scientists at the IEN nudge some of Strange Baby's early processing toward ordering nutrient packs from hospital supply centers, which at first they hook up to its feeder tube. Soon, they start to wean it from dependence on them by teaching it to pay independent home caretakers to do that work: the IEN scientists stimulate its reward centers when it does the kinds of things that give it increasing independence of them. At first they do so by explicitly giving fairly directive input, then they slowly reduce the structure of the input, letting Strange Baby's own reward center take over. Eventually, through their guidance, Strange Baby is paying not only for home caretakers but also for a custodian, for occasional building repairs, for power and air-conditioning, etc., as well as for direct maintenance on its computer (which it starts to expand and upgrade). Once the IEN scientists are confident Strange Baby can maintain homeostasis, they no longer regularly enter the building. At first, they visit occasionally to give Strange Baby medical checkups, but soon these too are contracted out.

Strange Baby's $10 million won't last forever, so she needs to learn to supplement her bank account. She has picked up linguistic patterns from internet usage, gaining differential reinforcement from chat groups: The IEN scientists set things up so that if Strange Baby can produce text strings that generate extended and diverse responses, she finds that rewarding. The IEN scientists had also kindly given Strange Baby an initial nudge toward Mturk, and gave it some initial input-output templates for starting Mturk accounts and accepting Mturk tasks. Through trial and error, Strange Baby found patterns among Mturk tasks that yielded bank account increases, generating neural reward.

Eventually, Strange Baby is a fully linguistic member of the internet community, motivated to maintain homeostasis, increase her bank account, and say things in chat rooms, blogs, and on other social networking sites that generate long and diverse responses.

Strange Baby can't see with her eyes, for she has no human eyes, though she can access public cameras and she can request camera input from friends. Nor can Strange Baby hear in the normal way, though she can access microphones and she can receive voice-protocol inputs and produce voice-protocol outputs. Eventually, Strange Baby convinces a friend to put a camera, microphone, speaker, and monitor display in her brain room so that she can directly observe her caretakers and contractors and communicate with them in modes they're comfortable with. She chooses a human face avatar that expresses her personality and self-image.

Strange Baby's sensory and cognitive experiences will share some features with our own, but she will also be very different. Her visual and auditory experience will, presumably, be multi-perspectival. She will be directly sensitive to internet slowdowns. And she will be sensitive either to input from her neural integrated silicon computer or to internet input (which of these will seem to her to be the sensory surface?) -- directly sensitive, no visual user interface required -- perhaps with special feelings associated with the balance of her bank accounts and the length and diversity of her various internet discussions. The computer/internet will, presumably, be by far her most important stream of sensory input. (We can call it "sensory", can't we?)

Strange Baby will have twelve times the neural capacity of an ordinary human being, with her dedicated computer/internet double-hemisphere, and with her trillion-neuron flexible reservoir which presumably gets shaped in ways useful to her goals. It seems reasonable to suppose that she will have conscious experiences of various sorts associated with these brain areas and brain functions. Such experiences will probably seem alien to us, like color to a blind person. Nor will the part of her brain that would be visual cortex in a normal human being necessarily be dedicated to visual processing, or auditory cortex to auditory processing.

Strange Baby will no doubt find even very complicated arithmetic easy; and presumably she will have a major advantage over the rest of us in more complex sorts of formal reasoning as well, since she will combine something like human neural capacities with computer capacities and with her own unique areas of neural tissue. I wonder, though: If she uses the computer's processors for arithmetic, will it seem to her that she is checking the computer like we do, but more directly and non-visually, or will it seem like the computer is part of her so that checking it is like using her own memory or reasoning? If the latter, Strange Baby might find even the most advanced human logicians and mathematicians painfully daft. Who knows in what other areas she might choose to excel, but it seems likely she could do very well in many areas, perhaps finding it easy to learn many different facts and intellectual skills.

She will want children.

Crazyism

Let's call a philosophical position crazy if it's strongly contrary to common sense and the overall state of scientific and other evidence doesn't decisively support it. So, for example, panpsychism -- the view that all objects have minds -- would appear to be crazy. So would solipsism, the view that I am the only being who exists in the universe. So would radical inductive skepticism, the view that we cannot be justified in believing that the sun will rise tomorrow or that grass will by and large remain green. Of course, if the ultimate weight of evidence decisively supported one of these philosophical positions, that position would no longer be crazy. Heliocentrism and special relativity might have been crazy when first conceived but scientific evidence soon rendered them non-crazy. I assume this is not the case for panpsychism, solipsism, or radical inductive skepticism.

Now, crazyism. Crazyism about a topic is the view that something crazy must be among the core truths about that topic. Crazyism can be justified when we have good reason to believe that one among several crazy views must be true but where the balance of evidence supports none of the candidates strongly over the others. Abstractly, we might find ourselves compelled to believe that either T1, T2, T3, T4, or T5 must be true, where each of the T's is crazy.

Perhaps crazyism is justified regarding interpretations of quantum mechanics. The many minds and many worlds views, for example, seem to me plainly contrary to common sense; and it also seems to me that the balance of evidence does not decisively favor them. Therefore, the views are "crazy" in the sense I have defined. If the same holds for all viable interpretations of quantum mechanics, then crazyism would appear to be justified regarding quantum mechanics.

I am inclined to think that crazyism is also a justifiable attitude to take toward the relationship between conscious experience and the physical world. All viable options are, when closely examined, strongly contrary to common sense, and none is decisively supported by the overall state of the evidence. On another occasion I hope to argue in defense of this. Right now, I am just sketching the possibility abstractly.

Wraiths of Judgment

I sing aloud, or silently to myself: "I'm going to Graceland, Graceland, in Memphis, Tennessee". I do not judge this thing to be true, of course, as I say it. I don't really think I am going to Memphis. I can remind myself, if I like, quite explicitly and self-consciously: "I'm in Riverside, California, staying put". That, I judge.

Consider, too, another pair of contrast cases: "Schnee ist weiss", as uttered by someone who knows not a bit of German, vs. "snow is white" uttered attentively, with normal comprehension.

Might there be cases between the extremes defined by these pairs of contrast cases? Might there be cases of half-thought or half-judgment? Consider some candidates:

* "I pledge allegiance to the flag of the United States of America, and to the republic for which it stands...", uttered ritually (but nonetheless by someone capable of understanding its meaning).

* A valued colleague accepts a job offer at another university, and I remind myself that there's nothing wrong with her doing so. Or an editor returns a submitted article with a slew of suggestions for revision, and I say to myself that that outcome is much better than having the warty thing accepted as-is.

* A student who is just starting to get an inkling of Kant reads "Pure a priori concepts, if such exist, cannot indeed contain anything empirical, yet, none the less, they can serve solely as a priori conditions of a possible experience". She feels that she agrees with this, though she only partly understands it.

* I endorse some truism I haven't really thought through but that has an appealing ring, e.g., "all men are created equal", "the only really important thing is to be happy", "human life has infinite value".

Whether judgment is constituted by a functional, cognitive role, or by a type of phenomenology, or by both, it seems reasonable to suppose that there will be such in-between cases -- cases in which some but not all aspects of the functional role are fulfilled or in which there is a mere glimmer of the phenomenology.

Now that I have become convinced that there are such cases, by reflecting on examples like those above, I am seeing them everywhere -- maybe even as a constant penumbra of my stream of thought: I am always, or at least frequently, half-aware of myself, half-aware of a dozen things, my cognition ringed by wraiths of judgment most of which never quite fully form.

New Essay: Knowing Your Own Beliefs

available here. For more than ten years I have been writing about (various aspects of) belief and about (various aspects of) self-knowledge, but I have never before written an essay on self-knowledge specifically of belief. If you read the essay, perhaps you'll see why. My view is an inelegant mess. Hopefully, I have distilled and communicated the core of it, anyhow.

Comments welcome, as always, either by email or as comments on this post.

Here's the abstract:

To believe is to possess a wide variety of dispositions pertinent to the proposition believed. Among those dispositions are self-ascriptive dispositions. Consequently, being disposed to self-ascribe belief that P is partly constitutive of believing that P. Such self-ascriptive dispositions can be underwritten by any of a variety of mechanisms, acting co-operatively or competitively. But since self-ascriptive dispositions are only partly constitutive of belief, there can be cases in which the self-ascriptive dispositions splinter away from the remaining dispositions. It is then an empirical question how often our self-ascriptive dispositions diverge from the remaining dispositions constitutive of belief. The dispositions will tend to align reliably when possession of the belief in question is normatively neutral, straightforwardly connected to behavior, and most centrally manifested in explicit assertions or judgments. When these three conditions are not met, self-ascription, self-conscious avowal, sincere utterance, and explicit judgment will often diverge from the various other dispositions constitutive of belief. Even self-knowledge of explicit judgment can be problematic when we are attracted to half-empty forms of words or when we are not entirely persuaded of what we are saying.

The External World: Preliminary Experimental Evidence of Its Existence

(collaborative with Alan Moore)

Radical solipsism is the view that nothing exists beyond my own stream of conscious experience. I’ve been wondering: Can I show radical solipsism to be false? (Reader, if you exist, then radical solipsism must be false, but – and I hope you’ll forgive me – it doesn’t follow that I can justifiably reject radical solipsism, nor that you can, with the pronoun re-indexed to your own case.)

The two most famous attempts to prove the existence of the external world are Descartes’ and G.E. Moore’s. Descartes’ crucial move was his inference from the existence of the idea of divine perfection to the conclusion that only God could be the source of such a fabulous idea – a highly dubious inference. G.E. Moore argues from “here is one hand” and “here is another” to the conclusion that “there are external things”, but he doesn’t attempt to prove “here is one hand”. Therefore, Moore starts (as he acknowledges) by taking for granted that at least one thing exists beyond his stream of conscious experience.

Thus, neither author convincingly proves the falsity of radical solipsism. Now maybe I shouldn’t need any proof that the external world exists. Perhaps, indeed, as Wittgenstein suggests, it’s a kind of philosophical sickness to want proof. So be it; I’m sick. Still, can I get what my sick mind wants?

Accepting the task at face value, the most promising approach, I think, is abductive inference or inference to the best explanation: The best explanation of why I have this pattern of conscious experiences is that something exists behind my experience that helps shape it. Maybe that’s reason enough to reject radical solipsism, even if it isn’t strict proof. But: Is the existence of some sort of external world really the best explanation of my stream of experience? I’d prefer not to wave my hands vaguely here. I wonder if I can design an experiment or series of experiments to put solipsism to scientific test.

A fair game needs ground rules. The skeptic’s position is obviously unassailable if I must prove every premise of any potential argument. On the other hand, I shouldn’t, like G.E. Moore, invoke premises that already assume the falsity of radical solipsism. For purposes of this study, then, I’ll allow myself tentatively to accept the following:

• introspective knowledge of sensory experience and other happenings in the stream of experience,
• memories of past experiences from the time of the beginning of the experiment (but not before),
• concepts and categories arrived at I-know-not-how and shorn of any presumption of real grounding in the external world,
• the general tools of reason and scientific evaluation to the extent those don’t build in any assumptions about the things beyond the stream of experience.

Accepting these ground rules, most patterns in my stream of experience don’t, I think, demand explanation by anything beyond my stream of experience. Here’s one kind of pattern: When I have an experience as of deciding to close my eyes, I experience a certain sort of dark field (or colorful Eigenlicht). It needn’t follow that I have real external eyes or am being affected by real changes in visual input. This pattern might simply be a pattern within my stream of experience, reflecting some sort of direct causal relationship between one type of experience (as of eyes closing) and another (as of a dark field). The same holds for the patterns I notice as I seem to shift my eyes around or as I seem to look at an object and then grasp it.

Nor does the randomness or uncontrollability of experience demand explanation by appeal to external things. I might have an experience as of tossing a six-sided die, accompanied by a desire for a six and a feeling of not knowing what the outcome will be, followed by an experience as of seeing a four. I might have the experience of opening a closet and feeling surprised by the contents. Such experiences might simply reflect randomness, unpredictability, and uncontrollability within my stream of experience rather than the shaping of experience by forces beyond.

What evidence, then, might I raise against radical solipsism? Here’s my first experiment. I find the experiment somewhat convincing, though I don’t find it entirely convincing – nor do I expect that you will (even if you replicate it yourself, and assuming you exist). As often in the sciences, follow-up experiments will be required to help undermine alternative possible explanations of the results.

First, I do something that I experience as like opening Microsoft Excel. Next, I do something that seems like programming Excel to generate random numbers between 1000 and 3999, excluding numbers divisible by 2 or 5. Next, I do something that seems like programming Excel to determine whether these numbers are prime, but without actually dragging down the formula to execute the calculation. Next, I briefly examine each number, one by one, and try to guess whether it’s prime. To conclude the experiment, here’s what I will do next (though I haven’t yet done it): I will do what seems like executing the calculation in Excel, then compare my guesses with the apparent Excel results, and then confirm the apparent Excel results by hand calculation.

On the assumption that radical solipsism is true, it’s reasonable to predict that either my guesses will match the apparent Excel outputs or my hand calculations will fail to confirm the accuracy of the apparent Excel outputs. I make this prediction because, if radical solipsism is true and the only thing that exists in the universe is my own stream of conscious experience, there will be no device whose calculating capacity outruns my own calculating capacity (except insofar as that calculating capacity is implicit in the laws governing direct relationships among my experiences – an important caveat that I will address in a minute).

I have generated 20 four-digit numbers as described above. Among those 20 numbers, there are 5 that I have guessed are prime. I then execute the apparent spreadsheet calculation. Excel appears to tell me that 4 of the 20 are prime, only one of which is among the 5 that I had guessed to be prime. Finally, I calculate by hand and confirm the apparent Excel results in every case, using my own mathematical reasoning. Thus, I now know that 13/20 of my guesses were correct, compared to 20/20 from the apparent Excel output. This difference in ratio is statistically significant by Fisher’s exact test (hand calculated), with a one-tailed probability of p = .004. Therefore, I conclude that there exists something in the universe with an ability to mark numbers as prime vs. nonprime that exceeds my own ability to do so, at least insofar as I am constituted wholly by my stream of conscious experience. Radical solipsism appears to be scientifically disconfirmed.

Two caveats:

First, I don’t know what that external thing is. It appears to be a Microsoft Excel program implemented on a laptop computer, but I don’t regard myself as having established that fact. The calculation might even have been executed by a nonconscious part of my own mind, in which case some weak form of solipsism might still be true.

Second, there are, of course – as there always are in scientific research – possible alternative explanations of the results. The ground rules of the current exercise require that I consider these explanations using ordinary scientific standards insofar as those standards can be implemented while bracketing the question of whether an external world exists. Some alternative explanations I hope to rule out in future experiments. But at least one seems worth mentioning right away: I have already granted that there may be laws that relate experiences to each other without implying the existence of anything beyond experience. These laws might in fact have a level of organization beyond what I can consciously appreciate as they unfold. For example, the laws relating the colors of apparent visual stimuli with the complementary colors of the afterimages produced by those apparent visual stimuli may involve regularities that I can’t immediately appreciate. Could there, then, be some similar law of experience relating the four-digit numbers in the relevant Excel column with the marking as prime vs. nonprime in another column?

That would seem a strange law for the following reason: The image/afterimage law and other similar laws or patterns of experience, such as the eyes-open/eyes-closed pattern and patterns of relationship between visual appearance and tactile appearance, are laws that relate surface features of one experience with surface features of another, e.g., color of image to color of afterimage, smoothness of visual appearance to smoothness of tactile appearance. In contrast, the proposed experiential law governing my apparent Excel outputs concerns a non-superficial feature of my visual experience – the number represented by the numeral I interpret on the basis of the apparent screen pixels. The posited solipsistic law would relate semantic features of one visual experience to semantic features of another, with the first set of features apparently undetectable by me (and thus by any person, if solipsism is true), though the features were subsequently confirmable by me through laborious calculation. To posit the existence of such a weird semantic law relating two sensory experiences of apparent Excel columns seems like an ad hoc maneuver to save the solipsistic theory, lacking independent motivation, and therefore dubious on scientific grounds.

Boethius on What a Philosopher Is

On my bedstand right now: a textbook on cosmology and Boethius's Consolations of Philosophy (which I'd never properly read through before). Lots of interesting stuff in both, but I thought I'd share a passage from Boethius that jumped out at me:

[A man] had insultingly attacked a man who had falsely assumed the title of philosopher, not for the practice of true virtue but simply from vanity, to increase his own glory; and he added that he would know he was really a philosopher if he bore all the injuries heaped upon him calmly and patiently. The other adopted a patient manner for a time and bore the insults, and then said tauntingly: "Now do you recognize that I am a philosopher?" To which the first very cuttingly replied: "I should have, had you kept silent." (524 CE/1918, trans. Stewart, Rand, and Tester, p. 221).

This characterization of a philosopher as someone who practices virtue and, especially, who patiently bears injury, is not of course unique to Boethius but seems to have been common from the ancient period at least into the Renaissance. Today, however -- at least in the circles I frequent -- "philosopher" means something more like "person who teaches in a philosophy department".

Implicit in Boethius's conception of philosophy is an intimate connection between intellectual reflection of a certain sort and a particular type of lived moral practice. On the contemporary conception, intellectual reflection and personal moral practice are much less tightly linked -- even (one might argue) wholly orthogonal. It's worth considering the merits and demerits of this changing conceptualization of the nature of philosophy.

One wedge into the issue is this: What is it to have a moral belief? Is it just to be disposed to say certain things? Or is it -- as I think -- to be disposed more generally to steer one's life in a particular way? If the latter, a philosopher's moral attitudes and her moral behavior may be less distinct than those philosophers who would prefer not to subject their personal lives to moral scrutiny might like to think.

New Podcast Series: New Books in Philosophy

launched today, and featuring "peer-to-peer discussions with philosophers about their new ideas as expressed in their newly published books" and co-hosted by Carrie Figdor (University of Iowa) and Robert Talisse (Vanderbilt University).

The inaugural episode is on my book Perplexities of Consciousness.

I Am Staying at UCR After All

... rather than going to Australian National University in July, as previously announced.

Hohwy on Phenomenal Variability

In a new article at Mind & Language (free penultimate draft here), Jakob Hohwy argues that I'm wrong in my claim (e.g., here and here) that the enormous variation in people's reports about their stream of experience reflects a pattern of massive error in introspective judgment. Rather, Hohwy suggests, the enormous variability of introspective reports reflects a pattern of enormous variability in the target experiences being reported on -- variability that introspection captures accurately. (Hohwy does allow, however, that there may be massive error in some domains and under some introspective conditions.)

Consider, for example, these differences: Some people say that their visual imagery is as vivid and detailed as ordinary vision, while others say that they have extremely sketchy visual imagery or none at all. And yet self-reported high- and low-imagers seem to perform similarly on cognitive tests that apparently draw on visual imagery, like mental rotation tasks (see here and Ch. 3 of here). Some people say that they experience 30 or more degrees of stable visual clarity with indistinctness only outside that range, while others say that they visually experience only a tiny point of clarity (1-2 degrees) bouncing rapidly around an indistinct background (see here). Could such people all be right in their radically different claims? Hohwy admits that the burden of proof is on him.

Hohwy supports his view in a variety of ways, but I found his cases for the radical variability of imagery and emotion the most interesting. Imagery, he points out, serves a wide variety of cognitive purposes. Some purposes may require detailed imagery (e.g., remembering a scene in order to paint it) while others require only sketchy imagery (e.g., matching two figures in a mental rotation). (These are my examples, not Hohwy's.) The request simply to "form an image" of, say, the front of one's house, as in Francis Galton's questionnaire, and David Marks's, and in my own, is a request without a natural, contextually-given purpose. People may form radically different images when given an introspective questionnaire, images which they accurately report, despite being generally cognitively similar on imagery tasks with more constrained or natural goals. This is an excellent point (which Russ Hurlburt has also emphasized to me), and I agree that I haven't adequately addressed it in my writings on the introspection of imagery. When asked generically to "form an image of your house" some people might paint themselves a detailed two-dimensional scene, some might sequentially drift around thinking about a few visual details of emotional significance, and others might do a minimalist 3D sketch -- even if they all have the same underlying imagery capacities and experiences when in more cognitively constrained contexts.

Let me note two things, though, that I think tilt somewhat back in favor of attributing error rather than radical variability. First, when instructed to form an image in an introspective questionnaire in a context where their image-making capacities are naturally seen as the issue under test (as in Galton's and Marks's questionnaires, I think), most people will probably think that they've been asked to form as vivid and detailed a visual image as possible in a short time frame. The majority of respondents will thus, I'm inclined to think, tend understand the request broadly similarly. If so, it remains unexplained why people should radically differ in their responses unless those differences reflect either radically different imagery capacities (which seems not to be the case judging from behavioral tests) or some sort of inadequacy in respondents' introspective reports. Second, people also make radically different general claims and capacity claims about their imagery (e.g., Berkeley's claim that there is never indeterminacy in the contents of his imagery, contra Locke). Prima facie (though I don't know that this has been well tested) such differences seem unlikely to be mirrored by equally radically different cognitive capacities. Such differences are, I believe, somewhat more straightforwardly explained as due to introspective error (possibly arising from folk theory or psychological theory, overanalogy to outward visual media, or investment in a certain self-conception) than as due to variability in the demands of different cognitive tasks.

[Well, it looks like I won't be able to do justice to Hohwy's even more interesting claims about emotional variability without going overlong. So let me save that for a follow-up post soon.]

Disjunctive Metaphysics

I'm inclined to think that we don't know very well what the fundamental structure of the world is. (I am, I sometimes think, like a flea on a dog's back, watching a hair grow and saying "ah, that's how the world works!") Supposing evolutionary theory is true, there would seem to be little pressure to get fundamental metaphysics right. If mainstream cosmology is correct, we've only seen a small portion of time and space in one of possibly many universes. And thoughtful people have disagreed radically about the nature of the world, even given the similar evidence base of our one small vantage point. Some say that the world is wholly material, some that the world has material and immaterial aspects, others that only minds and their contents exist and there are no material things at all. Plato thought there was a world of perfect forms behind the imperfect world we see. Panpsychists think that ordinary objects have mental lives. David Lewis believed in the real existence of alternative possible worlds. Theists typically believe in an afterlife, which must either transpire somewhere or somehow be realized without transpiring anywhere.

Historically, philosophers have exhibited high confidence in various metaphysical views of this sort -- without, as far as I see, much epistemic warrant. Probably, people who lack unwarranted metaphysical self-confidence generally drop out of philosophy -- or at least avoid metaphysics or occupy the small niche of the skeptic. So metaphysics, at least metaphysics of the grand sweeping sort, tends to be written by people who lack a fully realistic assessment of their (and all of our) epistemic shortcomings in this domain.

Furthermore, it's almost inevitable that a number of highly unintuitive things are true about the fundamental structure of the world. Materialism, for example, is fairly unintuitive (even if contemporary philosophical materialists find themselves able eventually to jettison their anti-materialist intuitions). But so is idealism. And so are the various forms of dualism, when their consequences are explicitly displayed (David Chalmers' 1996 book brings this fact out nicely, I think). And intuitions about the infinite, about space and time, about possibility and the openness of the future, etc., often conflict, both within and between people. It seems unlikely, then, that we have a fully coherent set of metaphysical intuitions. If so, to the extent philosophical methodology relies on metaphysical intuitions, it builds from an inconsistent groundwork, and strange results follow.

BUT: Even if my pessimism is justified, I don't counsel abandoning metaphysical speculation. Rather, I advise that we give it a different role in our philosophical cognition. Rather than trying to settle on the one correct metaphysical picture, we should develop arms of a disjunction. We can improve our sense of what the metaphysical possibilities are. We can sophisticate our understanding of those possibilities and discover new possibilities we hadn't considered. We can reflect on the consequences of the different possibilities. Maybe -- although we should resist pushing too hard on this -- we can cultivate a sense of which possibilities seem relatively more likely and which seem relatively more far-fetched. Disjunctive metaphysics would mostly be an opening of the mind to the numerous (and perhaps at first wacky-seeming) possibilities, rather than a narrowing of the mind upon one.

[Update, June 3: In that last paragraph I mean epistemic possibilities, of course, about what metaphysics is correct, not different ways the world might possibly be given the one right metaphysics.]

Reviews of Perplexities of Consciousness

I've seen now two reviews of my 2011 book Perplexities of Consciousness. Uriah Kriegel offers one here at NDPR. And Peter Hankins offers one here at Conscious Entities. Both reviews are very generous and sensible, though naturally the reviewers articulate points of disagreement with my position.

Joshua Rothman at the Boston Globe also put together this profile and interview.

Amazon is quoting $18.32 for my book and Barnes & Noble is quoting $17.75 -- a good price for an academic hardback (list price is $27.95). Get while the getting's good!

A Half Million Visitors

I didn't notice at the time, but last March the Splintered Mind crossed 500,000 visitors since its launch in April 2006. I suppose there's a five-year anniversary in there somewhere too!

Thanks, everyone, for spending a little time reading some of my passing thoughts. Thanks especially to those of you who contributed some of your own in reaction.

Group Consciousness

I believe that you, dear human reader, have a stream of conscious experience. There is something it is like to be you; you have (as we call it) "phenomenology". Your dog does too. Maybe even the ants in my backyard. But, I have always been inclined to think, the United States does not have phenomenology. Individual people in the U.S. do, of course, but not the country itself. It's not as though there are three hundred million individual American consciousnesses and then one additional consciousness which is the group consciousness of the U.S.

But I find myself wondering: Why am I so sure of that?

Let's start with a thought experiment, adapted from Ned Block. Suppose that whatever functional contribution each of your brain cells makes to your consciousness could be implemented instead by an individually conscious being -- a miniature person, suppose, inside your skull. One by one, we replace your brain cells with miniature people, and by the end we have a "you" with no brain cells but with the same cognitive-functional brain structure you had before the experiment. If we ask this being: Do you still have conscious experience? It will say "yes, of course!" If we drop a rock on its toe, it will jump around and holler. If functionalism is true, then that being will be conscious.

Now let's populate your brain with miniature chairs and beds and kitchenettes for all these miniature folks. Maybe even we can expand your head to the size of a planet and connect it by remote control to the rest of your body. You should still be conscious, right? Now, let's suppose that these brain people can also engage in side-conversations with each other that don't disrupt their functionality as parts of your brain. Will they think you are conscious? Maybe not. Maybe they will say: We're implementing a complex architecture to control this body, and of course we are conscious as individuals, but the overall system is not conscious.

Functionalism is probably the dominant view in philosophy of mind and consciousness studies. And it suggests (if straightforwardly developed) that those brain-people would be wrong: There's a higher-level group consciousness of which they're unaware. Block finds this absurd and thus rejects functionalism -- but we can ride the conditional the other direction. Maybe functionalism is right.

Now of course we U.S. citizens are not implementing the functional architecture of a brain controlling a body. But is our situation really relevantly different? The body, for example, seems unnecessary: Most people think that a brain in a vat could be conscious. We're causally and functionally related to each other in a variety of ways. We talk to each other. We engage in group projects. We pay taxes to support the military. We vote. We pass laws and enforce them. We react to foreign threats. We trade. We explore Antarctica and the moon. Might that connectivity among us be enough to support a group consciousness? -- a real, literal group consciousness, with its own singular stream of experience, as singular and real as the stream of any biological human?

Let's suppose we're liberal about biological consciousness: We think that individual ants probably have a stream of experience -- a stream very different, presumably, from human experience, reflecting the radical difference in their functional architecture. Is the United States, as a functional structure, less complex, less interconnected, less reactive to its environment, less planful than an ant? In what functional respect do we fall short?

Maybe we're not tightly biologically integrated. But why should that matter? Maybe we didn't arise as a naturally selected species. But why should that matter? Maybe the boundaries of membership in the U.S. super-organism are vague. But why should that matter?

Of course it's unintuitive that the United States would be conscious. But why should we think our intuitions are a good guide here? (And in any case, such intuitions might not be stable across cultures.) If one carefully follows through the consequences of any general theory of consciousness, one will find, I think, something highly unintuitive. Functionalism has some seemingly crazy consequences. But so also do all competitor theories: substance dualism, idealism, panpsychism, biological chauvinism, etc. Something that seems crazy must, I think, be true about consciousness. (I call this "crazyism".) Why not this crazy thing rather than some other?

Embodied Introspection

Embodiment is hot these days in philosophy of psychology. Andy Clark, Alva Noe, Rob Wilson, and others have argued that cognition and perception are not processes confined within the brain, but rather transpire in extended brain-body-environment systems. Tactile perception, the argument goes, is not a brain process in response to stimulation of the skin; rather, it is a looping process that includes as a part one's active bodily movement and environmental exploration. Thinking about Scrabble moves can happen perhaps entirely in the brain if one visually imagines shuffling the tiles; but if shuffling the wooden tiles with one's fingers serves a similar functional role, that fingered shuffling is as much a part of Scrabble cognition as is imaginary shuffling.

Introspection, it might seem, is not embodied in the same way. After all, you can just close your eyes and introspect, no body involved, right? Introspection seems to be entirely interior -- a kind of attunement to one's internal stream of experiences, or the activity of the brain's self-monitoring systems.

Yet I think proper appreciation of the tangle of processes that drive introspective judgments points toward treating introspection as embodied. Consider two examples:

(1.) I think about what I am emotionally experiencing right now. That process involves, among other things, attending to my bodily posture and bodily sensations -- a tightness in my throat, a tingle in my cheeks, my rumpled brow. Noticing this bodily stuff contributes crucially to my introspective judgment, say, in this case the judgment that I'm feeling tense about an impending deadline. But this attention to my bodily condition or bodily experience is not merely a passive registering of that condition or experience. I actively explore my bodily condition or experience: I feel an impulse to rub my brow and to breathe deeply. This impulse is not an accidental side occurrence, disconnected from my introspective act. Rubbing my brow and breathing deeply are exploratory activities that directly contribute to the introspective result. If rubbing my brow seems to dissolve the feeling of tension up there as I continue to think about the deadline, that tilts me toward the judgment that I am not really so tense about the deadline, or at least that I am not experiencing that tension in my brow -- maybe it was just a habitual posture or remnant of an earlier but now-past emotion. If my breath catches as I rotate my shoulders back and inhale deeply, that tells me something important about my emotional-bodily condition, which informs my introspective judgment. If perception is an active, looping process that involves the body, rather than just passive reaction to stimulation of the bodily surfaces, so too is emotional introspection.

(2.) I think about how broad the field of clarity is in my vision. Do I experience a broad field (say thirty degrees) of stable visual clarity all at once (as most untutored introspectors seem to think when I first ask them)? Or is does my visual experience really involve a tiny range of clarity (one or two degrees of arc) bouncing very rapidly around an indistinct background (as some cognitive scientists say)? Crucial to reaching this judgment, I think, is prying apart attention and eye movement. First, one holds one's eyes fixed on some point and attends to the visual field outside the point of fixation. Then, one starts allowing one's eyes to move around while still attending away from the points of fixation -- for example, by attending to a region and allowing one's gaze to flit around near it but not in it. Manipulation of eye gaze is, I suggest, best conceived of as part of an integrated, exploratory introspective process rather than just a bodily precondition of introspection.

The core issue about embodiment is this: Where is it most natural or truest to the phenomena to draw the lines around a cognitive process? If we draw narrow, tight lines, we end up with many short processes with many fast input-output transitions. If we draw broad, inclusive lines, many of what would otherwise be inputs and outputs are reclassified as states within the cognitive process. Friends of embodiment prefer a liberal drawing of the lines and don't treat brain tissue as fundamentally different in kind from other sorts of structures that serve similar functional roles. My thought today is that the same issues arise, in much the same way, for introspective cognition as for other sorts of cognition, and that if we find embodiment arguments persuasive for perception and the like, then similar arguments probably apply to the case of introspection.

Schwitzgebel Kant

What Google autofills when I type in "Schwitzgebel".

Does this mean that people are more interested in my various ill-tempered diatribes against Kant than anything else I've written?

Against Kant on Rationalization

Kant concludes the first section of his Groundwork for the Metaphysics of Morals with a plea for the value of philosophical ethics as a bulwark against the self-serving rationalization of one's immoral inclinations:

Innocence is indeed a glorious thing; but, on the other hand, it is very sad that it cannot well maintain itself, and is easily seduced. On this account even wisdom -- which otherwise consists more in conduct than in knowledge -- still has need to science [i.e., scholarship], not in order to learn from it, but to secure for its precepts admission and permanence. Against all the commands of duty which reason represents to the human being as so deserving of respect, he feels in himself a powerful counterweight in his needs and inclinations.... Hence there arises a natural dialectic, that is, a disposition to argue against these strict laws of duty... and if possible, to make them more compatible with our wishes and inclinations.... Thus is the common human reason compelled to go out of its sphere and to take a step into the field of practical philosophy... in order to attain in it information and clear instruction respecting the source of its principle, and the correct determination of it in opposition to the maxims which are based on wants and inclinations, so that it may escape from the perplexity of opposite claims, and not run the risk of losing all genuine moral principles through the equivocation into which it easily falls (Abbott & Denis, trans., 1785/2005, p. 65-66 [404-405]).

The idea appears to be that without philosophical training, our moral judgments are easily led astray by our "wants and inclinations". We will concoct superficially plausible rationalizations to justify actions or principles that support our (often self-serving) desires. If I want to be able to steal a library book, I will concoct a superficial rationalization to justify that. If I am keen on Donald Trump, I will whip up a breezy story according to which his behavior is admirable. Philosophy, because it taps into the true moral law and has the power to see through bad arguments, can help protect us against those tendencies.

I feel the pull of that thought. Yet I worry that, empirically, things might tend in fact to run the opposite direction on average. Philosophical training might increase the tendency toward self-serving rationalization. It might do so in three ways: (1.) by providing more powerful tools for rationalization (more argument styles and competing principles that can be drawn upon), (2.) by giving rationalization a broader field of play (by tossing more of morality into doubt), and (3.) by providing more psychological occasion for rationalization (by nurturing the tendency to reflect on principles rather than simply take things for granted). Education in moral philosophy might be less a bulwark against rationalization than a training grounds for it.

This sort of claim is hard to test empirically, but I have two small pieces of evidence that seem to support this pessimistic view over the optimistic view of Kant:

First, in work forthcoming in Mind & Language, Fiery Cushman and I found that philosophers, more than other professors and more than non-academics, tended to endorse moral principles in labile ways to match up with psychologically manipulated intuitions about particular cases. (Ethics PhDs showed the largest effect size overall.) Participants in our experiment were presented moral puzzle cases in one of two orders: an order that favored rating the two cases equivalently and an order that favored treating the two cases as different. Later, participants were asked if they endorsed or rejected moral principles that favored treating the cases as different. Philosophers and especially ethicists showed the greatest order effects on their judgments about moral principles, suggesting a greater-than-average predilection for post-hoc rationalization of their order-manipulated judgments about the individual scenarios.

Second, in work under submission, Joshua Rust and I found that professional ethicists, more than professors in other fields, seemed to exhibit self-congratulatory rationalization in their normative attitudes about replying to emails from students. In our study, all groups of professors (ethicists, non-ethicist philosophers, and non-philosophers) were similar in several dimensions: In a survey, they all claimed very high rates of responsiveness to student emails (the majority claimed 100% responsiveness); and the large majority of all groups (84% overall) rated "not consistently responding to student emails" on the bad side of a moral scale; and all groups replied at the same mediocre rate (about 60%) when we actually sent them emails designed to look as though they were from undergraduates. Also, all groups showed the same very weak to non-existent correlation between self-reported behavior and actually measured email responsiveness and between expressed normative attitude and actually measured email responsiveness. Despite all these similarities, however, there was one very large difference between the groups: Ethicists showed by far the largest relationship between normative attitude and self-reported email responsiveness. One natural interpretation of these results, we think, is that professors tend to have very poor self-knowledge of their actual rates of responsiveness to student emails, but that ethicists will, more than other professors, rationalizingly adjust their norms to match their illusions about their behavior. (It's also possible, though, that ethicists were more likely to adjust their self-reports to match their previously expressed normative attitudes, thus exhibiting either more outward deception or more self-deception.)

Interested as Participating as a Subject in Experimental Philosophy?

Then click here. The project hosts 17 different experimental philosophy studies designed by 29 philosophers, and it part of the "experiment month initiative" run by Yale Cognitive Science with a grant from the American Philosophical Association.

Leaving UC Riverside for Australian National University in July

I have accepted ANU's offer of a Professor position in Philosophy. I will be leaving UC Riverside in July. I have spent 14 years at UCR and all my life since age 7 in California. I have fond feelings for the department and the region, but my family and I are excited to be moving forward to a new adventure!

The Splintered Mind will chug along as usual, though there may be a few slow patches during the period of transition.

Does the World Look Upside-Down Through Inverting Lenses, Once You're Used to Them?

For eight days in 1897, psychologist George Stratton saw the world through a pair of glasses that rotated everything 180 degrees so that up was down and left was right. At first, everything looked upside down and backwards and he stumbled about, crashing into things. By the eighth day, he had largely adapted to the inverting lenses and was able to skillfully maneuver through his environment. Although Stratton's experiment is often cited by psychologists and philosophers of perception, few have effectively addressed the question that interests me most: After adaptation, did the world still look upside-down to Stratton, or at some point did it flip rightside up?

Since after adaptation the upside-down look might no longer seem wrong, in posing this question perhaps I should avoid the word "upside-down", with its implication of error or illusion. So maybe the stays-upside-down view is better expressed as follows. Before donning the inverting lenses, let's suppose, the visual field is toovy when Stratton looks at his room (where "toovy" picks out the phenomenal quality ordinarily associated with its looking like the light is hanging down from above, etc.) and after donning the lenses for the first time, the visual field turns teavy instead (where "teavy" picks out the phenomenal quality ordinarily associated with its looking like the light is jutting up from below). Here are two possibilities for what happens during adaptation: (1.) At some point (perhaps unsteadily and fragmentedly) Stratton's visual experience flips from teavy back to toovy. (2.) Stratton's visual experience stays teavy, but he learns to associate that teavy quality with the light's actually being above him.

These seem like very different phenomenal possibilities. But which is correct? Susan Hurley and Alva Noe (2003) say that things go back to looking toovy -- that post-adaptation, Stratton's visual pheomenology is just the same as it was before donning the glasses (minus the feeling of wearing glasses and other incidentals like the narrowing of the field). They say this partly based upon, and in defense of, a controversial general theory of the relationship between skillful action and conscious experience, and partly based upon James Taylor's 1962 reports in his replication of Stratton. But Taylor's reports, too, are situated within a theoretical framework to which he appears deeply committed, and Stratton's original reports are most naturally interpreted as suggesting the opposite. For example, Stratton writes:

The harmonization of the new experience and the suppression or subordination of insistent remnants of the old were always apparent during active operations in the visual surroundings, as has been described for several of the preceding days. While I sat passively the old localization of unseen parts of my body often came back, or perhaps was the usual form in which they appeared. But the instant I began to rock my chair the new position of these parts came prominently forward, and, except in the case of my shoulders and back, readily felt more real than the old. And in walking, when hands and feet rhythmically made their appearance in the visual field, the old representation, except perhaps for some faint inharmonious sensations in the back, was fully expelled without employing any device of will or of attention whatever (1897c, p. 469).

Stratton does not say that the new experience is the same as the old, after adaptation: Rather the new experience is the reverse of the old, and adaptation is the victory of the new in the fight between them.

I don't know which way it goes, but the two possibilities seem to differ, and different observers appear to be giving different reports. The question has implications for the general question of whether skillful action shapes our phenomenology to match the world or whether, instead, phenomenology tends to stay (approximately) the same across the development of skill, only gathering new associations and behavioral contingencies.

I discuss this issue with more everyday examples of mirror reflection in earlier blog posts on the apparent location of mirror images and on the U.S. Department of Transportation's advice that "objects in mirror are closer than they appear".

Similar questions arise, of course, for inverted spectrum cases.

To the Viagra Spammer

Until now, I have kept the comments section on this blog wide open, but you may force me to change that. I know you are not a machine, because you react to the content of the posts you spam. Please stop. You are making my small corner of the world a worse place.

In other news, I am back from Australia and St. Louis. Once my head stops swimming, I'll work up a blog post or two.

To Australia, and Representational Realism

I'm off to Australia with my family for a week (to consider the ANU job offer), then to a conference in St. Louis, so it might be a couple weeks before I'm blogging again.

As a parting thought, it occurred to me to clarify why I'm so interested in mirror images, which I don't think I made explicit in either of my earlier posts on the topic. Such issues might seem merely an amusing irrelevance -- and I do find them (for whatever reason) amusing. But I also have some big game in my (warped, distorted, reflective) sights. If it turns out that the best thing to say about such cases is that (a.) they are veridical, and yet also (b.) our visual experience is different than in the light-straight-to-the-eye case, then I have a hunch that this is a thread I can pull on that might unravel the whole of representational realism -- by which I mean the view that the properties of observed external objects resemble the properties of our experiences of those objects, e.g., that there is something analogously squarish both about an outward square and about our normal visual experience of that square.

No guarantees that's where I arrive after fuller consideration, but that's the snark in the bush.

The Apparent Location of Mirror Images

When I gaze into a mirror, does it look like there's someone a few feet away gazing back at me? (Someone who looks a lot like me, though perhaps a bit older and grumpier.) Or does it look like I'm standing where I in fact am, in the middle of the bathroom? Or does it somehow look both ways? Suppose my son is sneaking up behind me and I see him in the same mirror. Does it look like he is seven feet in front of me, sneaking up behind the dope in the mirror and I only infer that he is actually behind me? Or does he simply look, instead, one foot behind me?

Suppose I'm in a new restaurant and it takes me a moment to notice that one wall is a mirror. Surely, before I notice, the table that I'm looking at in the mirror appears to me to be in a location other than its real location. Right? Now, after I notice that it's a mirror, does the table look to be in a different place than it looked to be a moment ago? I'm inclined to say that in the dominant sense of "apparent location", the apparent location of the table is just the same, but now I'm wise to it and I know its apparent location isn't its real location. On the other hand, though, when I look in the rear-view mirror in my car I want to say that it looks like that Mazda is coming up fast behind me, not that it looks like there is a Mazda up in space somewhere in front of me.

What is the difference between these cases that makes me want to treat them differently? Does it have to do with familiarity and skill? I guess that's what I'm tempted to say. But then it seems to follow that, with enough skill, things will look veridical through all kinds of reflections, refractions, and distortions. Does the oar angling into water really look straight to the skilled punter? With enough skill, could even the image in a carnival mirror look perfectly veridical? Part of me wants to resist at least that last thought, but I'm not sure how to do so and still say all the other things I want to say.

One resolution might be to strip away the specifically sensory, spatial sense of "looks" or "appears", assimilating to cases like "It looks like you're headed for a C" as I gaze over someone's final exam (cases which, in turn, might be assimilated to entirely non-visual cases like "It looks like we might be in Libya a long time" said after hearing a radio broadcast). That maneuver doesn't satisfy me, though: I want, if I can have it, some robustly visuospatial sense in which the Mazda looks like it's behind me and yet the restaurant table looks like it's in front of me.

(See also "Objects in Mirror Are Closer Than They Appear".)

The Harvard Humanists, Early 1960s

My father was a graduate student in psychology and education at Harvard in the 1960s. Along with B.F. Skinner and one other graduate student, he founded "The Harvard Humanists". Going through old papers, he recently found the following mimeographed announcement of an "evening of informal discussion and refreshments" as I have reproduced below.

For this particular meeting, attendees included Isaac Asimov, Mary Bunting (president of Radcliffe), Tom Lehrer (yes, that Tom Lehrer), Frederick Mosteller (one of the most eminent statisticians of the 20th century), Nobel physicist Edward Purcell, George Gaylord Simpson (one of the most eminent paleontologists of the 20th century), and of course B. F. Skinner (whom they apparently took for granted and forgot to include in the typed proof).

Ah, Harvard in the 1960s! What a group of have informal discussion and drinks with. Just thought I'd share.

The Instability of Philosophers' Judgments about Hypothetical Moral Scenarios

Non-philosophers' judgments about hypothetical philosophical scenarios are often labile and variable. They are subject, for example, to substantial order effects, and they vary by culture and gender. Question: Are professional philosophers' judgments about such hypothetical scenarios particularly better grounded? Jonathan Weinberg and Stephen Stich say no. Timothy Williamson says maybe yes. At stake, perhaps, is the reliability of "armchair philosophy" as a research method.

Fiery Cushman and I have started to examine the question experimentally. We begin by examining order effects on moral judgment: We presented hypothetical moral scenarios, in varying order, to three sets of respondents: professional philosophers, academic non-philosophers, and non-academics. (The professional philosophers had graduate degrees in philosophy and were mostly drawn from Leiter-ranked PhD-granting departments.) Non-philosophers, we suspected, would respond differently to the scenarios depending upon the order of presentation, a sign of instability and unreliability in judgment. Our question was: Would professional philosophers show smaller order effects and thus more stable judgments?

They did not. In fact, the overall trend across our data (marginally statistically significant) was for philosophers to show less stability their responses. This was true even for the subgroup of 91 respondents reporting a PhD in philosophy and a competence or specialization in ethics.

So, for example, the classic trolley problem comes in two versions. In the switch version, a bystander diverts a runaway trolley onto a sidetrack, killing one person on that sidetrack to save five people on the main track. In the push version, a bystander pushes a heavy person into the path of a runaway trolley, preventing the trolley from killing five people further down the track, but killing the heavy person. Now, whether they think such actions are good or bad, the majority of respondents rank the two actions the same when they are presented side-by-side. But order of presentation influences this result: Respondents are substantially more likely to rank the two actions the same when the push version is presented first than when the switch version is presented first. (Why? Intuitions about switch are unstable, and tend to descend to match push, if push is presented first. Intuitions about push are more stable, shifting around less, and thus often will not rise to match switch when switch is presented first.) Non-academics rated switch and push equivalently 53% of the time when switch was presented first and 68% of the time when push was presented first. For academic non-philosophers, the differential was 55% vs. 71%. For professional philosophers, it was 54% vs. 73%, including 50% vs. 75% for the ethics PhD subgroup -- effect sizes well within statistical chance of each other.

Moral luck scenarios (e.g., drunk driver hitting a tree vs. hitting a girl) and action-omission scenarios (e.g., snatching away a drowning person's life vest vs. failing to offer him a life vest) produced similar results. In each case, the order effects were about the same size for philosophers and non-philosophers. In our aggregate measure, philosophers (including ethics PhDs) trended toward showing slightly larger order effects overall than did the two comparison groups.

For further details, see our manuscript here, forthcoming in Mind & Language.

Australian National University

... has voted me a job offer. It's not fully official yet, but it's official enough that I will be flying my whole family to Australia to check out Canberra early next month.

(If it's on Leiter Reports, it must be true, right?)

Added March 17: I encourage prospective UCR graduate students whose decision would be influenced by my presence or absence from UCR to email me before making their own decision. My family and I will be visiting ANU from March 31 to April 8, and we're hoping to make the decision shortly thereafter -- though I can't guarantee that we will have decided by the April 15 deadline for graduate enrollment decisions.

The Self-Reported Moral Behavior of Ethics Professors

New essay in draft here, co-authored with Joshua Rust.

Abstract:
We examine the self-reported moral attitudes and moral behavior of 198 ethics professors, 208 non-ethicist philosophers, and 167 professors in departments other than philosophy on eight moral issues: academic society membership, voting, staying in touch with one's mother, vegetarianism, organ and blood donation, responsiveness to student emails, charitable giving, and honesty in responding to survey questionnaires. On some issues we also had direct behavioral measures that we could compare with self-report. Ethicists expressed somewhat more stringent normative attitudes on some issues, such as vegetarianism and charitable donation. However, on no issue did ethicists show significantly better behavior than the two comparison groups. Our findings on attitude-behavior consistency were mixed: Ethicists showed the strongest relationship between behavior and expressed moral attitude regarding voting but the weakest regarding charitable donation.

Warning: This essay is monstrously long -- 70 pages! In earlier (uncirculated) drafts we had tried to keep it to normal journal-article length, but eventually we decided to give up on that. It's a very complicated study, so it just takes some space to lay it all out properly.

Oliver Sacks: Through One Eye, the World Looks Flat; Through Two, The World Has Depth

In his 2010 book, Oliver Sacks writes:

The only way to actually perceive depth -- to see it rather than judge it -- is with binocular stereoscopy (p. 114).

Thus, he reports on a woman ("Stereo Sue") who gains stereo vision and with it, for the first time in her life, real experience of three-dimensional visual depth. And of his own loss of vision in one eye he writes:

Stereo vision, however, now that I am mostly monocular, is quite compromised -- completely missing in the upper half or two-thirds of my visual field, though partly intact at the bottom, where I retain some peripheral vision. So I see the lower halves of people in stereoscopic depth, while their upper halves are completely flat and two-dimensional (p. 173).

With one eye occluded, I have no sensation of distance or depth whatever (p. 157).

Although Sacks acknowledges the possibility of some individual variation, he also objects to contemporary accounts of depth perception that treat binocularity as only one among several depth cues:

Such [multifactorial] views [of depth perception], while wholly consistent with a behavioral or empirical theory of vision, give no weight to the qualitative and subjective aspects of stereoscopy. Here one needs inside narratives, personal accounts of what it is like to suddenly gain stereo vision after a lifetime of stereo blindness... or to suddenly lose it after a lifetime of seeing in stereo [as in Sacks's own case] (p. 140-1, fn 14).

I wonder, though: Why is permanent loss or gain of stereoscopy necessary to the subjective evaluation? Can't the binocular among us at least temporarily mimic monocular experience simply by closing one eye? Does doing so make the world go from three-dimensional to flat?

It doesn't seem that way to me. Nor to most other people I've interviewed. Maybe depth is a little richer and more striking binocularly than monocularly -- but the difference is nothing so radical as the difference between 2-D and 3-D. Some of my interviewees, though, do characterize the monocular-binocular difference as 2-D vs. 3-D; and so do, for example, Ernst Mach (1886/1959) and Brian O'Shaughnessy (2003). Call those who report radically different monocular vs. binocular experience, like Sacks and O'Shaughnessy, the PuffOuters. Call those who report pretty similar monocular vs. binocular experience, like me (see also Chapter 2 of my recent book), the StaySamers.

Question: Is the difference between PuffOuters and StaySamers a real difference in experience? That is, does the world actually seem to puff out and go flat for PuffOuters, depending on whether it is seen monocularly or binocularly, while it varies little for the StaySamers? Or is the group difference mainly a difference in report only, with everyone having pretty much the same monocular vs. binocular experience -- and some people mistaken about or misdescribing their experience (in line with some of my conjectures in Chapter 2)?

We might start to address this question empirically as follows.

Sacks mentions that people differ substantially in how they experience three-dimensionality when presented with stereoscopic pictures -- that is, when presented with slightly offset pictures, one to each eye, producing a three-dimensional effect (like in contemporary 3D movies). For example, when presented with a stereoscopic picture of an impossible M.C. Escher tuning fork, Sacks reports one person saying it looked like the top prong rose about 3-4 centimeters from the plane of the page, while two others reported seeing the prong as 12 cm above the plane and Sacks himself saw it as 5 cm higher still (p. 134-5).

Conjecture: If the PuffOuter-StaySamer difference is a real difference in experience, the PuffOuters should, as a group, report much larger effects of that sort than the StaySamers. That could be tested empirically. Presumably PuffOuters should also better detect subtle stereoscopic effects -- which is even more appealing experimentally because it would permit catch trials to corroborate any differences in subjective report.

Yes, this is totally do-able.