Appearances and Aboutness

March 22, 2011

The stimulus for today’s post is an article by Raymond Tallis that appeared in The New Atlantis for last Fall. This article takes a stand on many issues of interest to me and that I’ve written about in Your Brain and You. I find myself in fundamental agreement with some of what Tallis says, and also in fundamental disagreement with other points he makes.

Tallis makes far too many points to take up in one post. I’ll confine myself to two. The first is a point of agreement: There is no account that our sciences give of why there should be any appearances of things whatsoever. “Appearances” include the painful way damage to your body feels to you, the way a cup of hot coffee or a glass of iced tea feels to you, the way things look to you (bright or dim, this or that color), the way things taste and smell to you, and so on.

This point may be most easily seen with tastes and smells. Chemistry tells us that there are molecules of various kinds in the foods we eat and in the air near many flowers. Neuroscience tells us that molecules of each kind cause activation in some of our specialized sensory receptor cells, and not in others. Each of these cells stimulates some, but not all, of our neurons that lie deeper in our brains.

The specialized cells and their connections explain how we can react differently to different molecules arriving on our tongues or in our nostrils. But nowhere in the sciences is there an explanation of why or how the firing of our neurons causes orange flavor, chocolate flavor, lilac scent or outhouse odor.

Many contemporary philosophers are content to say that experiencing a flavor or a scent just is the very same thing as having a set of neural firings of a particular kind. This claim, however, does nothing to explain how it is possible for an experienced flavor or scent to be the same thing as a bunch of activities in nerve cells. The best that can be said for such an identity view is that it is simple, and that it cannot be proven to imply a contradiction. That’s a pretty weak reason: Berkeley’s view that there are just experiences and no corresponding material things is also simple and cannot be proven to imply a contradiction.

(Some self-professed identity theorists cheat. They make their view sound less implausible by writing of two “aspects” of neural events, or saying that neural events “lie behind” experiences, or that in experiences we “take a perspective” on neural events that is different from, and unavailable to, scientists who might be detecting the so-called same events with their instruments. But these palliative phrases all introduce some form of distinction between experiences and neural events, and they are not compatible with identity claims.)

My agreement that natural science does not explain appearances does not extend to Tallis’ favored way of arguing for this conclusion. That argument depends on “intentionality”, and the first thing to do is explain this word.

“Intentionality”, when a philosopher says it, means “Aboutness”. As in, your thought is about something. Of course, if you intend to do something – say, you intend to vote for candidate X – your intention is about something – in this case, it’s about voting for candidate X. But if you believe that Aunt Tillie is arriving tomorrow, your belief is about Aunt Tillie’s arrival. So, even though it’s just a belief and not an intention to do something, it has intentionality (as philosophers use this term) – that is, in plain English, it’s about something.

Some philosophers, including me, avoid “intentionality” whenever they can, and talk about aboutness instead, except when they discuss others who do use it. Many states besides intentions to act and beliefs can be about things or situations: these include hopes, desires, fears, doubts, supposings, wonderings, etc. One thing that makes aboutness interesting is that you can think about things or situations that do not exist. There are no unicorns and there are no men on the Moon at this writing, but that doesn’t stop anyone from thinking about those possibilities.

What about perceptions – are they about what is seen, heard, and so on? Tallis answers Yes, and this answer is a basic premise of the way he argues about appearances. My own answer is No.

This difference is fundamental, and it is a hot topic of discussion in the philosophy journals. A majority of philosophers are probably closer to Tallis’ view than to mine. There can be no hope of settling this issue in one blog post.

But it is relatively easy to provide a reason that raises some suspicion that seeing is very different from thinking. It’s a reason for separating appearance in visual experience from the processing of information about what is seen. And it is a reason that you can provide for yourself in your own home – as follows.

Sit by a window and look out at the buildings or trees or whatever is in the scene before you. (But if it’s a brick wall on the other side of a narrow alley, try a different window. You’ll need a scene where you can see something at significantly different distances.) Now, cover up one eye for about 20 seconds.

While you’re waiting, think about the character of your visual experience. I predict that you’ll agree that the world does *not* suddenly look flat. Nearby houses, for example, will still strike you as being seen as near, more distant houses as farther away. That may strike you as odd, because you may have learned that depth perception depends on cues from both eyes; and people who lose an eye do have some difficulty with such things as reaching for a glass of water. But there are many cues relating to distance. For example, you may know that houses in your neighborhood are roughly the same size. A distant house, however, takes up less of your visual field than a nearer one, and that helps you see it as more distant.

OK, now uncover your blocked eye. If you’re like me, you will experience a palpable restoration of a sense of depth. This too is somewhat puzzling: depth doesn’t dramatically disappear when you cover, but the restoration when you uncover is striking. I don’t know how to explain that, but it’s evident for me. (If anyone tries this and does not find what I find, I would be very interested to hear about it.)

What does this experience tell us? A point to note is that you will not have changed any judgments about what you’re looking at. Your thoughts about what is there will be the same. It is only a sense of depth – something like the difference between the 2D and 3D versions of movies – that is different. This difference is quite unlike a difference of opinion; it’s not a difference in what you think. It’s a difference in your visual experience.

It is almost routine in the philosophical literature to move from (a) the presence of depth in visual experience to (b) claiming that visual experience is about what is seen. But depth and aboutness are two different things. Visual appearances are one thing, judgments about what is seen are another. The judgments are often automatic, of course. You do not have to give yourself a conscious argument to get from appearances to things. You just effortlessly take it that you’re looking at a house, a car, an apple, or whatever. But the little experiment should help you see that the visual experience itself is a different thing from the judgment about what’s being seen.

[The article I’m responding to is by Raymond Tallis, “What Neuroscience Cannot Tell Us About Ourselves”, The New Atlantis, Number 29, Fall 2010, pp. 3-25. Thanks to Maureen Ogle for calling my attention to this article.]


Unconsious Processing and Political Smears

January 24, 2011

In a 2010 paper, Spee Kosloff and colleagues report several studies involving political smears that they conducted during the month before the 2008 election. The smears were that Obama is a closet Muslim extremist and that McCain is senile.

One of the studies measured an effect that worked entirely below the level of consciousness. Participants were presented with strings of letters that were either words or nonwords (of English) and they pressed one of two buttons to indicate whether the string was or was not a word. Before they saw the letter string, two other things happened. (1) They saw the word “trial” (in the same place where the letter string would appear) for about three quarters of a second – amply long enough to see it and read it. (2) Between the “trial” and the letter string, there was a very brief exposure (28.5 thousandths, or about 1/35, of a second) of either “Obama” or “McCain”, also where the word “trial” had been and where the letter string would immediately appear. This exposure is too brief to read; most participants were unaware that there had been a word flashed between “trial” and the string to be classified as a word or nonword. (The roughly 15%  who detected that there had been a word reported having had no idea what it was.)

Among the letter strings that were words, most had no relevance to political smears (e.g., “rectangle”, “lamp”), but a few were laden with such relevance. They were either Muslim-related terms, e.g., “Koran”, “mosque”, or senility-related terms, e.g.,  “dementia”, “Alzheimers”.

The measure in this study was the time it took from the onset of one of the laden words to the participant’s decision that it was a word. (Only correct decisions about word status were included in the data to be analyzed.)

The key results of this experiment are these. (a) Obama supporters decided that senility-related terms were words faster after “McCain” had been briefly flashed than after “Obama” had been briefly flashed. (b) Obama supporters were also faster than McCain supporters to decide that senility-related terms were words after “McCain” had been flashed. (c) and (d) are parallel results for McCain supporters and decisions about Muslim-related terms after the brief presentations of “Obama”.

In short, a presentation of a word too briefly to be consciously read can cause a measurable difference in the time it takes to decide that a politically laden word is a word. And this difference depends on the relation between the flashed word and one’s political views.

It may be tempting to downplay the significance of this result. It’s a special case, one might say.  The task is artificial. The differences in reaction time are smaller than time differences that are relevant to real world action.

But I think that such a dismissive reaction would be unfortunate. The special case and the artificial experimental set up are necessary to get a clear observational result. But the conclusion that the evidence thus gained supports is that an unconscious stimulus can engage a cognitive process (i.e., one’s views about a candidate) and can do so entirely outside of consciousness. The lesson I am inclined to draw from this study is that we have some direct evidence that unconscious processes can have cognitive richness.

A second experiment tested the effect of making race salient (and consciously so) on a group of participants who indicated that they were undecided as to which candidate they supported.

The experimental task was, again, to decide whether a letter string was a word or a nonword. Among those strings that were words, most were neutral fillers, but a few were Muslim-related terms. The measure was the time from onset of the letter string to the pressing of the button indicating the word or nonword decision. The only decisions of interest are those that correctly classified Muslim-related words as words.

The key manipulation was that immediately before the decisions on letter strings began, participants filled out a questionnaire about themselves, which either did or did not include a question about race. This question provided six racial categories and asked participants to circle those “that are personally relevant to your identity”. No participants circled “African American”. Those who got the question are the “race salient” group, with the remainder being the non race salient group.

Participants saw a readable word, “trial”, followed by a too-brief-to-read, 1/35 of a second exposure of “McCain” or “Obama”, followed by the letter string to be classified as a word or nonword.

The most interesting, and somewhat disturbing, results of this experiment are these. (a) Undecided participants who were briefly exposed to “Obama” and who had answered the race question were faster to correctly classify Muslim-related words as words than similarly exposed undecided participants whose form did not include the race question. (b) This difference was not present when the briefly exposed word was “McCain”.

Since the smear that Obama is a closet Muslim extremist was often repeated prior to the 2008 election, it is presumed that all participants were aware of it. It appears from this study that this background awareness did not become activated if the matter of race had not been very recently made salient. But if it was made salient, then it was sufficiently activated to quicken the response on the word status decision task.

The race question itself was, evidently, consciously processed by those whose questionnaire included it. But the decision task was done rapidly and there is no question of the participants having consciously deliberated about the relation between race and the word status decision. So, even though the salience of race worked through a conscious input, the process by which it reduced decision time worked outside of conscious deliberation.

Once again, it might seem that the results of these two experiments show something about unconscious processing, but are unimportant for larger life because the differences in reaction times are far smaller than the time it takes us to think of and decide to execute any conscious, deliberate action (including, as always, speaking or indicating intent with a gesture). For example, the fact that a decision about a word took a fraction of a second less would not show that the decision was any different from what it would have been without the brief exposures or the inclusion of the race question. A third study, however, casts doubt on such a hopeful view.

In the third study, participants read articles of about 600 words, one that elaborated on the Obama smear and one that elaborated on the McCain smear. The articles were written by the experimenters and designed to be parallel in the types of support offered for Obama’s closet Muslim extremism or McCain’s senility, but they were produced in a format that made them look like copies of newspaper articles. After reading one or the other, participants were asked to rate their degree of endorsement of the thesis of the article they read.

Data were analyzed separately for those who had identified as Obama supporters, McCain supporters, or undecided. Care was taken to ensure that the participants knew that the experimenters would not be able to connect the responses to individual participants.

The key manipulation was that a questionnaire about the participants’ demographics, given immediately before the rest of the study, either included or did not include the race question (the same as in experiment 2) or a similar question about participants’ age group.

As expected, declared supporters of each candidate gave low endorsement to the smear of their candidate and higher endorsement to the smear of their candidate’s opponent. A key finding emerged from the results for the undecideds. Those who had received the race question gave higher ratings to the Obama smear than those who had not, and those who had received the age question gave higher ratings to the McCain smear than those who had not. The authors conclude that “It appears that undecided individuals can become motivated to accept smears of multiple candidates when situational factors render intergroup differences salient.” (p. 392)

This experiment is evidence for a sobering result. That one accepts a certain racial classification or a certain age classification as applying to oneself cannot be a reason for accepting or rejecting a smear of a candidate. The race and age of the candidates was well known to everyone. The manipulation consisting of including or not including the self-classification question regarding race or age did not supply new knowledge or a reason. Nonetheless it had an effect. It seems that this effect, therefore, worked through a process that did not engage conscious processing of the kind we would recognize as weighing reasons or evaluating evidence. Thus, this experiment provides evidence that even when inputs (reading and answering the race or age classification question) and outputs (making a mark on a scale indicating endorsement of an article’s thesis) are fully conscious, there can be processes that work outside of consciousness, yet produce effects on the conscious output.

[Kosloff, S., Greenberg, J., Schmader, T., Dechesne, M. and Weise, D. (2010) “Smearing the Opposition: Implicit and Explicit Stigmatization of the 2008 Presidential Candidates and the Current U. S. President”, Journal of Experimental Psychology: General 139(3): 383-398. This paper contains several results not stated here, and a fourth experiment that confirms and extends the results of experiment 3.]


Glimpses of the Unconscious Mind

January 9, 2011

There is a little experiment that I’ve sometimes recommended as a way of appreciating what our brains do unconsciously. It concerns the phenomenon of finding that one has a tune ‘running through one’s head’. Namely, the next time this happens to you, stop and try to think why you has this particular tune in mind right now.

When I’ve tried this, I’ve often had success. What happens is that I’ll recall that a few minutes before I noticed the tune, some key word or phrase from its lyrics happened to occur in a conversation. The conversation was not about the song, or anything closely related to it, and the word or phrase did not trigger any inner speech that had the sense of “Oh, that word/phrase is from <such and such piece of music>.” No: there were several minutes of attending to a conversation on completely unrelated matters, and then “out of the blue” the inner humming of some tune.

(I regret to report that discovery of the explanation for the tune’s running through one’s head does nothing to get rid of its annoying repetition.)

The successes I can recall all worked through the words associated with the tune. But, in his new book, Antonio Damasio reports a more interesting case that worked a little differently. In brief, he found himself thinking of a certain colleague, Dr. B. Damasio had not talked with Dr. B. recently. They were not collaborating on a project, there was no need to see Dr. B., and no plan to do so. Damasio had seen Dr. B. walking by his office window sometime earlier, but that was only remembered later and had not been an object of attention at the time. Damasio wondered why he was thinking of Dr. B.

The explanation that came to mind on reflection was that Damasio had happened, quite unintentionally, to have moved in a way that was similar to Dr. B’s somewhat distinctive gait. Damasio’s explanation is that the accidental circumstance of moving in a way similar to Dr. B. triggered an unconscious process that resulted in Dr. B’s coming to mind.

What makes this case so interesting to me is that, unlike my tune cases, it does not plausibly work through the language system. Of course, I know a few words I could use to describe a person’s gait, but even if I worked hard at it, I think the best I could do would be a vague description that would apply to many people. I suspect it’s the same for most of us. It’s just not believable that Damasio had a verbal description of gait that was specific for Dr. B. And even if he were capable of such a feat of literary skill, he had not been trying to describe his own movement, and so there would have been no route to making a connection by association through words.

What’s left is that the thought of Dr. B. was produced through a process that was not only not conscious, but also not verbal. The memory of Dr. B.’s motion was called up by Damasio’s own motion directly by the similarity of the motions, not through the medium of verbal representations of those motions.

(The suggestion that the motion may not have been accidental, but was caused by Damasio’s having seen his colleague walking by his window, in no way undercuts the point here. For, that would also be a case of unconscious processing leading to, this time, actual movement, without having gone through verbal representations of the stimulus or the resulting motion.)

An attractive analogy for a leading strand in Your Brain and You is that unconscious, nonverbal processing underlies our mental processing in the way that rock strata underlie the ground we walk on. Unless we’re lucky enough to be in a place like the Grand Canyon, we see the strata clearly only occasionally, where there is an outcrop. Damasio’s case seems to me to be one of these outcrops, where we can get a clear glimpse of our unconscious, nonverbal mind at work.

[A. Damasio, Self Comes to Mind: Constructing the Conscious Brain (New York: Pantheon, 2010). The coming to mind of Dr. B. is discussed on pp. 104-106 ]


Explanation and Sensations

December 10, 2010

Readers of Your Brain and You will know that I deny that sensations are identical with neural events. Neural events cause sensations, but the effects are different from their causes. The qualities that distinguish sensations – colors, tastes, smells, itchiness, hunger, and so on are found in the sensations, not in the coordinated groups of neuron firings that cause the sensations.

But I do agree that water is identical with H2O and that the heat in, say, a frying pan, is nothing but the average energy in the motion (or, mean kinetic energy) of the molecules that compose the pan.

So, what is the difference between these two kinds of case? In a nutshell, the identities I accept are backed by explanations, but the alleged identity of sensations and neural events is a bald piece of ideology that is not backed by explanations.

Of course, physicalists, who propose that pain is nothing but neural firing of a certain kind (let’s call it Neural Kind NK1), and having an orange afterimage is nothing but having a neural firing of a different kind (let’s call it NK2) will not take this claim of difference lying down. They’ll say “What do you mean “is backed by an explanation”? And they’ll ask whether there is really any difference in the explanatory value of “water = H2O” and “pain = NK1”.

Those are fair questions, so let’s try to answer them. I’ll address the first one by focusing on just one case, which is representative of many others. Namely, ‘water = H2O” is supported by its explaining why water dissolves salt.

What the chemists tell us is that H2O molecules, in virtue of their chemical properties, can surround individual molecules of salt (i.e., NaCl molecules). So, when we put salt into water, its molecules don’t stay together, they get separated so that H2O molecules lie between the salt molecules. And that’s just what we mean by “dissolves salt”. So, the hypothesis that water = H2O explains why salt dissolves in water. And its giving us access to such an explanation is a reason for accepting the identity of water with H2O. Other cases go similarly, and give us further support.

Well, not so fast! While there’s a good idea expressed here, it won’t do as it stands, because it’s simply not true that “dissolves salt” just means “has its molecules surrounded by molecules of the solvent”. After all, people knew that water dissolves salt long before they had any ideas about molecules. And they knew that it also dissolves sugar, for example, but not gold.

So, how can we rescue the good idea without having to say something that is plainly false? Well, how did people know that water dissolves salt when they didn’t know anything about molecules? They put salt into water and, after a bit of stirring, they couldn’t see it any more. But if they put their wedding ring in water and stirred for a long time, there would be the ring, as plainly visible as when they took it off their finger.

What this example suggests is that a better description of what “water = H2O” explains, in our particular case, is why things look the way they do. When we put salt into water and stir, we can’t see it any more. Given that we can’t see individual molecules, the chemists’ story about what happens when we put salt into water explains why we can’t see it after stirring.

The generalization is that identity claims like “water = H2O”, together with other claims we already accept (such as that we can’t see individual molecules) explains why our evidence is what it is.

Here are a few other examples to illustrate the point. (1) Water evaporates, desks do not. E.g., if there is water on a kitchen counter and we don’t do anything, the counter will be dry a few hours later; but our desks don’t disappear. That’s something we see. Chemists’ stories about strength of bonding and the transfer of kinetic energy explain why we see the dry counter, but don’t lose our desks.

(2) We can put a cool thing up against a warm thing, and feel that the first has gotten warmer after a while. If heat is just the motion energy of molecules, and motion energy can be transferred by contact, we have an explanation of why the cooler body warms up.

(3) It would be a thankless task to try to define “life”. But we can see that things we agree are living typically grow. A strictly biological story (ingestion, digestion, metabolism) explains why organisms get bigger. This supports the idea that living things are nothing but biological systems; and similar explanations of other typical functions converge on the same result.

What about the second question? If “pain  = NK1” were like “water = H2O”, then there being NK1 should explain why some piece of evidence is what it is. No such explanation seems to be in the offing. If “having an orange afterimage = having NK2” were like “heat = mean kinetic energy” there should be some piece of evidence that is explained by NK2. Again, no such explanation seems available. It’s not even clear why any neural event should ever be correlated with any sensation at all.

Physicalists may suggest, however, that such explanations are available. Namely, we see that pains cause pain behavior (e.g., withdrawing, favoring injured parts, avoiding repeated contact with the source of the pain), and we see that having orange afterimages cause reports of their occurrence. “Pain = NK1” and “having an orange afterimage = having NK2” explain these pieces of evidence.

But these causal connections are not pieces of evidence: they are inferred conclusions. Moreover, the inferences depend on assuming the identities. Actions, including utterances of reports, are – as physicalists agree – caused by neural events. The neural events are themselves adequate to bring about the behavior. The causal relevance of pain or having an orange afterimage comes in only by using the identity claims. The pattern is: NK1 causes behavior B, pain = NK1, therefore pain causes behavior B.

It follows that these alleged pieces of evidence cannot be used to support identity claims; for to make such a use would be circular reasoning. The pattern would be this:

[1] pain = NK1

[2] NK1 causes behavior B

[3] Therefore, pain causes behavior B.

[4] We can explain why (or how) pain causes behavior B by assuming that pain = NK1.

[5] We are entitled to identity claims if they are backed by explanations.

[6] Therefore, we are entitled to the identity claim that pain = NK1.

But you can’t get to [3] without assuming [1]; and the legitimacy of that assumption is the conclusion of this reasoning. So this kind of “support” for “pain = NK1” depends on assuming what was to be supported.

Even those who think that “pain = NK1” or “having an orange afterimage = NK2” are true ought to be able to see that such claims cannot be supported in a way that parallels our reasons for accepting “water is H2O”, “heat is mean kinetic energy” and similar identity claims.