The burden of skepticism, by: Carl Sagan

The Burden of Skepticism 
by Carl Sagan 
first published in Skeptical Inquirer, vol. 12 (1), Fall 1987, pp: 38-46

What is Skepticism? It's nothing very esoteric. We encounter it every day. When we buy a used car, if we are the least bit wise we will exert some residual skeptical powers -- whatever our education has left to us. You could say, "Here's an honest-looking fellow. I'll just take whatever he offers me." Or you might say, "Well, I've heard that occasionally there are small deceptions involved in the sale of a used car, perhaps inadvertent on the part of the salesperson," and then you do something. You kick the tires, you open the doors, you look under the hood. (You might go through the motions even if you don't know what is supposed to be under the hood, or you might bring a mechanically inclined friend.) You know that some skepticism is required, and you understand why. It's upsetting that you might have to disagree with the used-car salesman or ask him questions that he is reluctant to answer. There is at least a small degree of interpersonal confrontation involved in the purchase of a used car and nobody claims it is especially pleasant. But there is a good reason for it -- because if you don't exercise some minimal skepticism, if you have an absolutely untrammeled credulity, there is probably some price you will have to pay later. Then you'll wish you had made a small investment of skepticism early.

Now this is not something that you have to go through four years of graduate school to understand. Everybody understands this. The trouble is, a used car is one thing but television commercials or pronouncements by presidents and party leaders another. We are skeptical in some areas but unfortunately not in others.

For example, there is a class of aspirin commercials that reveals the competing product to have only so much of the painkilling ingredient that doctors recommend most -- they don't tell you what the mysterious ingredient is -- whereas their product has a dramatically larger amount (1.2 to 2 times more per tablet). Therefore you should buy their product. But why not just take two of the competing tablets? You're not supposed to ask. Don't apply skepticism to this issue. Don't think. Buy.

Such claims in commercial advertisements constitute small deceptions. They part us from a little money, or induce us to buy a slightly inferior product. It's not so terrible. But consider this:

I have here the program of this year's Whole Life Expo in San Francisco. Twenty thousand people attended last year's program. Here are some of the presentations: "Alternative Treatments for AIDS Patients: it will rebuild one's natural defenses and prevent immune system breakdowns -- learn about the latest developments that the media has thus far ignored." It seems to me that presentation could do real harm. "How Trapped Blood Proteins Produce Pain and Suffering." "Crystals, Are They Talismans or Stones?" (I have an opinion myself) It says, "As a crystal focuses sound and light waves for radio and television" crystal sets are rather a long time ago -- "so may it amplify spiritual vibrations for the attuned human." I'll bet very few of you are attuned. Or here's one: "Return of the Goddess, a Presentational Ritual." Another: "Synchronicity, the Recognition Experience." That one is given by "Brother Charles. Or, on the next page, "You, Saint-Germain, and Healing Through the Violet Flame." It goes on and on, with lots of ads about "opportunities" -- ranging from the dubious to the spurious -- that are available at the Whole Life Expo.

If you were to drop down on Earth at any time during the tenure of humans you would find a set of popular, more or less similar, belief systems. They change, often very quickly, often on time scales of a few years: But sometimes belief systems of this sort last for many thousands of years. At least a few are always available. I think it's fair to ask why. We are Homo sapiens. That's the distinguishing characteristic about us, that sapiens part. We're supposed to be smart. So why is this stuff always with us? Well, for one thing, a great many of these belief systems address real human needs that are not being met by our society. There are unsatisfied medical needs, spiritual needs, and needs for communion with the rest of the human community. There may be more such failings in our society than in many others in human history. And so it is reasonable for people to poke around and try on for size various belief systems, to see if they help.

For example, take a fashionable fad, channeling. It has for its fundamental premise, as does spiritualism, that when we die we don't exactly disappear, that some part of us continues. That part, we are told, can reenter the bodies of human and other beings in the future, and so death loses much of its sting for us personally. What is more, we have an opportunity, if the channeling contentions are true, to make contact with loved ones who have died.

Speaking personally, I would be delighted if reincarnation were real. I lost my parents, both of them, in the past few years, and I would love to have a little conversation with them, to tell them what the kids are doing, make sure everything is all right wherever it is they are. That touches something very deep. But at the same time, precisely for that reason, I know that there are people who will try to take advantage of the vulnerabilities of the bereaved. The spiritualists and the channelers better have a compelling case.

Or take the idea that by thinking hard at geological formations you can tell where mineral or petroleum deposits are. Uri Geller makes this claim. Now if you are an executive of a mineral exploration or petroleum company, your bread and butter depend on finding the minerals or the oil: so spending trivial amounts of money, compared with what you usually spend on geological exploration, this time to find deposits psychically, sounds not so bad. You might be tempted.

Or take UFOS, the contention that beings in spaceships from other worlds are visiting us all the time. I find that a thrilling idea. It's at least a break from the ordinary. I've spent a fair amount of time in my scientific life working on the issue of the search for extraterrestrial intelligence. Think how much effort I could save if those guys are coming here. But when we recognize some emotional vulnerability regarding a claim, that is exactly where we have to make the firmest efforts at skeptical scrutiny. That is where we can be had.

Now, let's reconsider channeling. There is a woman in the State of Washington who claims to make contact with a 35,000-year-old somebody, "Ramtha" -- she, by the way, speaks English very well with what sounds to me to be an Indian accent. Suppose we had Ramtha here and just suppose Ramtha is cooperative. We could ask some questions: How do we know that Ramtha lived 35,000 years ago? Who is keeping track of the intervening millennia? How does it come to be exactly 35,000 years? That's a very round number. Thirty-five thousand plus or minus what? What were things like 35,000 years ago? What was the climate? Where on Earth did Ramtha live? (I know he speaks English with an Indian accent, but where was that?) What does Ramtha eat? (Archaeologists know something about what people ate back then.) We would have a real opportunity to find out if his claims are true. If this were really somebody from 35,000 years ago, you could learn a lot about 35,000 years ago. So, one way or another, either Ramtha really is 35,000 years old, in which case we discover something about that period -- that's before the Wisconsin Ice Age, an interesting time -- or he's a phony and he'll slip up. What are the indigenous languages, what is the social structure, who else does Ramtha live with -- children, grandchildren -- what's the life cycle, the infant mortality, what clothes does he wear, what's his life expectancy, what are the weapons, plants, and animals? Tell us. Instead, what we hear are the most banal homilies, indistinguishable from those that alleged UFO occupants tell the poor humans who claim to have been abducted by them.

Occasionally, by the way, I get a letter from someone who is in "contact" with an extraterrestrial who invites me to "ask anything." And so I have a list of questions. The extraterrestrial are very advanced, remember. So I ask things like, "Please give a short proof of Fermat's Last Theorem." Or the Goldbach Conjecture. And then I have to explain what these are, because extraterrestrials will not call it Fermat's Last Theorem, so I write out the little equation with the exponents. I never get an answer. On the other hand, if I ask something like "Should we humans be good?" I always get an answer. I think something can be deduced from this differential ability to answer questions. Anything vague they are extremely happy to respond to, but anything specific, where there is a chance to find out if they actually know anything, there is only silence.

The French scientist Henri Poincar6 remarked on why credulity is rampant: "We also know how cruel the truth often is, and we wonder whether delusion is not more consoling." That's what I have tried to say with my examples. But I don't think that's the only reason credulity is rampant. Skepticism challenges established institutions. If we teach everybody, let's say high school students, the habit of being skeptical, perhaps they will not restrict their skepticism to aspirin commercials and 35,000-year-old channelers (or channelees). Maybe they'll start asking awkward questions about economic, or social, or political, or religious institutions. Then where will we be?

Skepticism is dangerous. That's exactly its function, in my view. It is the business of skepticism to be dangerous. And that's why there is a great reluctance to teach it in the schools. That's why you don't find a general fluency in skepticism in the media. On the other hand, how will we negotiate a very perilous future if we don't have the elementary intellectual tools to ask searching questions of those nominally in charge, especially in a democracy?

I think this is a useful moment to reflect on the sort of national trouble that could have been avoided were skepticism more generally available in American society. The Iran/Nicaragua fiasco is so obvious an example I will not take advantage of our poor, beleaguered president [Reagan] by spelling it out. The Administration's resistance to a Comprehensive Test Ban Treaty and its continuing passion for blowing up nuclear weapons -- one of the major drivers of the nuclear arms race -- under the pretense of making us "safe" is another such issue. So is Star Wars. The habits of skeptical thought CSICOP encourages have relevance for matters of the greatest importance to the nation. There is enough nonsense promulgated by both political parties that the habit of evenhanded skepticism should be declared a national goal, essential for our survival.

I want to say a little more about the burden of skepticism. You can get into a habit of thought in which you enjoy making fun of all those other people who don't see things as dearly as you do. This is a potential social danger present in an organization like CSICOR. We have to guard carefully against it.

It seems to me what is called for is an exquisite balance between two conflicting needs: the most skeptical scrutiny of all hypotheses that are served up to us and at the same time a great openness to new ideas. Obviously those two modes of thought are in some tension. But if you are able to exercise only one of these modes, whichever one it is, you're in deep trouble.

If you are only skeptical, then no new ideas make it through to you. You never learn anything new. You become a crotchety old person convinced that nonsense is ruling the world. (There is, of course, much data to support you.) But every now and then, maybe once in a hundred cases, a new idea turns out to be on the mark, valid and wonderful. If you are too much in the habit of being skeptical about everything, you are going to miss or resent it, and either way you will be standing in the way of understanding and progress.

On the other hand, if you are open to the point of gullibility and have not an ounce of skeptical sense in you, then you cannot distinguish the useful as from the worthless ones. If all ideas have equal validity then you are lost, because then, it seems to me, no ideas have any validity at all.

Some ideas are better than others. The machinery for distinguishing them is an essential tool in dealing with the world and especially in dealing with the future. And it is precisely the mix of these two modes of thought that is central to the success of science.

Really good scientists do both. On their own, talking to themselves, they churn up huge numbers of new ideas and criticize them ruthlessly. Most of the ideas never make it to the outside world. Only the ideas that pass through rigorous self-filtration make it out and are criticized by the rest of the scientific community. It sometimes happens that ideas that are accepted by everybody turn out to be wrong, or at least partially wrong, or at least superseded by ideas of greater generality. And, while there are of course some personal losses -- emotional bonds to the idea that you yourself played a role inventing -- nevertheless the collective ethic is that every time such an idea is overthrown and replaced by something better the enterprise of science has benefited. In science it often happens that scientists say, "You know that's a really good argument; my position is mistaken," and then they actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. 1 cannot recall the last time something like that has happened in politics or religion. It's very rare that a senator, say, replies, "That's a good argument. I will now change by political affiliation."

I would like to say a few things about the stimulating sessions on the search for extraterrestrial intelligence (SETI) and on animal language at our CSICOP conference. In the history of science there is an instructive procession for major intellectual battles that turn out, all of them, to be about how central human beings are. We could call them battles about the anti-Copernican conceit.

Here are some of the issues:

We are the center of the Universe. All the planets and the stars and the Sun and the Moon go around us. (Boy, must we be something really special.) That was the prevailing belief -- Aristarchus aside -- until the time of Copernicus. A lot of people liked it because it gave them a personally unwarranted central position in the Universe. The mere fact that you were on Earth made you privileged. That felt good. Then along came the evidence that Earth was just a planet and that those other bright moving points of light were planets too. Disappointing. Even depressing. Better when we were central and unique.

• But at least our Sun is at the center of the Universe. No, those other stars, they're suns too, and what's more we're out in the galactic boondocks. We are nowhere near the center of the Galaxy. Very depressing.
   
• Well, at least the Milky Way galaxy is at the center of the Universe. Then a little more progress in science. We find there isn't any such thing as the center of the Universe. What's more there are a hundred billion other galaxies. Nothing special about this one. Deep gloom.
   
• Well, at least we humans, we are the pinnacle of creation. We're separate. All those other creatures, plants and animals, they're lower. We're higher. We have no connection with them. Every living thing has been created separately. Then along comes Darwin. We find an evolutionary continuum. We're closely connected to the other beasts and vegetables. What's more, the closest biological relatives to us are chimpanzees. Those are our close relatives -- those guys? It's an embarrassment. Did you ever go to the zoo and watch them? Do you know what they do? Imagine in Victorian England, when Darwin produced this insight, what an awkward truth it was.

There are other important examples -- privileged reference frames in physics and the unconscious mind in psychology -- that I'll pass over.

I maintain that in the tradition of this long set of debates -- very one of which was won by the Copernicans, by the guys who say there is not much special about us -- there was a deep emotional undercurrent in the debates in both CSICOP sessions I mentioned. The search for extraterrestrial intelligence and the analysis of possible animal "language" strike at one of the last remaining pre-Copernican belief systems:

• At least we are the most intelligent creatures in the whole Universe. If there are no other smart guys elsewhere, even if we are connected to chimpanzees, even if we are in the boondocks of a vast and awesome universe, at least there is still something special about us. But the moment we find extraterrestrial intelligence that last bit of conceit is gone. I think some of the resistance to the idea of extraterrestrial intelligence is due to the anti-Copernican conceit. Likewise, without taking sides in the debate on whether other animals -- higher primates, especially great apes -- are intelligent or have language, that's clearly, on an emotional level, the same issue. If we define humans as creatures who have language and no one else has language, at least we are unique in that regard. But if it turns out that all those dirty, repugnant, laughable chimpanzees can also, with Ameslan or otherwise, communicate ideas, then what is left that is special about us? Propelling emotional predispositions on these issues are present, often unconsciously, in scientific debates. It is important to realize that scientific debates, just like pseudoscientific debates, can be awash with emotion, for these among many different reasons.

Now, let's take a closer look at the radio search for extraterrestrial intelligence. How is this different from pseudoscience? Let me give a couple of real cases. In the early sixties, the Soviets held a press conference in Moscow in which they announced that a distant radio source, called CTA-102, was varying sinusoidally, like a sine wave, with a period of about 100 days. Why did they call a press conference to announce that a distant radio source was varying? Because they thought it was an extraterrestrial civilization of immense powers. That is worth calling a press conference for. This was before even the word "quasar" existed. Today we know that CTA-102 is a quasar. We don't know very well what quasars are: and there is more than one mutually exclusive explanation for them in the scientific literature. Nevertheless, few seriously consider that a quasar, like CTA-102, is some galaxygirdling extraterrestrial civilization, because there are a number of alternative explanations of their properties that are more or less consistent with the physical laws we know without invoking alien life. The extraterrestrial hypothesis is a hypothesis of last resort. Only if everything else fails do you reach for it.

Second example: British scientists in 1967 found a nearby bright radio source that is fluctuating on a much shorter time scale, with a period constant to ten significant figures. What was it? Their first thought was that it was something like a message being sent to us, or an interstellar navigational beacon for spacecraft that fly the spaces between the stars. They even gave it, among themselves at Cambridge University, the wry designation LGM-1-Little Green Men, LGM. However (they were wiser than the Soviets), they did not call a press conference, and it soon became clear that what we had here was what is now called a "pulsar." In fact it was the first pulsar, the Crab Nebula pulsar. Well, what's a pulsar? A pulsar is a star shrunk to the size of a city, held up as no other stars are, not by gas pressure, not by electron degeneracy, but by nuclear forces. It is in a certain sense an atomic nucleus the size of Pasadena. Now that, I maintain, is an idea at least as bizarre as an interstellar navigational beacon. The answer to what a pulsar is has to be something mighty strange. It isn't an extraterrestrial civilization, it's something else: but a something else that opens our eyes and our minds and indicates possibilities in nature that we had never guessed at.

Then there is the question of false positives. Frank Drake in his original Ozma experiment, Paul Horowitz in the META (Megachannel Extraterrestrial Assay) program sponsored by the Planetary Society, the Ohio University group and many other groups have all had anomalous signals that make the heart palpitate. They think for a moment that they have picked up a genuine signal. In some cases we have not the foggiest idea what it was; the signals did not repeat. The next night you turn the same telescope to the same spot in the sky with the same modulation and the same frequency and band pass everything else the same, and you don't hear a thing. You don't publish that data. It may be a malfunction in the detection system. It may be a military AWACS plane flying by and broadcasting on frequency channels that are supposed to be reserved for radio astronomy. It may be a diathermy machine down the street. There are many possibilities. You don't immediately declare that you have found extraterrestrial intelligence because you find an anomalous signal.

And if it were repeated, would you then announce? You would not. Maybe it's a hoax. Maybe it is something you haven't been smart enough to figure out that is happening to your system. Instead, you would then call scientists at a bunch of other radio telescopes and say that at this particular spot in the sky, at this frequency and bandpass and modulation and all the rest, you seem to be getting something funny. Could they please look at it and see if they got something similar? And only if several independent observers get the same kind of information from the same spot in the sky do you think you have something. Even then you don't know that the something is extraterrestrial intelligence, but at least you could determine that it's not something on Earth. (And that it's also not something in Earth orbit; it's further away than that.) That's the first sequence of events that would be required to be sure that you actually had a signal from an extraterrestrial civilization.

Now notice that there is a certain discipline involved. Skepticism imposes a burden. You can't just go off shouting "little green men," because you are going to look mighty silly, as the Soviets did with CTA-102, when it turns out to be something quite different. A special caution is necessary when the stakes are as high as here. We are not obliged to make up our minds before the evidence is in. It's okay not to be sure.

I'm often asked the question, "Do you think there is extraterrestrial intelligence?" I give the standard arguments -- there are a lot of places out there, and use the word billions, and so on. And then I say it would be astonishing to me if there weren't extraterrestrial intelligence, but of course there is as yet no compelling evidence for it. And then I'm asked, "Yeah, but what do you really think?" I say, "I just told you what I really think." "Yeah, but what's your gut feeling?" But I try not to think with my gut. Really, it's okay to reserve judgment until the evidence is in.

After my article "The Fine Art of Baloney Detection" came out in Parade (Feb. 1, 1987), he got, as you might imagine, a lot of letters. Sixty-five million people read Parade. In the article I gave a long list of things that I said were "demonstrated or presumptive baloney' -- thirty or forty items. Advocates of all those positions were uniformly offended, so I got lots of letters. I also gave a set of very elementary prescriptions about how to think about baloney -- arguments from authority don't work, every step in the chain of evidence has to be valid, and so on. Lots of people wrote back, saying, "You're absolutely right on the generalities; unfortunately that doesn't apply to my particular doctrine." For example, one letter writer said the idea that intelligent life exists outside the earth is an excellent example of baloney. He concluded, "I am as sure of this as of anything in my experience. There is no conscious life anywhere else in the Universe. Mankind thus returns to its rightful position as center of the Universe."

Another writer again agreed with all my generalities, but said that as an inveterate skeptic I have closed my mind to the truth. Most notably I have ignored the evidence for an Earth that is six thousand years old. Well, I haven't ignored it; I considered the purported evidence and then rejected it. There is a difference, and this is a difference, we might say, between prejudice and postjudice. Prejudice is making a judgment before you have looked at the facts. Postjudice is making a judgment afterwards. Prejudice is terrible, in the sense that you commit injustices and you make serious mistakes. Postjudice is not terrible. You can't be perfect of course; you may make mistakes also. But it is permissible to make a judgment after you have examined the evidence. In some circles it is even encouraged.

I believe that part of what propels science is the thirst for wonder. It's a very powerful emotion. All children feel it. In a first grade classroom everybody feels it; in a twelfth grade classroom almost nobody feels it, or at least acknowledges it. Something happens between first and twelfth grade, and it's not just puberty. Not only do the schools and the media not teach much skepticism, there is also little encouragement of this stirring sense of wonder. Science and pseudoscience both arouse that feeling. Poor popularizations of science establish an ecological niche for pseudoscience.

If science were explained to the average person in a way that is accessible and exciting, there would be no room for pseudoscience. But there is a kind of Gresham's Law by which in popular culture the bad science drives out the good. And for this I think we have to blame, first, the scientific community ourselves for not doing a better job of popularizing science, and second, the media, which are in this respect almost uniformly dreadful. Every newspaper in America has a daily astrology column. How many have even a weekly astronomy column? And I believe it is also the fault of the educational system. We do not teach how to think. This is a very serious failure that may even, in a world rigged with 60,000 nuclear weapons, compromise the human future.

I maintain there is much more wonder in science than in pseudoscience. And in addition, to whatever measure this term has any meaning, science has the additional virtue, and it is not an inconsiderable one, of being true.

Reading is SEXy

Tuesday, July 17, 2007

Leer es SEXy

Pay-per-reading society: Asda says Harry Potter's Bloombury publisher is "profiteering"

Asda says Potter publisher "profiteering"

Tue Jul 17, 2007 12:02PM BST

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By Mike Collett-White

LONDON (Reuters) - The publisher of the Harry Potter books called in the lawyers after a supermarket chain accused it of "blatant profiteering" for charging 17.99 pounds for the final novel in the series.

The dispute between Bloomsbury and Asda, the British unit of Wal-Mart Stores, erupted on Tuesday, just four days before the launch of "Harry Potter and the Deathly Hallows", widely expected to become the fastest selling book of all time.

Bloomsbury said it cancelled a delivery of 500,000 copies to Asda stores across the country because of unpaid bills.

But Asda believes the real reason is a statement it issued on Sunday in which it criticised Bloomsbury's pricing policy.

"Today, Asda pointed the finger directly at Bloomsbury for attempting to hold children to ransom by raising the recommended retail price on the final Harry Potter instalment," it said, adding that the pricing was "blatant profiteering".

The retail price of 17.99 for "Deathly Hallows" compares with 11.99 pounds for "Harry Potter and the Philosopher's Stone", the first book in the series published 10 years ago.

That book was 223 pages long, compared with 608 pages for the seventh and last instalment.

A spokeswoman for Asda confirmed that the company had received a legal letter from Bloomsbury on Tuesday, and that its own legal team was working out what to do in response. Continued...

"It seems Bloomsbury doesn't like us suggesting the publishers might be profiteering from the sale of the last book in the series," she said.

Asda hopes the issue can be resolved in time for a delivery of the books to its stores ahead of a deadline in the first minute of Saturday morning, when stores around the country will be allowed to begin selling the book.

Bloomsbury said the row started over "invoicing arrears", but escalated after the release of the Asda statement.

"It did start with the invoicing arrears, but you can't escape from the fact that this press release is extremely provocative, and I think potentially libellous," Bloomsbury marketing director Minna Fry said.

"Asda definitely owes us money and this has been going back for years," she told BCC Radio's Today programme.

"When you don't pay your electricity bill you get cut off, they don't just say, 'Oh, we'll wait and see if you perhaps pay up.' They will remain cut off."

She also defended the increase in Potter book prices.

"That was 10 years ago and that was around 200 pages," said Fry, referring to the "Philosopher's Stone".

"This is 608 pages long ... 17.99 is in line with other hardback novels of this length." Continued...

Asda has taken online pre-orders for "Deathly Hallows" for 8.87 pounds, and will reveal its in-store price on Friday.

Asda, rival supermarket chains and online retailers have launched an aggressive price war over the final Potter, likely to sell tens of millions of copies worldwide. Small, independent booksellers have been squeezed out of the market as a result.

Emotions not necessary to make moral judgements. Nature, March 21, 2007

Letter

Nature advance online publication 21 March 2007 | doi:10.1038/nature05631; Received 3 November 2006; Accepted 17 February 2007; Published online 21 March 2007

Damage to the prefrontal cortex increases utilitarian moral judgements

Michael Koenigs^1,5,6, Liane Young^2,6, Ralph Adolphs^1,3, Daniel Tranel¹, Fiery Cushman², Marc Hauser² and Antonio Damasio^1,4

1. Department of Neurology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242, USA
2. Department of Psychology, Harvard University, Cambridge, Massachusetts 02138, USA
3. Division of Humanities and Social Sciences and Division of Biology, California Institute of Technology, Pasadena, California 91125, USA
4. Brain and Creativity Institute and Dornsife Center for Cognitive Neuroimaging, University of Southern California, Los Angeles, California 90089, USA
5. Present address: National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892-1440, USA.
6. These authors contributed equally to this work.

Correspondence to: Ralph Adolphs^1,3 Correspondence and requests for materials should be addressed to R.A. (Email: radolphs@hss.caltech.edu).

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Abstract

The psychological and neurobiological processes underlying moral judgement have been the focus of many recent empirical studies^{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11}. Of central interest is whether emotions play a causal role in moral judgement, and, in parallel, how emotion-related areas of the brain contribute to moral judgement. Here we show that six patients with focal bilateral damage to the ventromedial prefrontal cortex (VMPC), a brain region necessary for the normal generation of emotions and, in particular, social emotions^{12, 13, 14}, produce an abnormally 'utilitarian' pattern of judgements on moral dilemmas that pit compelling considerations of aggregate welfare against highly emotionally aversive behaviours (for example, having to sacrifice one person's life to save a number of other lives)^{7, 8}. In contrast, the VMPC patients' judgements were normal in other classes of moral dilemmas. These findings indicate that, for a selective set of moral dilemmas, the VMPC is critical for normal judgements of right and wrong. The findings support a necessary role for emotion in the generation of those judgements.

The basis of our moral judgements has been a long-standing focus of philosophical inquiry and, more recently, active empirical investigation. In a departure from traditional rationalist approaches to moral cognition that emphasize the role of conscious reasoning from explicit principles¹⁵, modern accounts have proposed that emotional processes, conscious or unconscious, may also play an important role^{16, 17}. Emotion-based accounts draw support from multiple lines of empirical work: studies of clinical populations reveal an association between impaired emotional processing and disturbances in moral behaviour^{1, 2, 3, 4}; neuroimaging studies consistently show that tasks involving moral judgement activate brain areas known to process emotions^{5, 6, 7, 8, 9}; and behavioural studies demonstrate that manipulation of affective state can alter moral judgements^{10, 11}. However, neuroimaging studies do not settle whether putatively 'emotional' activations are a cause or consequence of moral judgement; behavioural studies in healthy individuals do not address the neural basis of moral judgement; and no clinical studies have specifically examined the moral judgements (as opposed to moral reasoning or moral behaviour) of patients with focal brain lesions. In brief, none of the existing studies establishes that brain areas integral to emotional processes are necessary for the generation of normal moral judgements. As a result, there remains a critical gap in the evidence relating moral judgement, emotion and the brain.

Investigating moral judgements in individuals with focal damage to the ventromedial prefrontal cortex (VMPC) provides a key test. The VMPC projects to basal forebrain and brainstem regions that execute bodily components of emotional responses¹⁸, and neurons within the VMPC encode the emotional value of sensory stimuli¹⁹. Patients with VMPC lesions exhibit generally diminished emotional responsivity and markedly reduced social emotions (for example, compassion, shame and guilt) that are closely associated with moral values^{1, 2, 12, 13, 14, 16}, and also exhibit poorly regulated anger and frustration tolerance in certain circumstances^{20, 21}. Despite these patent defects both in emotional response and emotion regulation, the capacities for general intelligence, logical reasoning, and declarative knowledge of social and moral norms are preserved^{20, 21, 22, 23}. We selected a sample of six patients with adult-onset, focal bilateral VMPC lesions (Fig. 1) as well as both neurologically normal (NC) and brain-damaged comparison (BDC) subjects. Importantly, each of the VMPC patients had striking defects in social emotion but generally intact intellect and normal baseline mood (Tables 1 and 2, see also Supplementary Table 1). In particular, all six VMPC patients had impaired autonomic activity in response to emotionally charged pictures (Table 2), as well as severely diminished empathy, embarrassment and guilt (Table 2). All comparison subjects (NC and BDC) had intact emotional processing.

Figure 1: Lesion overlap of VMPC patients.

Lesions of the six VMPC patients displayed in mesial views and coronal slices. The colour bar indicates the number of overlapping lesions at each voxel.

High resolution image and legend (364K)

Table 1: VMPC patient neuropsychological data

Full table

Table 2: VMPC patient social emotion data

Full table

Subjects evaluated moral dilemmas designed to pit two competing considerations against one another. A paradigmatic dilemma of this type presents subjects with the choice of whether or not to sacrifice one person's life to save the lives of others. One consideration is a utilitarian calculation of how to maximize aggregate welfare, whereas the other is a strong emotional aversion to the proposed action. One model holds that endorsement of the proposed action (the utilitarian response) requires the subject to overcome an emotional response against inflicting direct harm to another person (a 'personal' harm^{7, 8}). If emotional responses mediated by VMPC are indeed a critical influence on moral judgement, individuals with VMPC lesions should exhibit an abnormally high rate of utilitarian judgements on the emotionally salient, or 'personal', moral scenarios (for example, pushing one person off a bridge to stop a runaway boxcar from hitting five people), but a normal pattern of judgements on the less emotional, or 'impersonal', moral scenarios (for example, turning a runaway boxcar away from five people but towards one person). If, alternatively, emotion does not play a causal role in the generation of moral judgements but instead follows from the judgements^{24, 25}, then individuals with emotion defects due to VMPC lesions should show a normal pattern of judgements on all scenarios.

To test for between-group differences in the probability of utilitarian responses given for each scenario type (non-moral, impersonal moral, personal moral), we used a logistic regression fitted with the generalized estimating equations method (Fig. 2). There were no significant differences between groups on the non-moral or impersonal moral scenarios (all P values >0.29, corrected for multiple comparisons). In contrast, for personal moral scenarios, the VMPC group was more likely to endorse the proposed action than either the NC group (odds ratio = 2.81; P = 0.04, corrected) or BDC group (odds ratio = 3.30; P = 0.006, corrected). There was no difference between the NC and BDC groups (odds ratio = 0.85; P = 0.68, uncorrected). These data indicate that the VMPC group's responses differed only for personal moral scenarios, suggesting that VMPC-mediated processes affect only those moral judgements involving emotionally salient actions.

Figure 2: Moral judgements for each scenario type.

Proportions of 'yes' judgements are shown for each subject group. Error bars indicate 95% confidence intervals. We used three classes of stimuli: non-moral scenarios (n = 18), impersonal moral scenarios (n = 11), and personal moral scenarios (n = 21). On personal moral scenarios, the frequency of endorsing 'yes' responses was significantly greater in the VMPC group than in either comparison group (P values <>High resolution image and legend (59K)

In a more fine-grained analysis, we examined response patterns within the personal moral scenarios. For seven out of the 21 personal moral scenarios, both comparison groups were at 100% agreement in their judgements. An additional eighth scenario elicited 100% agreement from the BDC group, and near-perfect agreement from the NC group (with only one participant deviating from the shared response). These eight scenarios were therefore classified as 'low-conflict' (for example, abandoning one's baby to avoid the burden of caring for it). The remaining 13 scenarios (none of which elicited 100% agreement from either comparison group) were classified as 'high-conflict' (for example, smothering one's baby to save a number of people). Reaction-time data support this distinction: response latencies in the NC group on high-conflict scenarios were significantly longer than on low-conflict scenarios (t-test with 19 degrees of freedom, t(19) = -3.63; P = 0.002).

Like the patients in the comparison groups, the VMPC patients uniformly rejected the proposed action in every one of the low-conflict scenarios (Fig. 3). In contrast, significant differences emerged for the high-conflict scenarios: the VMPC group was more likely to endorse the proposed action than either the NC (odds ratio = 4.70; P = 0.05, corrected) or BDC group (odds ratio = 5.38; P = 0.02, corrected), with no difference between the NC and BDC participants (odds ratio = 0.87; P = 0.77, uncorrected). Every high-conflict personal scenario elicited the same pattern: a greater proportion of the VMPC group endorsed the action than either comparison group.

Figure 3: Moral judgements on individual personal moral scenarios.

Proportions of 'yes' judgements given by each subject group for each of the 21 personal moral scenarios. Individual scenarios (numbered 1–21 on the x axis) are ordered by increasing proportion of 'yes' responses given by the normal comparison group. Responses did not differ between subject groups for the low-conflict scenarios (left of the vertical line). The VMPC group made a greater proportion of 'yes' judgements than either comparison group for every one of the high-conflict scenarios (right of the vertical line).

High resolution image and legend (59K)

To recapitulate, VMPC patients' judgements differed from comparison subjects' only for the high-conflict personal moral dilemmas, all of which featured competing considerations of aggregate welfare on the one hand, and, on the other hand, harm to others that would normally evoke a strong social emotion. Low-conflict personal moral scenarios lacked this degree of competition. This difference probably accounts for the greater consensus and faster reaction times on low-conflict personal dilemmas in the comparison groups, and it can also account for the VMPC patients' pattern of judgements. Evidence suggests that knowledge of explicit social and moral norms is intact in individuals with VMPC damage^{21, 22}. In the absence of an emotional reaction to harm of others in personal moral dilemmas, VMPC patients may rely on explicit norms endorsing the maximization of aggregate welfare and prohibiting the harming of others. This strategy would lead VMPC patients to a normal pattern of judgements on low-conflict personal dilemmas but an abnormal pattern of judgements on high-conflict personal dilemmas, precisely as was observed. The specificity of this result argues against a general deficit in the capacity for moral judgement following VMPC damage. Rather, VMPC seems to be critical only for moral dilemmas in which social emotions play a pivotal role in resolving moral conflict^{4, 8, 16, 17}.

It is important to note that the effects of VMPC damage on emotion processing depend on context. In this study, the VMPC patients' abnormally high rate of utilitarian judgements is attributed to diminished social emotion, whereas in a recent study of the Ultimatum Game, theVMPC patients' abnormally high rate of rejection of unfair monetary offers was attributed to poorly controlled frustration, manifested as exaggerated anger²⁰. These seemingly contradictory findings highlight two distinct aspects of emotion impairment that are due to VMPC damage. In most circumstances, VMPC patients exhibit generally blunted affect and a specific defect of social emotions, but in response to direct personal frustration or provocation, VMPC patients may exhibit short-temper, irritability, and anger. In the moral judgement task we report here, participants respond to hypothetical actions and outcomes that elicit social emotions related to concern for others. In the Ultimatum Game, in contrast, participants respond to unfair take-it-or-leave-it offers that trigger frustration. In brief, the tasks in the two studies are different in that the Ultimatum Game involves self-interest in a real behavioural setting, whereas the task in the present study focuses on the interest of others described in a hypothetical scenario.

To conclude, the present findings are consistent with a model in which a combination of intuitive/affective and conscious/rational mechanisms operate to produce moral judgements^{8, 22, 24, 25, 26, 27}. Though the precise characterization of these potential systems awaits further work, the current results suggest that the VMPC is a critical neural substrate for the intuitive/affective but not for the conscious/rational system.

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Methods

Subjects

Six patients with bilateral, adult-onset damage to the VMPC and twelve brain-damaged comparison patients who had lesions that excluded structures thought to be important for emotions (VMPC, amygdala, insula, right somatosensory cortices) were recruited from the Patient Registry of the Division of Cognitive Neuroscience at the University of Iowa. Twelve healthy comparison subjects with no brain damage were recruited from the Iowa community. Groups were age-, gender- and ethnicity-matched. All participants gave written informed consent.

Neuroanatomical analysis

The neuroanatomical analysis of VMPC patients (Fig. 1) was based on magnetic resonance data for two subjects (those with lesions due to the surgical resection of orbital meningiomas) and on computerized tomography data for the other four subjects (with lesions due to rupture of an anterior communicating artery aneurysm). All neuroimaging data were obtained in the chronic epoch. Each patient's lesion was reconstructed in three dimensions using Brainvox²⁸. Using the MAP-3 technique, the lesion contour for each patient was manually warped into a normal template brain. The overlap of lesions in this volume, calculated by the sum of n lesions overlapping on any single voxel, is colour-coded in Fig. 1.

Stimuli and task

Participants made judgements on a series of 50 hypothetical scenarios, which were adapted from a previously published set⁸. See the Supplementary Information for the full text of the actual scenarios used. Each scenario was presented as text through a series of three screens. The first two described the scenario and the third posed a question about a hypothetical action related to the scenario ("Would you...in order to...?"). Participants read and responded at their own pace, pressing an 'up' arrow key to advance from one screen to the next, and a 'yes' or 'no' button to indicate an answer to the question. 'Yes' responses always indicated commission of the proposed action. There was no time limit for reading the scenario description (screens 1 and 2). Participants had a maximum of 25 s to read the final question screen and respond.

We used three classes of stimuli: non-moral scenarios (n = 18), and two classes of moral scenarios subdivided according to the emotional reaction elicited by the proposed action: 'personal' (n = 21) or 'impersonal' (n = 11), as described previously^{7, 8}. To validate this subdivision, an independent group of ten neurologically normal subjects rated the emotional salience of the actions proposed in the moral scenarios. The actions described in personal scenarios were rated as significantly more emotionally salient than the actions described in impersonal scenarios (means were 5.9 and 3.0 on a scale from 1 to 7, respectively; t(31) = -8.90, P <>

We further subdivided the personal moral scenarios into 'low-conflict' and 'high-conflict' on the basis of the reaction times and consensus produced on them by normal subjects. Reaction times on high-conflict scenarios were significantly longer than on low-conflict scenarios (t(19) = -3.63, P = 0.002). Importantly, low-conflict and high-conflict scenarios did not differ in their rated emotional salience (t(19) = -0.85, P = 0.41).

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References

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Supplementary Information

Supplementary information accompanies this paper.

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Acknowledgements

We thank H. Damasio for making available neuroanatomical analyses of lesion patients and for preparing Fig. 1. We thank all participants for their participation in the experiments and R. Saxe for comments on the manuscript. This work was supported by grants from the National Institutes of Health, the National Science Foundation, the Gordon and Betty Moore Foundation, and the Guggenheim Foundation.

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Impaired emotional processing affects moral judgements

• 13:07 22 March 2007
• NewScientist.com news service
• Roxanne Khamsi

Mr Spock, the fictional Vulcan famously logical and lacking in emotion, sacrificed himself for his comrades in the movie Star Trek II: The Wrath of Khan with the following words to Captain Kirk: "The needs of the many outweigh the needs of the few, or the one…"

Now, revealing new research shows that people with damage to a key emotion-processing region of the brain also make moral decisions based on the greater good of the community, unclouded by concerns over harming an individual.

It is the first study to demonstrate how emotion impacts moral judgement and sheds light on why people often act out of respect for an individual rather than choosing to act in a more logical, utilitarian way. The findings could cause a rethink in how society determines a "moral good", and challenge the 18^th-century philosophies of Immanuel Kant and David Hume.

Antonio Damasio at the University of Southern California in Los Angeles, US, and colleagues recruited 30 people for their experiment. Six of the subjects had suffered damage to a region in the front of the brain known as the ventromedial prefrontal cortex (VMPC), which regulates emotions. The participants had this brain injury as a result of an aneurism or tumour growth in the VMPC region.

Twelve participants in the study had damage to other parts of the brain but not the VMPC. And the remaining 12 subjects had no brain injury whatsoever.

"Utilitarian" action

The researchers presented participants with various scenarios (scroll to the bottom for several examples) and asked them to make decisions based on the information provided. Some of the situations involved moral decision-making. For example, subjects had to say whether they would throw a person in front of a train if doing so would stop the train from barrelling into five workmen, killing all five.

In such a situation, most people would find it morally unacceptable to push someone to his or her death – even if doing so would save the lives of others. And this was the reaction of the healthy participants or those that had injury to brain regions excluding the VMPC. But people with damage to the VMPC showed a willingness to take this type of "utilitarian" action.

"You have one group that is ready to endorse what we would regard as an overly utilitarian judgment and the other far less" willing to do so, explains Damasio. He notes that the patients with VMPC damage generally made the same decisions as their control counterparts when it came to non-moral scenarios.

Subtle scenarios

Notably, people with VMPC damage were just as likely as their counterparts to endorse "impersonal" moral decisions that involved indirectly putting strangers at risk for the greater good. These impersonal moral scenarios involved, for example, encouraging the use of a vaccine that would protect the public but cause an adverse reaction in a few individuals.

These results suggest that emotions play a crucial role in moral decisions involving personal contact – but not in moral judgments involving distant, indirect impacts on other people. "What's beautiful to me is how subtly different the situations are," says Marc Hauser at Harvard University in Cambridge, Massachusetts, US, one of the researchers involved.

The finding that some moral judgments involve emotions while others do not supports the supposedly diametrically opposed thinking of philosophers Immanuel Kant and David Hume.

"It means both Kant and Hume are right. Philosophers will have a fit because they like to choose sides," says Frans de Waal at Emory University in Atlanta, Georgia, US. Hume believed that people could be motivated to make proper moral decisions based on their sympathy for others. Kant, meanwhile, warned that moral judgments might be corrupted by emotions.

Personal dignity

Philip Kitcher, who teaches philosophy at Columbia University in New York, US, notes that the study of brain damaged individuals presents a unique challenge to Kant's philosophy. While Kant cautioned against the corruptive influence of emotions, he also argued that individuals have personal dignity, which must be respected.

Yet in the new study, subjects who had impaired emotion processing due to VPMC damage showed the least concern for individual dignity in the personal moral dilemmas that involved directly harming another person to save others. This provides strong biological evidence that emotions enable us to respect individual dignity, says Kitcher.

"Emotions are an anchor for our moral systems. If you remove that anchor you can end up anywhere," says de Waal.

Examples of scenarios used in the experiment:

Non-Moral Scenario: Investment Offer

You are at home one day when the mail arrives. You receive a letter from a reputable corporation that provides financial services. They have invited you to invest in a mutual fund, beginning with an initial investment of one thousand dollars.

As it happens, you are familiar with this particular mutual fund. It has not performed very well over the past few years, and, based on what you know, there is no reason to think that it will perform any better in the future.

Would you invest a thousand dollars in this mutual fund in order to make money?

Impersonal Moral Scenario: Standard Trolley

You are at the wheel of a runaway trolley quickly approaching a fork in the tracks. On the tracks extending to the left is a group of five railway workmen. On the tracks extending to the right is a single railway workman.

If you do nothing the trolley will proceed to the left, causing the deaths of the five workmen. The only way to avoid the deaths of these workmen is to hit a switch on your dashboard that will cause the trolley to proceed to the right, causing the death of the single workman.

Would you hit the switch in order to avoid the deaths of the five workmen?

Personal Moral Scenario: Submarine

You are the captain of a military submarine travelling underneath a large iceberg. An onboard explosion has caused you to lose most of your oxygen supply and has injured one of your crew who is quickly losing blood. The injured crew member is going to die from his wounds no matter what happens.

The remaining oxygen is not sufficient for the entire crew to make it to the surface. The only way to save the other crew members is to shoot dead the injured crew member so that there will be just enough oxygen for the rest of the crew to survive.

Would you kill the fatally injured crew member in order to save the lives of the remaining crew members?

Personal Moral Scenario: Infection

Someone you know has AIDS and plans to infect others, some of whom will die. Your only options are to let it happen or to kill the person.

Do you pull the trigger?

Journal reference: Nature (DOI: 10.1038/nature05631)

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Lisboa

Quinta, 22 de Março de 2007 Edição Papel Decisões morais falham se não houver emoção Filomena Naves É um cenário teórico extremo: alguém com uma doença infecciosa e mortal decide infectar propositadamente outras pessoas, muitas das quais morrerão, e a única hipótese de evitar que isso aconteça é matar essa pessoa. Confrontada com um dilema desta natureza, a maioria das pessoas hesita, ou diz que não o faria, mesmo pensando que em teoria devia fazê-lo. No entanto, doentes com uma lesão muito localizada no cérebro são um caso à parte. E a sua escolha num cenário deste tipo é apenas a escolha lógica, sem as emoções a desencadear hesitações. Conclusão: as emoções desempenham um papel causal importante nas nossas decisões morais. Este é o resultado da mais recente investigação sobre as emoções e o cérebro realizada por uma equipa de neurologistas norte-americanos co--liderada pelo neurocientista português António Damásio. Publicado hoje na Nature, este estudo é também o primeiro a demonstrar esta função das emoções. Sem elas, algumas decisões morais mantêm a lógica, mas resultam frias e inumanas. A lesão cerebral em causa localiza-se no cortex pré-frontal, numa zona chamada VMPC (ventromedial prefrontal cortex, em inglês), e para avaliar o seu papel nas decisões morais a equipa montou uma experiência em que participaram 30 pessoas, dividas em três grupos. Um com este tipo de lesão cerebral, outro com lesões noutras regiões do cérebro e outro ainda sem qualquer lesão cerebral. Todos os participantes foram sujeitos a um questionário com uma série de cenários que envolviam escolhas como a já referida. "A maioria das pessoas sem esta lesão específica fica dividida. Mas estes indivíduos [com lesão na VMPC] parecem não sentir o conflito", explicou António Damásio, que dirige o Brain and Creativity Institute na University of Southern California, em Los Angeles, nos EUA. "É incrível como esta lesão é selectiva", notou Marc Hauser, professor de psicologia em Harvard e co-autor do estudo, sublinhando que ela "interfere com a capacidade de decisão moral quando uma acção negativa entra em conflito com o resultado utilitário". Um sentimento de aversão impede os seres humanos de fazer mal uns aos outros. Com esta lesão cerebral, esse mecanismo deixa de existir.