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Guy Kahane

Disagreement about value or about the facts?

Both within and outside ethics, people often worry about disagreements that are purely about value. Suppose that you and I completely agree about all the empirical facts about some case, yet you think that it’s absolutely forbidden to do something and I think there is absolutely nothing wrong with it. It can seem hard to see how we could ever resolve our disagreement. If after I have carefully considered the case, and still see nothing wrong, what could you possibly say that would make me see things in a different light?


Things are often a bit more complicated than this. For example, even if we agree on all the empirical facts, our moral disagreement might be due to disagreement about some metaphysical matter—say, about whether a foetus is a person. Metaphysical disagreements are also extremely hard to resolve. Then there is the old point that the way we frame factual matters, or the way we interpret some empirical evidence, might itself be shaped by our values.


Anyway, this is a common worry. But when it comes to many heated disagreements about scientific or technological advances, this worry seems to me to get the situation exactly backwards.

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The Great Botox Experiment in Mood Enhancement

Suppose that the people around repeatedly smile or shake their heads. Although you may not notice it, it is very likely that soon you too will begin to smile or shake your heard. And it is likely that this will affect how you feel and what you think. Or at least this is what social psychology tells us.

In one experiment that demonstrated this ‘chameleon effect’, subjects were recorded unconsciously imitating the movements of an experimenter. In another experiment, when subjects contorted their faces in a way that paralleled smiling, they felt happier. And when subjects were told to engage in tasks that required them to move their heads as if they nodding or shaking it, this affected how easy it was to persuade them of something—it was easier to persuade them if they were nodding their head, harder if they were shaking it! (though only if the argument was good—see here for details.) What’s all this got to do with botox?

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Cognitive Science Advice for Republicans and Democrats?

The upcoming US elections have revived the culture wars but so far controversy about science and biotechnology has not taken centre stage, as both candidates support stem cell research. But science is still playing a minor role in the discussion. Writing in the New York Times, the influential conservative pundit David Brooks recently gave advice to his fellow Republicans. In recent years, he argues, they have come to endorse a rampant libertarian individualism and forgotten about the importance of social connections and bonds, once a core conservative value. This form of criticism is old and familiar. What is new is the form it now takes. What is wrong is wrong about the individualist outlook, Brooks argues, is that it is false to human nature, a fact apparently revealed by recent research in cognitive science, neuroscience, genetics, and behavioural economics, which has rediscovered the ‘old truth’—“that we are intensely social creatures, deeply interconnected with one another and the idea of the lone individual rationally and willfully steering his own life course is often an illusion.”

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The Stuff Dreams Are Made Of

Studies of the content of dreams confirm what most of us already suspect: dreams are more likely to be nasty than pleasant, or as the researchers put it, “negative dream contents are more frequent than corresponding positive dream contents”. A recent study reports that threatening experiences are more frequent and intense in dreams than in real life. All this is in line with the entertaining (and not implausible) ‘threat simulation theory’ of dreams, according to which the evolutionary function of dreams is to simulate threats so that our ancestors could spend their nights rehearsing attacks by enemies and predators.

So dreams have a serious negative bias. All of this might have been extremely useful back then. But an unwelcome consequence is that we spend a large portion of our life in pointless misery. Clinical depression is often understood as a disposition to obsessively accentuate the negative. It seems all of us are clinically depressed during certain hours of the night. Think of a human life and how many hours of sleep it contains. Of these, many are spent dreaming. And most of these dreams are unpleasant in different ways. If we add all this up, dreaming makes our lives significantly worse, on balance. Shouldn’t we do something about this?

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The Pregnant Man, And Other Conceptual Curiosities

Recent weeks have given us several occasions to reflect on the nature of parenthood. First we had the unavoidably salacious reports about the first pregnant man, Thomas Beatie—who turned out to be a woman who has had a sex change operation (in fact, the operation only involved the removal of breast glands to flatten her/his chest). Thomas Beatie’s wife Nancy apparently inseminated him using sperm from an anonymous donor—after first being refused medical assistance by eight different doctors. In an interview Beatie said, “It’s not a male or female desire to have a child,” he said. “It’s a human desire. I have a very stable male identity.” And Mrs Beatie explained that “He’s going to be the father and I’m going to be the mother,” she said.


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Peering into the mind and ‘new threats to privacy’

In recent studies, neuroscientists have been able to use brain imaging to reliably predict inner states such as lying or intention. In a groundbreaking study published in a recent issue of Nature (and briefly summarised here, here and here), Kay and his colleagues used functional magnetic resonance imaging (fMRI) to make predictions about what subjects were seeing. Using a complex mathematical model based on decades of research into the human visual cortex, measured brain activity to estimate which grayscale natural image the subject was seeing at a given point in time. This goes beyond prior attempts at ‘brain reading’ in that the analysis did not merely use simple artificial stimuli or generic statistical signal-processing methods to identify neural patterns but employed data about the early stages of visual processing to develop a model that was then able to accurately predict which of a large number of novel and complex natural images was seen by the subject.

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Restoring Sensation to Amputees’ Lost Limbs

Scientists at the Rehabilitation Institute of Chicago and Northwestern University made two amputees ‘feel’ their lost arms by rerouting to their chest the key nerves that transfer sensations from hand to brain. After several months, stimulation to the area of the nerves would produce rich sensations experienced as if occurring in the missing limbs. Interestingly, the patients could still distinguish between sensory stimulation of chest nerves and that of the rerouted arm nerves.

For a summary, see Yahoo News

For the original paper, see PNAS paper

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Imaging the Political Brain

In an interesting study published in the Journal of Cognitive Neuroscience in 2006 but widely circulated earlier, Drew Westen and his colleagues at Emory University used fMRI to image the brains of committed Democrats and Republicans before the 2004 Presidential election. Although the subject matter was topical, the aim of the study was not to… Read More »Imaging the Political Brain