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340f05c
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Genes have plenty to do with behavior. Even more appropriately, all behavioral traits are affected to some degree by genetic variability.65 They have to be, given that they specify the structure of all the proteins pertinent to every neurotransmitter, hormone, receptor, etc. that there is. And they have plenty to do with individual differences in behavior, given the large percentage of genes that are polymorphic, coming in different flavors..
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Robert M. Sapolsky |
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bbe9dc5
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Work by Shelley Taylor of UCLA shows that "fight or flight" is the typical response to stress in males, and naturally, the stress literature is predominantly studies of males by males.83 Things often differ in females. Showing that she can match the good old boys when it comes to snappy sound bites, Taylor framed the female stress response as being more about "tend and befriend"--caring for your young and seeking social affiliation. This fi..
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Robert M. Sapolsky |
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7466b02
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What happens when children observe domestic violence, warfare, a gang murder, a school massacre? For weeks afterward there is impaired concentration and impulse control. Witnessing gun violence doubles a child's likelihood of serious violence within the succeeding two years. And adulthood brings the usual increased risks of depression, anxiety, and aggression. Consistent with that, violent criminals are more likely than nonviolent ones to h..
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Robert M. Sapolsky |
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39d5f47
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Why else evolve the fusiform? The shape of women's faces changes subtly during their ovulatory cycle, and men prefer female faces at the time of ovulation.
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Robert M. Sapolsky |
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35b6767
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As work continued, an important qualifier emerged. Low serotonin didn't predict premeditated, instrumental violence. It predicted impulsive aggression, as well as cognitive impulsivity (e.g., steep temporal discounting or trouble inhibiting a habitual response). Other studies linked low serotonin to impulsive suicide (independent of severity of the associated psychiatric illness).107
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Robert M. Sapolsky |
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59679c6
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Thus, for our purposes, genes aren't about inevitability. Instead they're about context-dependent tendencies, propensities, potentials, and vulnerabilities. All embedded in the fabric of the other factors, biological and otherwise, that fill these pages.
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Robert M. Sapolsky |
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3b63603
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Chapter 3 discusses some unsettling research--stick your average person in a brain scanner, and show him a picture of someone of another race for only a tenth of a second. This is too fast for him to be aware of what he saw. But thanks to that anatomical shortcut, the amygdala knows . . . and activates. In contrast, show the picture for a longer time. Again the amygdala activates, but then the cognitive dlPFC does as well, inhibiting the am..
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Robert M. Sapolsky |
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1df70ea
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increasing cognitive loadfn8 should make people more conservative. This is precisely the case. The time pressure of snap judgments is a version of increased cognitive load. Likewise, people become more conservative when tired, in pain or distracted with a cognitive task, or when blood alcohol levels rise.
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Robert M. Sapolsky |
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9bef3fe
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THE DELAYED MATURATION of the frontal cortex suggests an obvious scenario, namely that early in adolescence the frontal cortex has fewer neurons, dendritic branches, and synapses than in adulthood, and that levels increase into the midtwenties. Instead, levels decrease.
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Robert M. Sapolsky |
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c1e9566
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Fear, anxiety, the terror of mortality--it must be a drag being right-wing. But despite that, in a multinational study, rightists were happier than leftists.42 Why? Perhaps it's having simpler answers, unburdened by motivated correction. Or, as favored by the authors, because system justification allows conservatives to rationalize and be less discomfited by inequality. And as economic inequality rises, the happiness gap between the Right a..
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Robert M. Sapolsky |
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ddb9ecd
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We process emotionally salient information more rapidly and automatically, but with less accuracy. Frontal function--working memory, impulse control, executive decision making, risk assessment, and task shifting--is impaired, and the frontal cortex has less control over the amygdala. And we become less empathic and prosocial. Reducing sustained stress is a win-win for us and those stuck around us.
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Robert M. Sapolsky |
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0c6a436
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Over the course of minutes to hours, hormonal effects are predominantly contingent and facilitative. Hormones don't determine, command, cause, or invent behaviors. Instead they make us more sensitive to the social triggers of emotionally laden behaviors and exaggerate our preexisting tendencies in those domains.
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Robert M. Sapolsky |
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14f5b12
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testosterone increases the excitability of amygdaloid neurons, and glucocorticoids decrease excitability of prefrontal cortical neurons.
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Robert M. Sapolsky |
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4c1d353
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how acute stress strengthens connectivity between the frontal cortex and motoric areas, while weakening frontal-hippocampal connections; the result is decision making that is habitual, rather than incorporating new information. Similarly, chronic stress increases spine number in frontal-motor connections and decreases it in frontal-hippocampal ones.9
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Robert M. Sapolsky |
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8deb73a
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Second depressing finding: subliminal signaling of race also affects the fusiform face area, the cortical region that specializes in facial recognition.11 Damaging the fusiform, for example, selectively produces "face blindness" (aka prosopagnosia), an inability to recognize faces."
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Robert M. Sapolsky |
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a7c9cb9
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How does this work? Rodents produce pheromonal odors with individual signatures, derived from genes called the major histocompatibility complex (MHC). This is a super variable gene cluster that produces unique proteins that form a signature for an individual. This was first studied by immunologists. What does the immune system do? It differentiates between you and invaders--"self" and "nonself"--and attacks the latter. All your cells carry ..
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Robert M. Sapolsky |
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9e0de6c
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As we saw in chapter 9, it is only when groups get large enough that people regularly interact with strangers that cultures invent moralizing gods. These are not gods who sit around the banquet table laughing with detachment at the foibles of humans down below, or gods who punish humans for lousy sacrificial offerings. These are gods who punish humans for being rotten to other humans--in other words, the large religions invent gods who do t..
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Robert M. Sapolsky |
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8f82336
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I was in San Francisco for the quake, and much was made of the fact that fancy downtown hotels opened their doors to house people needing shelter. It's worth noting that this generosity was for people made homeless by the quake, not people who were already homeless. For them the earthquake was just another day of scrabbling. The hotels supposedly required a credit card from people, not because they'd be charged for the room, but as evidence..
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Robert M. Sapolsky |
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ba34c3c
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So ecological duress can increase or decrease aggression. This raises the key issue of what global warming will do to our best and worst behaviors. There will definitely be some upsides. Some regions will have longer growing seasons, increasing the food supply and reducing tensions. Some people will eschew conflict, being preoccupied with saving their homes from the encroaching ocean or growing pineapples in the Arctic. But amid squabbling ..
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Robert M. Sapolsky |
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fca9638
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In general, our morally tinged cultural institutions--religion, nationalism, ethnic pride, team spirit--bias us toward our best behaviors when we are single shepherds facing a potential tragedy of the commons. They make us less selfish in Me versus Us situations. But they send us hurtling toward our worst behaviors when confronting Thems and their different moralities.
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Robert M. Sapolsky |
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03568f2
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When facing Me-versus-Us moral dilemmas of resisting selfishness, our rapid intuitions are good, honed by evolutionary selection for cooperation in a sea of green-beard markers.35 And in such settings, regulating and formalizing the prosociality (i.e., moving it from the realm of intuition to that of cogitation) can even be counterproductive, a point emphasized by Samuel Bowles.* In contrast, when doing moral decision making during Us-versu..
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Robert M. Sapolsky |
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07c6556
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Finally, for the same criminal conviction, the more stereotypically African a black individual's facial features, the longer the sentence.15 In contrast, juries view black (but not white) male defendants more favorably if they're wearing big, clunky glasses; some defense attorneys even exploit this "nerd defense" by accessorizing their clients with fake glasses, and prosecuting attorneys ask whether those dorky glasses are real. In other wo..
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Robert M. Sapolsky |
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c37c858
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willpower takes metabolic power, thanks to the glucose demands of the frontal cortex. This was the finding that when people are hungry, they become less generous in economic games.
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Robert M. Sapolsky |
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3024f05
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In contrast, conservatives heavily value loyalty, authority, and sanctity. Obviously, this is a big difference. Is it okay to criticize your group to outsiders? Rightists: no, that's disloyal. Leftists: yes, if justified. Should you ever disobey a law? Rightists: no, that undermines authority. Leftists: of course, if it's a bad law. Is it okay to burn the flag? Rightists: never, it's sacred. Leftists: come on, it's a piece of cloth.
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Robert M. Sapolsky |
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4e873d0
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These differing emphases explain a lot--for example, the classical liberal view is that everyone has equal rights to happiness; rightists instead discount fairness in favor of expedient authority, generating the classical conservative view that some socioeconomic inequality is a tolerable price for things running smoothly.
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Robert M. Sapolsky |
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734c8ad
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When testosterone rises after a challenge, it doesn't prompt aggression. Instead it prompts whatever behaviors are needed to maintain status. This changes things tremendously... Engineer social circumstances right, and boosting testosterone levels during a challenge would make people compete like crazy to do the most random acts of kindness. In our world riddled with male violence, the problem isn't that testosterone can increase levels ..
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Robert M. Sapolsky |
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3b36de0
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The brain is heavily influenced by genes. But from birth through young adulthood, the part of the human brain that most defines us is less a product of the genes with which you started life than of what life has thrown at you. Because it is the last to mature, by definition the frontal cortex is the brain region least constrained by genes and most sculpted by experience. This must be so, to be the supremely complex social species that we ar..
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nature-vs-nurture
brain
genes
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Robert M. Sapolsky |
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17c7375
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What helps define a particular culture? Values, beliefs, attributions, ideologies.
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Robert M. Sapolsky |
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7f52283
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when women are ovulating, their fusiform face areas respond more to faces, with the ("emotional") vmPFCs responding more to men's faces in particular."
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Robert M. Sapolsky |
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ba57a6c
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US/THEM-ING TYPICALLY involves inflating the merits of Us concerning core values--we are more correct, wise, moral, and worthy when it comes to knowing what the gods want/running the economy/raising kids/fighting this war. Us-ness also involves inflating the merits of our arbitrary markers, and that can take some work--rationalizing why our food is tastier, our music more moving, our language more logical or poetic.
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Robert M. Sapolsky |
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0a23f8e
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when conservatives, but not liberals, are instructed to use reappraisal techniques (e.g., "Try to view the images in a detached, unemotional way"), they express less conservative political sentiments. In contrast, a suppression strategy ("Don't let your feelings show when you're looking at this image") doesn't work. As we saw, make a liberal tired, hungry, rushed, distracted, or disgusted, and they become more conservative. Make a conservat..
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Robert M. Sapolsky |
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52aa177
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Why has East Asia provided textbook examples of collectivism?21 The key is how culture is shaped by the way people traditionally made a living, which in turn is shaped by ecology. And in East Asia it's all about rice. Rice, which was domesticated there roughly ten thousand years ago, requires massive amounts of communal work. Not just backbreaking planting and harvesting, which are done in rotation because the entire village is needed to ha..
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Robert M. Sapolsky |
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e697fd3
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The United States was not without labor-intensive agriculture historically. But rather than solving that with collectivism, it solved it with slavery.
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Robert M. Sapolsky |
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67eb183
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Thus political orientation about social issues reflects sensitivity to visceral disgust and strategies for coping with such disgust.
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Robert M. Sapolsky |
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91ee9cb
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Southern violence was explored in one of the all-time coolest psychology studies, involving the use of a word rare in science journals, conducted by Nisbett and Cohen. Undergraduate male subjects had a blood sample taken. They then filled out a questionnaire about something and were then supposed to drop it off down the hall. It was in the narrow hallway, filled with file cabinets, that the experiment happened. Half the subjects traversed t..
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Robert M. Sapolsky |
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6986dae
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Dogs attempt to deceive one another, with marginal success--when a dog is terrified, fear pheromones emanate from his anal scent glands, and it's not great if the guy you're facing off against knows you're scared. A dog can't consciously choose to be deceptive by not synthesizing and secreting those pheromones. But he can try to squelch their dissemination by putting a lid on those glands, by putting his tail between his legs--"I'm not scar..
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Robert M. Sapolsky |
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03772fc
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Correlation and causality. Why is it that throughout the animal kingdom and in every human culture, males account for most aggression and violence? Well, what about testosterone and some related hormones, collectively called androgens, a term that unless otherwise noted, I will use simplistically as synonymous with testosterone. In nearly all species, males have more circulating testosterone than do females, who secrete small amounts of and..
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rape
violence
nature-versus-nurture
sex-offenders
sexual-assault
testosterone
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Robert M. Sapolsky |
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09be4c3
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It is the punisher's mind-set where everything must be changed. The difficulty of this is explored in the superb book The Punisher's Brain: The Evolution of Judge and Jury (2014) by Morris Hoffman, a practicing judge and legal scholar.31 He reviews the reasons for punishment: As we see from game theory studies, because punishment fosters cooperation. Because it is in the fabric of the evolution of sociality. And most important, because it c..
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Robert M. Sapolsky |
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9677424
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these capacities evolved so recently that our brains are, if you will, winging it and improvising on the fly when dealing with metaphor. As a result, we are actually pretty lousy at distinguishing between the metaphorical and literal, at remembering that "it's only a figure of speech"--with enormous consequences for our best and worst behaviors."
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Robert M. Sapolsky |
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792c64c
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Ask subjects to estimate the likelihood of the same events again. Adults incorporate the feedback into the new estimates. Adolescents update their estimates as adults do for good news, but feedback about bad news barely makes a dent. (Researcher: "How likely are you to have a car accident if you're driving while drunk?" Adolescent: "One chance in a gazillion." Researcher: "Actually, the risk is about 50 percent; what do you think your own c..
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Robert M. Sapolsky |
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1460313
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In a test of the theory, Kees Keizer of the University of Groningen in the Netherlands asked whether cues of one type of norm violation made people prone to violating other norms.39 When bicycles were chained to a fence (despite a sign forbidding it), people were more likely to take a shortcut through a gap in the fence (despite a sign forbidding it); people littered more when walls were graffitied; people were more likely to steal a five-e..
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Robert M. Sapolsky |
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2cc9071
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I can't really imagine how to live your life as if there is no free will. It may never be possible to view ourselves as the sum of our biology. Perhaps we'll have to settle for making sure our homuncular myths are benign, and save the heavy lifting of truly thinking rationally for where it matters--when we judge others harshly.
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Robert M. Sapolsky |
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e391385
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It is far from guaranteed that an empathic state leads to a compassionate act. One reason for this is captured superbly by the essayist Leslie Jamison: [Empathy] can also offer a dangerous sense of completion: that something has been done because something has been felt. It is tempting to think that feeling someone's pain is necessarily virtuous in its own right. The peril of empathy isn't simply that it can make us feel bad, but that it ca..
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Robert M. Sapolsky |
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2d0e135
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If their heart rate increases a lot (a peripheral indicator of anxious, amygdaloid arousal), they are unlikely to act prosocially in the situation. The prosocial ones are those whose heart rates decrease; they can hear the sound of someone else's need instead of the distressed pounding in their own chests.fn9,48
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Robert M. Sapolsky |