the biology of humans in the best and worst. in it he writes about the biological origins of behavior and consciousness. he recently spoke at a bookstore in washington, d.c.. this is one hour. [applause] >> let me start off with a fantasy i've had that involves. i have managed to knock this out of his hand and the pill he keeps suicide rather than to be captured.

he comes at me in a rage that we wrestle and then say adolf hitler, i arrest you for crimes against humanity. what would i do if i had hitler in my hands and it isn't hard to imagine once i allow myself -- [inaudible] not hard to imagine once i all allow, take out his eyes with a blunt instrument, cut out his tongue, leave him alive on a respirator tube fed, not able to move, speak, here.

i had this fantasy since i was a kid and i still do sometimes and when i think about it, my heart beats faster except there is a problem except i don't believe in souls and evil and i think that it's only appropriate for. there was this one time i was in the laser tag place i had a good time hiding in the corner shooting people over and over until this kid is out to b got n times and snickered at me.

we have problems we have used showerheads to deliver poison gas, letters with anthrax, weapons in the military strategy, we are in miserably violent species. we don't hate violence we hate the wrong kind of violence because when it's the right kind we pay good money to watch it. when it's the right kind of violence we love it. but we are also an extraordinarily compassionate and altruistic one. so how do we make sense of this in our best and worst moments in all of those ambiguous ones in

between? it is boring to understand the biology of the aspects of your behavior. but. what is incredibly complicated as understanding the meaning of the behavior because it is an appalling act of another like self sacrifice and putting your hand on top of someone else's is deeply compassionate and a deep betrayal. that one is very challenging. one thing that is clear, you are never going to understand what's going on if you get it in your head that you will be able to explain everything when this is the part of the brain or the gene or the hormone or the childhood experience or evolutionary mechanism that

explains everything because it doesn't work that way. instead, any behavior that occurs is the outcome of the biology that occurred a second before an hour before. so to give you a sense of this okay, you are in a situation there is a crisis, violence going on, people running around, and there is a stranger running to you in an agitated state and you can't be sure for their thar facial expression is. maybe they are angry, they've got something in your hand that seems like a handgun as you are standing there and they come running at you and you shoot. then it turns out what they had in their hand was a cell phone instead. so we ask the biological question why did that behavior occur and it's a lot of

questions why did that behavior occur, what went on one second before that brought about the behavior? to begin to understand that come at the top of the brain that is a usual suspect is called the amygdala you want to think of aggression you think about the amygdala if you stimulate the amygdala in an experimental lab, you get an outburst of aggression and humans that have rare types of seizures that start. if you ask what the amygdala is about but isn't the first word that is going to come out of their mouth because for most people it's about fear and anxiety and learning to be

afraid without understanding the nano biology of fear and a world in which none need be afraid to be a lot more between lions and lambs. now the thing to begin to make sense of it is what part of the brain does it talk to. it does something very straightforward. you bite into a piece of food and it's spoiled. as a result the cortex activat

activates. it keeps them from eating poisonous foods and you do the same thing with human come and get a nice human volunteer who bites into the food. we do something fancier and all you do is think about eating something disgusting and the cortex activates but then something much more subtle have them tell you about a time that they did something miserable and brought into some other human or some other doing something miserable and brought into somebody else and the insular cortex will activate. every other mammal on earth is in disgust, but it also does moral disgust. what that tells you is something that is morally appalling we feel sick to our stomachs that

leaves a bad taste in your mouth. it's the symbolic thing of standards some 50,000 years ago and didn't invent a new part of the brain at the time and instead there was some sort of a big committee meeting and they said okay there's the insular disgust. the main part in talks to is the amygdala because once it decides that it's disgusting, you are a couple of steps away from it being scary and something you need to act against him.

at this distance would be harder to pick up a head of steam to be able to act against it. that's where the force comes to make a moral imperative imperative and that's great but the insular cortex isn't good at remembering. it's only a metaphor that you were feeling disgusted and suddenly, you have that whole problem of the world of people that were disgusted by somebody's behavior pitch in somebody else's eyes is just a normal and loving lifestyle and there is the danger to decide to be morally disgusted by

something is a good litmus test deciding between right and wrong and we sure know all the ways that can get you into trouble and probably most of all every ideologue in history has had a brilliant feeling. when you think of those that pray differently and love differently, the insular cortex activates because there's something disgusting about them. the key to every good genocidal movement is taking them and turning them into being such malignancies and whatever that they hardly even count as human anymore. so we've got this acces access d meanwhile the most interesting

part of the brain far and away the frontal cortex. it's kind of interesting and it's done well. we have more than any other species on earth and what does it do? the frontal cortex makes you do the harder thing when it's the right thing to do and impulse control and gratification postponement and long-term planning a consenting projections down to the amygdala helping to race there in time to save wait a second are you sure that is a handgun wait a second, i wouldn't do that if i were you

i know this seems like a brilliant idea right now but believe me you were going to regret it. now there's a picture of the frontal cortex and although it s is growth slowing down and in fact there is bidirectionality the amygdala has the means to talk to the frontal cortex. every time that we are in a moment of extreme aroused state and we make a decision that is hideously stupid and does * it seems brilliant at the time because that is the frontal cortex being marinated in what is down below in other words this is tempting to view for this computerlike part of the brain just marinating in its high directional communication.

making sense of this frontal cortex, the whole notion of giving the harder thing when it's the right thing to do is a value free judgment. sometimes you have to have an incredibly strong frontal cortex to resist the temptation to lie and that is the centerpiece of the crossroads in our lives. however, once you decide you are going to lie you need your frontal cortex to do it effectively. you will be tempted to twitch. keep your voice under control. it could take an enormous amount of discipline to go and effectively make the world hole in a better place but also an awful lot of discipline staying up late and studying to the ethnically cleansing villages the frontal cortex is value free in that sense. so we have this sense.

that's what is going on and one second before, but no brain is an island and now what we have to do is take a step back so what is going on in the second ten minutes before in the sensory environment which triggered that amygdala to do this or that are the stimuli that are coming in there now obviously in the scenario that we have com, the sights and sou. but you hardly even know that it's there and if you did not in a million years would you think it is pertinent for example when you have to make a split-second decision you are more likely to mistake a cell phone for a handgun as the person is holding it is male and of another race.

her brain processes that in 50 milliseconds her brain is already distinguishing that imperfectly. at the turnthat turns out to han interesting piece of the wiring. so suppose you look at somebody with something in her hand like a cell phone it goes from there i waystation of the brain and figures out the pixels are and then the second terms and you get a four dimensional picture that says i believe that is a handgun. this information comes in and shortcuts in other words they

know there is a handgun in the visual cortex with the pixels. that is good and helpful and to get the information quickly but it turns out you need all of those computational layers in your cortex to tell what they're accurately and in other words it gets very emotionally aroused before the conscious cortex and the accuracy is integrate. and thus if you are tired to come if you are hungry or in pain, if there is a bad smell around or anything that is happening, you are advising you towards mistaking a neutral facial expression for a threatening one, mistaking a cell phone for the handgun all in the seconds before. now we need to take a step further back. what about the hours to days before. how is that affecting how sensitive you are to the information that can we've moved

here to the realm of hormones and in that regard they are pertinent and stand out above all others. first the suspect it has to be pulled into this point which is testosterone. it's why every male culture and species on earth i under this pe acts. it causes come it doesn't cause aggression what it does is interpreting the information is being threatening and being provocative. take somebody and pump them up with testosterone and they decide to neutral facial expressions seen for a 20th of a second are threatening and suddenly it is all agitated and froth at the mouth.

it exacerbates the tendencies. it is just fine and what kind is not. testosterone doesn't make organisms more aggressive, what it does is makes more organisms likely to do whatever behavior is needed to hold onto the high status when it's being challenged. it's going to be a hold of aggression and that is the first. remarkably when you get high status by being generous and the offers thaoffers the unique and testosterone makes people more generous. the problem isn't that it causes aggression, the problem is we've rewarded with aggression.

if you took buddhist monks and shot them up with testosterone they would be running around doing random acts of kindness to see who could do the most and the most quickly. it's the values and rewards we play some aggression. meanwhile in the span of hours today, the other hormone that has just as deserved reputation in the opposite direction as this hormone oxytocin that is officially the grooviest hormone on earth because it causes bonding between mothers and infants and between monogamous couples and makes you more expressive and emotionally sensitive and more cooperative and charitable and more trusting and it is a whole new field called marrow marketing and they

are more likely to believe all sorts of gibberish and nonsense of people trying to sell you stuff whether it is their political viewpoint and if they can spray oxytocin like costco all over this country what that would do to the economy of like the nonsense. so it promotes social behavior until you look more closely and more recent work shows that is exactly what it does it makes you more cooperative and a generous and charitable and all of that people you categorize as being just like you and makes you more social towards in group members and when it comes to the out group members that makes people more zina sobek and more preemptively aggressive and less cooperative.

they gave everyone the standard philosophy to sacrifice one person and then there's the a we world of research on that. a third of the time a person would get a name peter or something like that. a third of the time or a remainder of the time they tend to have out of hostility. now you have this scenario do you push this in front of the

trolley, and what they show is give people the oxytocin and they are less likely to sacrifice whereas they can't read fast enough. it makes us nicer to people that are already predisposed that are being nice to and exaggerates the contrast. how about weeks to months before this into a narrow plasticity and the fact that the brain can change in response to experien experience. if you spend this time in trauma and stress from your image below will have grown larger. you will become sluggish and at that critical moment the amygdala is any more hysteric hyper reactive state.

they say are you sure if you pull the trigger you can see that changing but stepping back even further how about adolescence it's one second to whether or not you're going to pulyou were going topull the trl fact of this is it is going full blast full mature except for the frontal cortex until you've are about 25-years-old it's the last part of the brain to fully mature. it means adolescence and early adulthood at the time of life where environment and experience are sculpting your frontal cortex into the adult version

you were going to have enough one critical moment deciding what the outcome is and what it also tells you if if this is the last part of the brain to fully mature it is the part least shaped by genes and most shaped by environment. now stepping even further back how well it back to your childhood and life that is pertinent when the brain was being constructed. remember the experience in the period causes changes in the field of the other genetic changes that causes permanent changes in some genes and parts of the body and lifetime consequences and childhood matters this is one of those which childhood matters in a pertinent example of that is if you have spent your months being

just in higher levels of stress hormones from the circulation because mom is extremely stressed, as an adult thanks to the epigenetic changes during your life you your amygdala is going to be hyperactive and you are going to have higher levels of stress hormones which makes it even more reactive and makes the frontal cortex sluggish. ..

if you have one particular variant, you are very significantly more likely, as an adult, to commit antisocial violent. if and only if you were abused as a child. if you weren't, having that gene variant has serial increase on your risk factor. it's not your genes, it's way that genes interact with the environment. thus, starting with fetal life, the interactions between genes and environment are going to shape enormously what state your brain is in in that one critical second but do you pull the trigger or not. >> okay. but you've got to go even further back past you as a single organism, how about your ancestors. what were they up too. for example, if your ancestors were passed, people wonderin wandering deserts and grasslands, the odds are they would have been a culture of honor, high levels of

violence, clan vendettas, warrior, that's the whole world of if you come in take your camel and you do nothing about it, the next day they will come and take your entire heard in your wives and daughters too. clan violence going on for centuries and what is clear is if your ancestors were of a culture of honor centuries later, that still influences the values with which you were raised including how often mothers are holding their children. centuries worth of it. steps further back, where are the cultural differences coming from? from ecosystems, one example of that, you look at people living in deserts, and historically they are likely to come up with models theistic reasons. look at people in east asia who live in flat plain areas and they grow rice which requires collectivist farming

and you get a very collectivist mindset about cooperation. get people in the hill country's there and they grow wheat which is done in individual families and you get the same individualistic mindset that you get in people living in manhattan. it's all ecologically shaped. then we have to go even further back because you're talking about genes anywhere along the way and the evolution of the genes. what you wind up seeing is evolution has sculpted different primate species into having different characteristic levels of aggression. some primate species have virtually none and another extreme, immensely high levels and there's all sorts of biological traits that go along with the extremes and what about us, we are somewhere right in the middle between the two extremes. okay, in other words, if you want to understand why did this behavior occur, you have to take into account everything from one second before to a million years before. what you conclude from that?

it's capitated. okay, that's very useful. how about it's complicated and you better be real careful and cautious before you decide you understand the causes of the behavior, especially if it's behavior that you judge harshly because things can really go wrong with the wrong attributions and we have a very dark stained history of that occurring precisely those reasons. for me, when i look at all of this information, the single thing that i find to be most important has to do with change. every single biological fact i've given along the way is subject to change over time. ecosystems change. thousands of years ago the sahara was a lush grassland filled with hippos and giraffes. cultures change. in the 17th century, the scariest people in all of europe were the swedes who spent that whole century rampaging all over europe and

the swedes have not had a war in 203 years. they changed. most of all, brains change. circuits form. neurons wor weekend, patterns grow and brains expand and as a result, people change and they can change extraordinarily. some examples of it, change in people that can occur over the course of decades. a man who moves me enormously, a man by the name of john newton was a british theologian, he was a leading abolitionist and played a central role in the banning of slavery at the beginning of the 1800s in england. john newton spent the early decades of his adult life as the captain of the slave ship, and after he retired from that, he spent decades as a local person investing in the slave trade and growing rich from it until one day something changed in him. something changed, something

changed and he celebrated it to the thing he is most known for historically in a hymn that he wrote, amazing grace. another example, a man, who on the morning of december 6, 1941 was the lead pilot and one of the squadrons that took off from an air force base in japan and attacked pearl harbor. he was one of their star pilots, he led one of the divisions there and 50 years later, to the day, as an old man, he came toward a ceremony at pearl harbor commemorating it as an old man came forward in broken english and apologized to some of the elderly survivors on the ground and spent the rest of his life close with some of them. think about that transformation. if one of those men that he befriended had become a captive during world war ii, he might have happily walked into death. if he had been a captai

captive of one of those american men he might have taken his skull as a souvenir which was the standard thing done during world war ii with the japanese and instead, 50 years later he is writing a letter to that man's grandchildren, consoling them when grandpa has died. change can occur even faster over the course of hours, and the example just mesmerizes me was the first winter of world war i, the christmas of 1914. powers that be had worked out a truce that was supposed to go for a couple of hours and the idea was along the trenches of france, people would be able to come out and retrieve bodies from no man's land and go. them. they came out and retrieved the bodies and they helped each other carry the bodies.

they prayed together over the dead and shared christmas dinner and exchanged gifts. by the next day they were playing soccer together up and down no man's land and exchanging addresses to get together and see each other after the war was over. those truces went on for two or three days until the officers had to arrive and threatened to shoot them if they didn't go back to killing one another. it only took a few hours to go back to us versus them and all the people on the side of the trenches dying for no damn reason and being used as ponds. sometimes it can occur in seconds or minutes. historically, probably the single biggest for from the vietnam war was the massacre, a brigade of american soldiers went into an undefended village full of civilians and killed between 350 and 500 of

them, gang raped women and girls and mutilated bodies, utterly nightmarish because it occurred in the government covered it up as long as possible because ultimately they just slapped a few wrists and because it was not a singular incident, it was one of the nightmares of the vietnam war. that massacre was stopped by one man. a man named hugh thompson. he was piloting a helicopter gunship flying over the village and was seeing american soldier firing activity and thought they were under attack and got out and was reviewing the incomprehensible sight of american soldiers shooting elderly women, taking out babies from underneath the bodies of their mother and shooting them and figuring out what's happening and he got into his helicopter and in the course of minutes, undid every

bit of training he had had as to who is an us and who is a them. he took his helicopter, landed it between the last group of surviving villagers and american soldiers coming at them with their weapons, landed his helicopter and turned his machine guns on the american soldiers and said if you do not stop i will mow you all down. what is most important to me his none of these guys had fancier neurons than any of us. same neurotransmitters, same genes, same enzymes no fancier than any of us. what we are left with at the end is a version of that in evitable exasperating cliché, those who don't study history are destined to be able to repeat it. what we have here is the opposite. those who don't study the history of extraordinary human change and those who don't study the science of how we more readily go from the worst of our behaviors to the best ones are destined not to be able to repeat unbelievably magnificent moments like these.

let me stop at this point and, if there's any questions. [applause] okay. okay someone is coming to the microphone. >> so what's happening in the future of neurology that would give us hope for understanding the brain better and having better outcomes. >> okay. let me just take this book here, i haven't read this yet, but i skimmed it for the picture. here's one figure. i don't know if you can see on the left page, it's a whole bunch of graphs and the point is it's a bunch of graphs that

are doing like this and then suddenly they do that. what those are of a number of publications by year in various topics i talk about. for example, at the top one, 2002, 2006, 2010, the number of papers in the medical literature concerning the topic of oxytocin and trust. everything about it has been learned in the past ten years. here we have brain and aggression, 1985 there were essentially zero papers published. the last decade, more than 2000. every one of these, the vast majority of what we've learned has come in the past short amount of time. were only a couple hundred years into understanding that epilepsy is a neurological disease and not demonic possession. certain learning disabilities are due to malformations and it's not laziness or lack of

motivation for the vast majority of these factoids are ten or 20 years old and all that will happen is we will learn more and more of that stuff and what we are going to learn is to recognize the extent to which we are biological organisms and our behavior has to be evaluated in that realm. >> for my money, but that eventually does is make words like soul or evil utterly absurd but it also makes words like punishment or justice very questionable as well. i think it will require an enormous reshaping on how we think we deal with the most damaging human behaviors because none of it can be thought of outside the context of biology. >> you did mention the shard, the buddhist, but i had a sense that in my life i've been exposed to a number of techniques for creating people

that are like that, for example buddhist people, people who undergo psychoanalysis, or serious activities that come from the group relations that work or group therapy, there are tools that have that effect. what i'm wondering about is why those things are not customary. we don't have for example, they don't have a program to cause people in the community to meet together. there are packages that can do that, but it doesn't happen. why is that? >> the easy punchline is because they're usually really hard to do. one example that comes to

mind, okay, you've got conflicting groups that have meant for decades for millennia that have had us them dichotomies and for decades, this notion has been floating among around about contact theory which is that if you bring people from hostile opposing groups together and they get to know each other, they will recognize hey, were all the same and it will be wondrous and we will all be singing to buy our and it will be terrific and that's been the motivation for all sorts of these programs taking palestinian and israeli teenagers and putting them in summer camps, northern irish catholics, all of this, and list versions and what that extremely large literature has shown is that when it works right, it absolutely reduces group conflict and can cause lasting changes in perception where people can generalize beyond not just now i know one is really, but they can

generalize you into other groups and nonetheless, most of the ways wind up making things worse because it's very narrow domains where these things are. you have to get everybody on equal ground. they have to have shared goals and an absence of any symbols and if you have anything other than that, you will make things worse. in other words, none of these things are done easily, but they are all workable. >> you talked about the critical time of adolescence and the development of what we consider right and wrong. how do you address the generation that has been inundated with violence within their media and their videogames that they play and it sort of desensitizes them to ask of violence. >> okay, as a parent i am

absolutely horrified by all of that stuff and can easily go off to a rant on the consequences of it and i can find papers that are looking at video violence and the desensitizing effects, and if i really feel like going down to like the second subbasement and pullout journals from the 60s, there are the exact same papers were all you need to do is replace the word television with videogames. television, radio violence in the 1930s with detective stories, every single generation has wrestled with this. when you go through the massive literature, what you see is, on average, all of those forms of violence causes short-term burst and violent behaviors in individuals but in terms of weather has long-term consequences, in every realm you get a very familiar punchline, violent media makes aggressive individuals more aggressive. has no effect on anyone else because what it does is

legitimizes and habituate and inhibits individuals where we have a pre-disposition for it. in that regard, the good news is it's no worse than cop dramas sitting by the fireside traps in the 1930s. the bad effects are nonetheless, those who are vulnerable, this is a more vivid, more real form of imitating reality than anything that's been invented before. the general effects turn out not to be terribly malevolent. >> in your talk you point out how complicated it is to explain the behavior and the example you used is that you can put that person who was trying to figure out who handles a gun and they could be a police officer or anybody in that situation. a lot of neuroscience has been

brought into the courtroom. for that matter it's been brought into the classroom to to use a brain scan to explain something, but i wondered in particular, in the courtroom, where do you see that where people are bringing brain scans and it says my brain made me do it rather than me. >> great question. insanely contentious field. there are some very scary smart people that take the viewpoint that neuroscience is nowhere ready for prime time. just to give you a sense of where neuroscience plays a role in the american criminal justice system, the gold standard for deciding that someone who has committed a crime is so organically impaired that they can't be held responsible for their acts as if they basically cannot tell the difference between right and wrong. that is usually a way of describing extreme schizophrenic psychosis. this is something called the m'naghten rule was based on an

individual, a paranoid schizophrenic who was hearing voices and attempted to assassin the prime minister of england in 1840. that's the legal standard in the united states based on neuroscience from 1840. i mean, i don't think they had even evolved at that point. they have incorporated exactly zero neuroscience which is the realm of people who do know the difference between right and wrong, who nonetheless cannot regulate their behavior. where is that when you see damage to the frontal cortex? you get somebody there who can tell you absolutely which is the appropriate thing to switch, you can reach for five m&ms but you only get one as a reward and they say yes, i

know how it works and they go for the wrong one of the last incident. when you have frontal damage you know the difference between right and wrong and nonetheless, you cannot regulate your behavior. there is no state in this country that regularly excepts that impairment in criminal court. two horrifying statistics that are heard, 25% of men on death row in this country has a history of head trauma to the frontal cortex. other horrifying factoid, by the time you are five years old, the social economic status of your parents is a predictor of the levels of stress hormones in your bloodstream and what goes into the direction of the core and the more stress hormones, the bus frontal maturation. by kindergarten, if you were foolish enough to pic picked

the wrong family to have been born into, that is already going to impact your metabolism of your frontal cortex, the you are already three steps behind because of differences in this country. in that realm, consequences are enormous and hugely underappreciated. >> i'm a big fan. my question has to do with the role of testosterone and maybe some consequences of it and what we can do about it. if it's not related to aggression but it's related to an increase reward for status, where does it act in the brain? given that so many kids may suffer with impacts in the brain that might affect their aggression as adult, would a

pharmaceutical route that all suggested before any type of cognitive training because the industry will latch onto anything but i feel like that's something they haven't done but i don't feel like it's a long-term solution either. >> which part of the brain has the most receptors for testosterone and the most sensitivity to it? makes total sense. it's ground zero for sensitivity to testosterone. does it cause the neurons to fire, to in effect even invent aggressive output? not at all. if and only if they are already firing, testosterone makes them fire faster. they do not turn on the marshall music, it ups the volume if it's already been turned on. in terms of let's make the world a much better place, how about we get rid of all the males or let's castrate well

know, well, what about, okay, how about if we block some of the effects of testosterone and what you see there besides it being mighty scary is a track record of not working very well.

>> the is the first experiment ever done in endocrinology about 10000 years ago when bowls chase people around the backyard one time too many and they rustle them down and got rid of the testes and then he was more attractive all. if you castrate a male levels of aggression go down. they never go down to zero. the critical thing is, the more experience that mail had been aggressive prior to castration, the more is going to stay there afterward. in other words, the more experience you have with aggression, the less it is dependent on hormones on the more it is a function of social learning. so that is not much of a panacea there. final question. >> hopefully more optimistic we can end on a more optimistic note. you mentioned the chronic

stress. there are things that perhaps we could do for things with chronic stress. i'm thinking of people who have been on multiple tours over series another we have people do that more often there coming back and ending their lives. will be plenty meditation, maybe yoga, but, are there ways even with the example of testosterone and the role of -- of invoking aggression, are there ways we can reduce the size of the aggression? or of the amygdala? >> the realm that has been most studied is, trauma ptsd. you see and you get expansion of

the amygdala, it is overgeneralized into it being a terrifying world out there. my lab for a while was doing gene therapy work on trying to protect it from stress hormones in ways that us circus trip, is useful but now will help a mammal within the next century or so. my sense is that ptsd is not really anything that is ever cured. people learn how to manage and contain it. there is no clear, biological care. but something fascinating and horrifying has emerged in the literature in recent years. what is ptsd about? it's obvious it's fear, terror, trauma the people trying to kill you, of watching your buddy skilled ranji left and right. it is anchored in fear and the fear of the violence that may harm you and those whom you love. they've had to accommodate an extraordinary finding in recent years. which is, drone operators get

ptsd. they get ptsd at the same rate as to warriors in the battlefield. drone operators sitting there living in some supper of an f for space who get up in the morning and remember to drop off the clothing at the cleaners and get into traffic jams and barely make its work on top and then sit in the simulator for eight hours going to people on the other side of the planet. and then rush out at the end of the day to watch their little girl in a ballet concert. they go back to killing on the other side of the globe the next day. they had ptsd at the same age as soldiers. thus challenge the notion of what it's about. it's not the fact that there is nothing more abnormally terrifying to us in the notion of someone violently killing us, rather, is utterly bizarre and abnormal notion of us killing someone else. that's causing rethinking asked what ptsd is about. lurking in the is a little bit

of optimism. mandate david grossman who is a colonel in the u.s. military wrote an influential book on killing analyze the history of the extraordinary percentage of people throughout worse in the middle of battle with their lives are on the line at any given second who nonetheless never fired their guns. there is an enormous inhibition about doing that. at the battle of gettysburg there's 14000 rifles next to the dead in the field that were collected. the majority had not been fired. the majority have been loaded repeatedly, just about to shoot a better load, an enormous inhibitions against that. he argues that somewhere in the

is a greater spit of optimism, asking people to see kill some of faceless on the other side of the planet is easy. that someone to kill someone who's 10 feet away is historically -- there's some room for optimism there. the u.s. now trains more drone pilots and actual pilots. >> remember what i was saying before about castrated males or just hold her breath and try not to fall into too much despair. i spend my time on the college campus and i'm trying to console myself that this is going to generate new generation of activism if it produces ten times that the activism that the 60s did will still be an uphill battle to undo the battle that has been done. i don't have a lot of grounds of not being despairing in these times. you guys get to live here and watch the state by day. i get to live out lala land in

california and ignore when we want to. [applause] [inaudible] [inaudible] >> tonight a book tv, interviews with members of congress from our original series, afterwards.

senator sheldon whitehouse discusses his book, capture. about the political influence of corporations. then, senator ben sasse's book, but the vanishing american adult, about how to raise children to be independent. senator mike lee was about lesser-known funding father's in his book "written out of history". and it "the least among us" the work in defending antipoverty programs. book tv in prime time, here in c-span2. >> sending on q&a. >> the social and legal response to the issues that black men have is to lock us up, to poke at us in cages, to stop and frisk us, to treat us as citizens whose rates other people don't respect. we are not full citizens of the united states. >> paul butler takes a critical look at the criminal justice system and its impact on

african-american men in his book "chokehold". >> there's never been a time for community relations has been anywhere near good. so, for a long time if you're a black person and you call the police to report a crime, if you're the victim, the place to not pay that much attention to it. now, the senses that the police are overwhelmingly in african-american communities, but not to protect but rather to lock folks up. >> cognitive scientist is co-author of the book, the knowledge illusion about how communal intelligence and group think sheep are political opinions. talk about the book at the mit press bookstore in cambridge, massachusetts. this is under an