My thesis with regard to sex differences is quite moderate, in that I do not discount environmental factors; I'm just saying, don't forget about biology. To me that sounds very moderate. But for some people in the field of gender studies, even that is too extreme. They want it to be all environment and no biology. You can understand that politically that was an important position in the 1960s, in an effort to try to change society. But is it a true description, scientifically, of what goes on? It's time to distinguish politics and science, and just look at the evidence.
ASSORTATIVE MATING THEORY [4.6.05]
THE REALITY CLUB: Marc D. Hauser, Steven Pinker, Armand Leroi, Carole Hooven, Elizabeth Spelke, Alison Gopnik, David C. Geary, Helena Cronin, Linda S. Gottfredson. NEW Baron-Cohen responds.
"My new theory is that it's not just a genetic condition," he says, "but it might be the result of two particular types of parents, who are both contributing genes. This might be controversially received. This is because there are a number of different theories out there — one of which is an environmental theory, such as autism being caused by vaccine damage — the MMR vaccine (the measles, mumps, and rubella combination vaccine). Another environmental theory is that autism is due to toxic levels of mercury building up in the child's brain. But the genetic theory has a lot of evidence, and what we are now testing is that if two "systemizers" have a child, this will increase the risk of the child having autism. That's it in a nutshell.
realizes that his theory might raise anxieties. "Just
potentially controversial," he says, "doesn't
we shouldn't investigate it. And there are ways that you can
investigate it empirically."
SIMON BARON-COHEN is Professor of Developmental Psychopathology and Director of the Autism Research Centre at Cambridge University. He is also a Fellow of Trinity College, Cambridge. His books include Mindblindness; and The Essential Difference: The Truth about the Male and Female Brain.
ASSORTATIVE MATING THEORY
Recent work on imprinted genes a class that fails to follow the classic Mendelian patterns of inheritance shows that maternal contributions are often in complete conflict with paternal contributions. For example, with some imprinted genes, the maternal copy is quiet and the paternal copy is expressed, causing the fetus to extract more from its mother than she would like; these genes often cause pregnancy complications such as gestational diabetes. Studies of the brain using neuroimaging reveal sex differences in structure and function, and work with patient populations reveal differences in vulnerability to mental disorder. And closer to home, there are massive sex differences in the incidence of autism, with studies reporting an 8:1 bias in favor of males.
Where the debate gets interesting is when one attempts to explain how tightly the biology constrains our thoughts, preferences and actions. Baron-Cohen's assortative mating hypothesis is an attempt to grapple with this issue. Much of the evidence hinges on the early appearance of sex-specific signatures of mental function. Early signatures are a tell-tale sign of an innate capacity peaking through, but they are not definitive. One needs to rule out that the experience obtained is insufficient for a learning mechanism to create the capacity.
And here is where Baron-Cohen's observation that newborn boys like to look at mobiles and little girls at faces is fantastic, and just the right kind of start into a serious research program on the biology of sex differences; these results fit nicely with other data showing that for spontaneously generated paintings by young children, little girls almost always draw one or more people into the scene, whereas little boys rarely do, using their canvas as a vehicle for vehicles, from rocket ships to more mundane cars and bicycles.
But now comes the hard work.
What is it about the male genome that sets up a preference for the mechanical or physical whereas the girl genome leans toward faces and the social? How quickly, and with what kind of experience, can these initial biases be exaggerated? Why did these differences evolve? In the language of Darwin, what selected for this kind of preference? Was it our division of labor, with males focused on hunting and therefore technology, while females focused on gathering and the schmoozing that goes on during this kind of activity?
One clue that these are evolved sex differences comes from recent work looking at the incidence of innovation among primates. Across all the primates, including our closest relatives the chimpanzees, males are far more likely than females to take the lead in innovation, and much of the creativity lands in the domain of tool technology. In contrast, for most primate societies, females are for more engaged in the intricacies of social life than are males, largely because females tend to stay in their natal groups for life whereas males emigrate out. If there is a bias toward male folk physics and female folk psychology, there may be traces way back to our primate ancestors.
How are data like Baron-Cohen's reconciled with the fact that for imprinted genes, maternally active copies appear to be largely expressed in the rational frontal lobes whereas the paternally active copies appear to be largely expressed in the emotional limbic lobes? Are there in utero battles that arise over the concentration of testosterone circulating during development, with paternally active genes pushing hard for increased testosterone to push growth and toughness? Are maternal copies pushing in a different direction, attempting to regulate the physiology in such a way that their offspring are social specialists?
What makes work like this so very difficult, especially in terms of selling it to the public, is that more often than we would like to admit, reported sex differences either crumble in the face of follow up work, or for those differences that have been reported and replicated, claims regarding biological underpinnings have fallen prey to more experientially-based accounts. One only need think back to gay genes and gay brains, and the sad fate of those results. Thus, although I am sympathetic to Baron-Cohen's research project and find it odd that anyone would consider this work controversial, there is an obligation to get the story right here that far exceeds the demands in other areas.
Baron-Cohen wonders why sex is so often referred to these days as "gender." Part of it is a new prissiness — many people today are as squeamish about sexual dimorphism as the Victorians were about sex. But part of it is a limitation of the English language. The word "sex" refers ambiguously to copulation and to sexual dimorphism, and it's often important not to confuse them! The linguistic term "gender" literally means "kind," as in the cognates "genus," "generic," and "genre." Languages often subdivide their nouns into kinds for purposes of inflection, such as human/nonhuman, animate/inanimate, long/flat/round, vowel-final/consonant-final, and male/female. Many Indo-European languages have a gender distinction in their nouns that aligns with a masculine/feminine distinction in their pronouns, and so "gender" was pressed into service as a way to refer to the difference between men and women. Some academics want "gender" to refer specifically to socially defined rather than biologically determined patterns of sex-typical behavior, but this guideline, like most top-down prescriptions about lexical semantics, is rarely obeyed. The basic problem is that we have three concepts to convey — intercourse, dimorphism, and social roles — and at best two words with which to convey them.
I was amused to read that "It may be simply that the climate has now changed, and that people are much willing to accept that there are sex differences in the mind, and that these might even be partly biological." Was this interview conducted before the event that is coming to be known as "1/14"?
[ED. NOTE: The interview took place at Trinity College on 3/12.]
I am not, however, wholly convinced by his argument that autistic children — nearly always boys — are, in effect, hypermales. Baron-Cohen has shown that, relative to girls, boys are good at systematising and poor at empathising, and that autistic boys are exceptionally so. This fascinating result then raises a question, namely, why should these two, seemingly unrelated, attributes should trade-off with each other?
answer seems to
be: foetal testosterone.
boys were exposed
to unusually high
levels of testosterone
in the womb, so
of their brains,
part. It's an exaggeration
of a normal process.
This strikes me
as perfectly plausible,
but it also entails
a number of peculiar,
if testable, consequences.
Psychologist, University of Missouri; Author, Male, Female.
Baron-Cohen's proposals regarding the potential origin of autism and the relation to sex differences in cognition are very interesting and provocative, and at the very least will spur the field to think about these issues in different ways.
I wonder though if 'systematizer' is really the best way to conceptualize the autistic mind in particular and the male mind in general. Systematizing and searching for within category laws suggests explicit, conscious mechanisms that can be focused on more narrow domains, such as knowledge of biology or engineering. There is no doubt that humans are good at this sort of cognitive activity, and there may be more males than females who obsessively engage in systematizing. But in general, there do not appear to be large sex differences in the ability to consciously represent information in working memory and to organize this information in meaningful ways (this is another ways of saying there aren't large differences in general fluid intelligence). Still, boys and men do focus on different aspects of their world than do girls and women and work to organize their worlds in different ways.
More precisely, there are sex differences in more fundamental and implicit cognitive systems that may better capture the male mind and perhaps the mind of many individuals with autism than systematizer. Most broadly, these implicit systems encompass the domains of folk psychology (e.g., theory of mind, face processing), folk biology (e.g., categorizing flora and fauna in the local ecology), and folk physics (e.g., navigation, cognitions but tool use). Each of these folk domains is composed of a number of more specialized systems that in total seem to capture the essence of the evolved human mind.
Girls and women typically outperform boys and men in folk psychological domains — they are better at reading facial expressions, gestures, and at language production, among other differences - and boys and men typically outperform girls and women in folk physical domains — they are better at most spatial tasks, navigating in novel environments, and have a better intuitive grasp of tools. The book is open regarding sex differences in folk biological domains, although I suspect a male advantage in some subareas and a female advantage in others.
In any case, some of the patterns described by Baron-Cohen here and elsewhere (e.g., the results for visualization, over-representation of the relatives of autistic individuals in engineering) suggest that the autistic mind — and that of males — may be better described as being biased toward folk physics, at a cost to folk psychological systems.
Finally, I'd like to point out that many sex differences in general can be conceptualized in terms of Darwin's sexual selection, that is, competition with members of one's own sex for access to desired mates, and mate choice. The advantage of girls and women in many folk psychological domains can be understood in terms of female-female competition over boyfriends, would-be husbands, and other resources. Girls and women compete by gathering as much information on other people as they can get and then using this information to attempt to organize their web of social relationships so as to have better control of these relationships and through this access to what they want. This is called relational aggression. This way of 'fighting' will elaborate folk psychological brain and cognitive systems and eventually result in a sex difference in the same way that male-male physical contests over mates will result in the evolution of bigger and stronger males. Male-male competition may have favored an elaboration of folk physical domains in boys and men, because these support common survival — and reproduction-related activities of men in traditional societies and presumably during human evolution (e.g., navigation in novel terrain to hunt or engage in raiding parties). These types of evolutionary mechanisms provide a very useful big picture framework for hormonal studies that focus on proximate mechanisms.
Baron-Cohen's view is that psychological sex differences in our species can be characterized as male minds tending more towards systemizing than empathizing, female minds vice versa.
The Darwinian understanding of sex differences is that they arise from a trade-off between two kinds of reproductive investment: competing for mates and caring for offspring. Systematic sex differences in investment have been the rule almost since the dawn of high-tech sexual reproduction about 800 million years ago. This is because sexual reproduction of that kind began with one sex specializing slightly more in competing and the other slightly more in caring; that divergence then rapidly became self-reinforcing; and so it widened over evolutionary time, with the differences proliferating and amplifying, down the generations, in every sexually reproducing species that has ever existed. Thus it is that, throughout the living world, males and females tend to differ in much the same characteristic ways. By and large, males are competitive, promiscuous, risk-taking, status-seeking, tenacious, flamboyant; females are less so, for all of the above.
How does Baron-Cohen's view of sexual dimorphism in our species fit within this larger framework? The task of integrating his perspective has not yet been tackled. But this unfinished business is clearly important; and the result could benefit Simon's thesis in several ways. Consider, for example, questions to do with adaptation.
The Darwinian view of sex differences is adaptationist; it explains the differences as resulting from the very different adaptive problems that males and females faced because of their very different reproductive strategies. This raises the question: Are systemizing and empathizing also adaptations? And, if they are, what adaptive problems did they solve and how did they solve them? Alternatively, if they are not adaptations, which adaptations are they the products of? And how accurately do the categories 'systemizing' and 'empathizing' capture a relevant division in these underlying adaptations?
Thus, if Baron-Cohen's categorization reflects adaptive categories — either because it pinpoints specific adaptations or because it maps accurately onto underlying ones — then it can be slotted into its proper place in our wider understanding of psychological sex differences in humans. And we could then assess the robustness and scope of his theory — how reliably and how comprehensively systemizing-versus-empathizing characterizes the entire spectrum of differences.
So, embedding the distinction between systemizing and empathizing within that wider understanding could transform what might otherwise appear to be a merely pragmatic, even arbitrary, distinction into a rich explanatory and predictive theory.
And that would open up exciting new vistas. So, for example, it could shed light on male-female differences in other species. Are there any other species whose ancestors also faced adaptive problems to which systemizing and empathizing are a solution? And if this sex difference is peculiar to our species, why?
For all these reasons and more, I look forward to seeing Baron-Cohen's intriguing insights integrated into our understanding of sexual dimorphism in general.
By the way, moving from the science to its uses... Discussing the claim that sex differences are "all environment and no biology", Baron-Cohen says that one can appreciate "that politically that was an important position in the 1960s, in an effort to try to change society". But no; one most certainly should not appreciate it. If you really want to change society, you need first to understand it. An a priori commitment to 'environment over biology' sounds more like ideological posturing than a serious attempt to solve society's problems.
in vocational interest measurement, personality assessment, personnel
testing, and differential psychology have spent a century parsing,
cataloguing, and correlating these differences among individuals.
They find a regular pattern of sex differences regardless of age,
time, or place. It is not clear where Baron-Cohen's systematizer-empathizer
distinction fits in this much-explored territory, but it would seem
to map best onto dimensions in the non-cognitive realm: sympathetic
vs. cold ("agreeableness" personality dimension), "realistic" vs.
"social" vocational interests, or valuing "ideas" vs. "feeling."
NEW Baron-Cohen responds to Marc D. Hauser, Steven Pinker, Armand Leroi, Carole Hooven, Elizabeth Spelke, Alison Gopnik, David C. Geary, Helena Cronin, Linda S. Gottfredson on sex differences, linguistic ambiguity, systemizers, empathizers, politics in science, and the assortative mating theory
Marc Hauser raises some deep questions about how one can disentangle a genetic (particularly imprinted genetic) theory from an endocrine (particularly fetal androgen) theory of psychological sex differences. Of course, it needn't be the case that these two theories are in competition with each other. There may be both fetal androgenic effects (after the surge in testosterone produced by the testes in the male fetus at about 12-16 weeks gestation) and genetic effects that predate the production of androgens. Certainly in the animal literature there is evidence of both kinds of effects on sexual dimorphism in the brain and behaviour. It remains a challenge to conduct the right sorts of experiments that go to to the heart of which biological mechanisms underlie the observed sex differences in behaviour from birth.
refreshing that Hauser reacts with an open mind. He effectively says:
Suppose it were the case that the two sexes differ in the mind from
birth: how can we take such an idea to the next level of depth and
complexity? How can we isolate the possible biological and environmental
causes of such sex differences?
Pinker is on to something here, in that we are just emerging from decades of linguistic ambiguity and linguistic inadequacy. I would go one step further and argue that we probably have at least 7 different meanings, and only 2 words available to us. So, when we think about someone's sex, we can think about their chromosomal sex (how many X or Y chromosomes they have); their gonadal sex (do they have testes or ovaries); the sex of their brain (do they have the brain structure and function that is typical for people with their chromosomal sex); their sex-typical cognition (do they have the profile of strengths and weaknesses that is typical for people with their chromosomal sex); their sex-typical behaviour (do they act in ways that are typical for people with their chromosomal sex); their gender identity (do they identify with others who share their chromosomal sex); and finally, their sexual orientation.
The scientific studies that have been conducted are now beginning to show that whilst some of these 7 ways to think about sex may be linked. For example, if you have a Y chromosome then you are likely to develop testes, which in turn produce fetal testosterone which affected brain structure and function, cognition and behaviour. But some of these 7 ways to think about sex may be independent. For example, a girl with the genetic condition of congenital adrenal hyperplasia (CAH), which leads to over-production of fetal testosterone, is more likely to resemble a typical boy in her behaviour. Clearly we are going to need finer distinctions in our language to talk about someone's sex at all these different levels (and more), but it is interesting that even given the poverty of our vocabulary, this is not holding the science back. Key experiments (such as those with girls with CAH), are teaching us how to think about sex.
Armand Leroi wonders if children with autism are necessarily hyper-males. In particular, he asks, if this hypermasculinization is correct, why we don't see characteristics such as excessive aggression? I think Armand is right that some predictions flow from the theory. For example, do women with autism have delays in menarche, or have more male-typical interests? Experiments to look at these outcomes are underway in our lab. We should be careful though not to assume that all male characteristics are under the control of fetal rather than post-natal testosterone. Aggression for example may not be, whilst language development may be. We will need to differentiate the 'organizational' effects that testosterone may have during brain development from the 'activational' effects it may have at later points in development.
And we will need to keep in mind that if autism involves elevated levels of fetal testosterone, these may not be at the extreme levels as to cause clear changes to the sex organs, as in the female spotted hyena. Rather, these may simply be subtly higher levels that may affect brain and cognitive development. The effects may be subtle too, such as slowing language or social development. But these are empirical questions that I for one regard as important laboratory work to be undertaken.
Carol Hooven's comments are exactly on target. She raises the question: why do boys with CAH not have superior abilities in spatial tasks, if it is simply a function of how much fetal testosterone they produce? But the work of Grimshaw in Canada suggests that the relationship between fetal testosterone and spatial ability such as performance on the Mental Rotation Task is not linear; it may be an inverse U shape. Optimal performance may be in the low average male range, with either too much or too little fetal testosterone being correlated with worse performance. To me, this makes the mechanism all the more intriguing. I agree with her that we need more research into these delicate dose-dependent effects. Whether mating effort (the behaviour she has studied) has anything to do with fetal rather than current testosterone is an empirical question.
Elizabeth Spelke talks of 'systematizers' where I prefer the economy of syllables ('systemizers')! More seriously, she assumes I am discussing binary categories: either you're an empathizer or a systemizer. Nothing could be further from the claims in my theory. For me, these are continuous dimensions, not categories. For this reason, we developed metrics like the Empathy Quotient (EQ), or the Systemizing Quotient (SQ). It turns out that there are statistically significant sex differences on both of these measures. In my theory, I argue that it is the difference score that defines a typical male or female profile. It is not that female = empathizer (E) or male = systemizer (S). The claim is rather subtler than that. Rather it is that among females we find more individuals with a difference score such that E > S, and that among males we find more individuals with a difference score such that S > E.
Spelke also seems to have a concern that a single concept like systemizing can capture why individuals end up in such diverse occupations as cathedral building, ballroom dancing, or seal hunting. Interestingly, all 3 may be very good examples of systemizing, because they all involve understanding lawful or rule-based systems.
Spelke considers the newborn baby study that is currently a key piece of evidence for a stronger social interest in females and a stronger interest in objects among males. She worries that the experiment betrays something of my politics, but of course she knows nothing about my politics. If she assumes that because I tested sex differences at birth I must have conservative political leanings, or be against the equality of the sexes, she will have to take it on trust that the opposite is true. But more importantly, it is irrelevant. Hence my plea to keep politics and science clearly distinct, so that we can explore if and how and why the sexes are different, even if we are feminists or democrats.
I respect her for focusing on the experimental method of the newborn baby study. We want to know which methodological variables may have produced these results. She is right that all we know from this experiment is that more boys than girls looked for longer at the mechanical mobile, and more girls than boys looked for longer at the human face. But does this mean girls have a stronger interest in people than things, and boys have the opposite pattern of interests?
Possibly, but not necessarily. The infants' attention was being lured by two very moving objects. It could be that on average, more girls were attracted by the type of motion that faces have and, on average, more boys were attracted by the type of motion that mobiles show. Of course, re-describing the results in terms of motion-types may still be very important. For example, faces have 'biological' motion (they are self-propelled, with animacy) whilst mobiles have 'mechanical' or physical-causal motion. Are male and female brains on average tuned to react to these two types of motions differently? Further experiments would be needed to isolate if motion-type is the critical variable. In a first study we could not run additional controls to explore such possibilities, as babies will not tolerate a long experiment where such parameters can be varied systematically. But such additional experiments do need to be tried.
She worries if the experimenter was blind to the hypothesis being tested, or if the results could simply reflect experimenter-bias. I am glad I can reassure her on this point. The experimenters (there were two of them) asked mothers not to reveal the sex of their baby until after the experiment, precisely to avoid such experimenter bias. In 101 babies, there were I recall only 3 cases where the experimenter may not have been fully blind. The results were analysed with and without these 3 cases, and this did not change the pattern of results. More importantly, all that was filmed of each infant was the eye region of their face, so that later an independent panel of judges could look at each video film to measure the infants' looking time to each object. So the opportunity for experimenter-bias at the stage of coding the videos was zero. The experimenters were not the judges, and it was impossible for the judges to tell the sex of the baby from the eye-region of the face alone.
Since for some people, results of such experiments will be controversial, it is of paramount importance to control for such biases, which we took all possible human steps to do. Readers interested in the methodology can find the original article published in the journal Infant Behaviour and Development, to see how we attempted to put in place as many such controls as possible.
Spelke calls this a 'single' experiment, tested with a 'single' person and a 'single' object. If the implication is that following this novel experiment there is not yet a series of independent replication studies, then I agree that we must wait for these to be conducted. It is not that there is a set of failures to replicate. There are simply no attempts yet to replicate. I should point out that in terms of data collection, one is looking at perhaps 3-6 months of testing on a daily basis to complete a sample of about 100 babies, and I hope that other labs undertake this kind of research effort.
If the implication is whether the same results would be obtained with a different person, or a different object, these are good empirical questions. We ascertained that even testing newborns with one object compared to one person was an achievement, given a neonate's attention span. But I look forward to other scientists taking up the challenge of conducting different kinds of experimental manipulations with this age-group, so that we can start to examine issues of reliability and specificity of the results.
Spelke suggests that in 3 decades of infancy research, sex differences have not been observed. One has to remember that subtle sex differences if they exist are not going to emerge from small samples. A typical research project includes 20 babies, 10 of each sex, and researchers wisely do not test for sex differences when the power to detect such differences is not sufficient in such small samples. To demonstrate if a 3 month old infant understands a principle of folk physics, one does not need to test a sample of 100 babies. 20 may be enough. But to test for subtle sex differences, one just might need 100 (50 males and 50 females) in a single study.
And besides, it is not true that infancy studies have not reported significant sex differences. The MacArthur infant vocabulary scales report different norms for boys and girls at age 12 months precisely because girls vocabularies are bigger than boys from that age, and remain bigger over the next 24 months. Many independent studies show that girls on average also make more eye contact, and play with different kinds of toys to boys, from as early as 12 months old. What makes the neonatal study of sex differences new is the age at which they were tested.
Finally, Spelke concludes that "infants don't choose whether to systemize or empathize; they do both, and so do we". That's correct. We all do both. It is only a straw man who might be thought to argue that infants choose one or the other. Recall that we are interested in subtle discrepancies in the amount of a person's attention to the physical and social environment. Whilst in this experiment we may have categorized infants according to whether they looked longer at the face or longer at the mobile, we were still measuring differences in looking times at the two types of stimuli. No one is going to suppose for a moment that an infant is solely interested in one of these objects and not at all interested in the other. The world is not that black and white.
Alison Gopnik asks why on the false belief test, a test of 'theory of mind', no obvious sex differences have emerged. My answer to her excellent question is that 'theory of mind', and the false belief test in particular, is designed as a pass-fail kind of test. To pick up subtle individual differences you need a test with a fine-grained scale. To test for differences in height between the sexes you need a ruler with a resolution of centimeters. You can't just have a test such as 'can both sexes see over the table?' To test for a difference in head circumference between the sexes you need a ruler with a resolution of millimeters. Not just a test like 'can both sexes get the hat on their head?'
But there is another reason why theory of mind might not be the right place to look for sex differences, and that is because theory of mind is not the same as empathy. To empathize, you may need a theory of mind (to attribute or compute a person's mental states) but to empathize you have to do a lot more than simply attribute or compute a person's mental states. Psychopaths can attribute mental states but they don't have great empathy. And on tests of empathy, many studies find strongly significant sex differences.
David Geary proposes that sex differences in folk physics and folk biology may not equate with sex differences in systemizing. Why not? When we engage in folk physics or folk biology, surely we are trying to predict the behaviour of a system (a mechanical system, or a taxonomic system, or a digestive system, etc) in terms of its rules? That is systemizing. The concept of systemizing grew out of the older concept of folk physics, but I found the latter too restrictive because there are systems that are abstract (such as mathematics and music) that are as lawful as tools and machines, but are not well encompassed by the concept of folk physics.
Helena Cronin is of course right that we need to understand sexual dimorphism in a Darwinian framework, and she has done more than most academics to explore this framework for understanding human behaviour. The tough part of course is to test predictions from a Darwinian framework in a contemporary human population, when the relevant selection pressures may be ancient. But there are impressive examples of how this can be done.
Linda Gottfredson is the commentator who takes seriously the new idea about assortative mating of two strong systemizers as a cause of autism. Whilst this idea remains speculative, it is testable, and I am glad she pointed out that mating patterns in one generation can change rates of different characteristics in offspring in the next generation(s) with remarkable speed, and that mating patterns effectively create different environments that can affect child development.
I look forward to seeing the tests of the assortative mating theory of autism in the coming years. And I thank those who provided commentaries for their stimulating debate.
new essays by 27 leading Edge contributors..."Good,
narrative history, combined with much fine writing...quirky,
absorbing and persuasive in just the way that good stories
of the biggest brains in the world turn their lenses on their
own lives...fascinating...an invigorating debate."—Washington
Post "Compelling."—Discover " An
engrossing treat of a book...crammed with hugely enjoyable
anecdotes ...you'll have a wonderful time reading these reminiscences."—New
Scientist "An intriguing collection of
essays detailing the childhood experiences of prominent scientists
and the life events that sparked their hunger for knowledge.
Full of comical and thought-provoking stories."—Globe & Mail "An
inspiring collection of 27 essays by leading scientists about
the childhood moments that set them on their shining paths."—Psychology
The New Humanists: Science at the Edge (Barnes & Noble)
The best of Edge, now available in a book..."Provocative and fascinating." — La Stampa "A stellar cast of thinkers tackles the really big questions facing scientists." — The Guardian "A compact, if bumpy, tour through the minds of some of the world's preeminent players in science and technology." — Philadelphia Inquirer "What a show they put on!"— San Jose Mercury News "a very important contribution, sparkling and polychromatic."—Corriere della Sera
Original essays by 25 of the world's leading scientists..."Entertaining" —New Scientist "Provocative" —Daily Telegraph "Inspired"—Wired "Mind-stretching" —Times Higher Education Supplement "Fascinating"—Dallas Morning News "Dazzling" —Washington Post Book World