The Nurture Assumption: Why Children Turn Out The Way They Do Judith Rich Harris (1998) Bloomsbury: London Official website ~~~~~~~~~~~~~~~~ http://home.att.net/~xchar/tna/ Tom's summary ~~~~~~~~~~~~~ The nature-nurture dichotomy is a false one. It suggests that those effects on a child not due to genetics are due to parental influence. Environmental influences on how children turn out also include many factors other than parental influence, the most important being the influence of the child's peer group. JRH argues, that despite decades of research there is no convincing scientific evidence that parenting behaviours have more influence on the way children develop than their peer group. All existing research either confounds genetics and nurture (eg clever kids have clever parents *and* clever genes) or confounds nurture and peer-group (eg hard working parents send their kids to schools of hard-working kids). 'Group Socialisation Theory' proposes that kids have an evolutionary instinct to learn from their peer group, and to what to be like them. Children are acutely socially aware, able to change behaviours depending on social setting. Behaviours learn from parents may not generalise outside of the family. Example: immigrant parents speak their native language. The children will end up being fluent in the language of their adopted home, not their parents language. JRH gives a severe critique of developmental psychology and the history of child-rearing advice. She also discusses an evolutionary perspective on human psychology, including our motivation to identify with a group, to imitate our group and feel animosity to those outside of our group, and what determines which group we identify with. Interesting/COOT-relevant bits ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - p42 Birth Order Effects: decades of research 'a waste of time and paper'. No evidence found that birth order affects personality [see Appendix I for convincing discussion of the evidence] - p60: example of child, Andrew, who learnt depressed manner from his (postnatally) depressed mother. "The somber faces and muted movements common in the babies of depressed mothers are "specific to their interactions with their depressed mothers," according to researchers who studied babies like Andrew" - p90-95 Child rearing practices in traditional societies - p324 discussion of inheritance of being overweight Note on my notes ~~~~~~~~~~~~~~~~ These are not intendended as a comprehensive precis of the book. Instead they can be used as a rough guide to what is where in the book, or considered as marginalia. Foreword: Steven Pinker ======================= Nature vs Nurture sidelines non-parental/nurture environment Theory: Parents do not influence children's personality, it is their peers. - Fits with humans as living in social groups Offspring and parents have non-coincident genetic interests We would not expect evolution to make children putty in their parents hands Preface ======= How this book got written. interesting story! 1: 'Nurture' is not the same as 'Environment' ============================================= Nurture implies 'influence of parents' (legacy of freudianism) + more on history of psychological research 2: The nature (and nurture) of the evidence =========================================== socialisation research vs behavioural genetics most socialisation research confounds parental behavioural influence with parental genetic influence additionally child temperament affects parental behaviour (ie causation is not proved) p31 direct vs indirect genetic effects, "hereditary" is conflation of the two ie genetic component of personality derived from behavioural genetics includes some (evoked) aspects of parenting style. The remainder of variation must be due to aspects of the environment which cannot be affected by genetic components. 3: Nature, Nurture, and none of the above ========================================= The flip side of remarkable similarity of twins reared apart: Twins reared together are no more similar - often have differences. Tie identical parental environment does not make children more alike p42 Birth Order Effects: decades of research 'a waste of time and paper'. No evidence found that birth order affects personality p44 50% - 66% of two child family parents admit that they prefer one child to the other. Of these parents a 'large majority' preferred their second born. Review of fixation of scientists with influence of parenting style and failure to find solid evidence for any effects. 4: Separate Worlds ================== Children, even more than adults, are adept as being different people with different company (Possibly relates to a tendency to under-generalise learning across contexts) - Acting different roles (different personalities) with parents, peers and siblings [Tom's thought: is development of more consistent personality allowed by development of self-awareness that is associated with ToM?] p60: example of child, Andrew, who learnt depressed manner from his (postnatally) depressed mother. "The somber faces and muted movements common in the babies of depressed mothers are "specific to their interactions with their depressed mothers," according to researchers who studied babies like Andrew" p62 Hence popularity of birth order research: birth order effects *are* consistently found if ask siblings to rate each other's personality. The stereotypes do exist - they just don't generalise outside of the intra-sibling relationship. p70 Bilingualism as a good example of context-specific socialisation. Children can learn two languages, or two styles of language, from parents and from peers. The stronger is the language of the country they live in (language of the peers). - Hearing children of deaf parents raised with no communication except of the most rudimentary sort between parents and child still learn spoken English. How? From peers p74 Extreme situationism: personality results only apply in context that test done p75 [This is dubious! Existence of priming by context doesn't prove that there is nothing but context to personality. Yes, context is powerful, but context is also more than physical socio-geographic location. It exists in our heads, we carry it around and in this way it can be ever-present] 5: Other times, Other places ============================ p78 ff review of historical and cultural variation in child-rearing advice, and of the unfortunate history of child-rearing advice (often inspired by theory, rather than experience) p90-95 Child rearing practices in traditional societies - v. interesting 6: Human Nature =============== p109 Human history is one of group conflict Evolutionary psychology: the 'cognitive arms race' of evolution was not so much to live within groups, but to win while fighting other groups. Hence a) psychological adaptation to group identification etc b) intra-group solidarity and inter-group animosity. note on the way group war-fare would accelerate evolution: xenophobia is an isolating mechanism, war & genocide increases selection, group contrast effects & sexual selection would drive unique group characteristics] p117 ToM & higher cognitive abilities allows group identities larger than personal recognition [remember Steve Jones: amazing genetic similarities of humans - we are all one group!] p118 driving force of brain evolution in humans was dealing with social, not physical, environment p119 Four reasons for offspring not to be overly influences by parents 1. peer learning is quicker, and less at risk of being outdated 2. it increases variability. Parents already have genetic influence 3. can't depend on parents being alive 4. there is a genetic divergence of interest (a la Trivers etc because a child wants a disproportionate amount of parental investment, the parent would like to distribute it most effectively between themselves, and all existing and possible offspring) 7: Us and them ============== p139 group behaviour has a long evolutionary history -> 'group socialisation theory of child development' children are very good at 'code-switch' between social contexts (eg using different language and norms inside and outside the family) 8: In the company of children ============================= p154 Harlow's rhesus monkeys. Peerless monkeys nearly as maladapted as peerless + motherless monkeys when introduced to group living Dr Kellog raised a chimp alongside his own son. The son imitated the chimp more than the chimp imitated the humans! Human children will play away from parents at a comparatively younger age than chimpanzees (which won't be separated until adolescence) p165 children categorise by age. Learning by imitation is important. Age categorisation aids knowing who to imitate p168 personality as a social phenomenon: children wan tot be socialised by their peers - and mercilessly persecute differences 9: The transmission of culture ============================== p205 Transmission of culture: culture passes from age varying children's groups to adults (not from adult to child, but from children's groups to successive adults-who-once-were-children!). 10: Gender Rules ================ innate differences between the two exaggerated by group socialisation by gender 11: schools of children ======================= children's groups form around salience common features, and group contrast effects act to emphasise/exaggerate these common features or value. Which group/category is most salient can vary, if there aren't enough children it won't be boys vs girls but kids vs adults. If there are lots of children (eg high-school) many groups will appear based on temperament, race, etc. 12: Growing up ============== teenagers as a new group. Kids who've learnt the rules but aren't adults yet. Need group-specific identifying features, hence rapid turnaround of pop culture. A mechanism for social change! 13: Dysfunctional families and problem kids =========================================== Biology is not destiny - just because it is inherited doesn't mean it can't be changed psychologists persistently ignore the genetic influence of parents (in favour of the nurture assumption) p292 heritability of obesity is 0.7 (higher than most personality variables) p324 discussion of inheritance of being overweight p325 'why pop psychology blames mom and pop' 14: What parents can do ======================= p327 misery doesn't have to sequelae - it can be important. you relationship with your children is important...for your relationships with your children! relationships are distinct from groupness (and it is groupness that influences which habits/identities persist into adultness). 15: The nurture assumption on trial =================================== p351 "parenting has been oversold... Kids are not that fragile" "the Nurture assumption is the product of a culture that has as it's motto 'we can overcome'" p356 mistaken assumptions - assuming that the nuclear family is the natural 'environment' for a child to grow up in - assuming that a child will copy everyone in their society. Because acceptable behaviour depends on who you are, the child must learn/choose *who* to copy, who is their social category - assuming that things leant in one context will be generalised to all others - insufficient account given to genetic/herititary influences - ignore our long evolutionary history of group living cognitions about relationships are more accesible to consciousness than cognitions about groupness.