A reader sent me this email reflecting on my critique of Amy Chua.  Reprinted anonymously with his permission:

Dear Dr. Caplan,

You speculate as to why Jews are, on average,
successful, and as to whether or not parenting has anything to do with
it. In my experience, there is a distinctive Jewish parenting style
that seeks to motivate kids to achieve, but through a very different
mechanism than the one used by Amy Chua. The mechanism to which I
refer, of course, is guilt.

In my experience tutoring Jewish kids (and, earlier, being one), I
have seen how Jewish kids tend to emotionally punish themselves for
even minor failings at school. Their parents express only mild
disappointment if the kids return with less than an A+, but those same
parents have given such a large amount of positive reinforcement in the
past that the kids feel an almost constant sense of guilt and
obligation. My parents never once scolded me for getting an A- on a
test…but I never got one. I made sure I didn’t, because disappointing
them was something I feared more than any punishment. Yes, it helped
being born smart, but I had equally smart friends whose parents did not
motivate them to apply themselves.

I believe that motivation by guilt – which requires that a parent
be kind and attentive most of the time – is superior to motivation by
punishment, since guilt – or, really, the feeling of obligation to work
for others’ benefit – gets internalized far more effectively than the
fear of an angry mother slapping you. And in the long run, positive
motivation beats negative motivation every time.

My reply:

Thanks for your comments.  But why not just say that Jews are
genetically inclined to Neuroticism, so little punishment is required to
motivate them?  This would fit with the fact that Jews (well, Jewish
men) earn much more than you would expect, even controlling for IQ and
education.  And if Jews would feel this way in virtually any family, in
what sense is Jewish parenting the cause of their success?