Nature, nurture, genetics, upbringing. Matt Ridley confuses the issue. By bring more information to the party

So I'm reading a massively interesting book about the brain, in the context of Evolutionary Psychology, "the Agile Gene".  It also has some biochemistry in it, but it's worth the struggle.  I quite like evolutionary psychology - not sure why, perhaps it's how the ideas are strung together, I enjoy Psychology and the evolutionary aspect of it is interesting.  It really complicates ideas, though - as with most people, I had a fairly "nature" "nurture" style separation in my head, not thinking it was really one or another but a combination of both.  But it is actually a lot more complicated than that - an example is people who grew in the womb in the third trimester in a famine.  Shortly after they were born the famine ended and they have a significantly higher chance of diabetes when they get older.  A working hypothesis seems to be that the child is constructed in the womb in reaction to the external famine, but then afterwards when it finds ample food due to the difference between the design and what was there.

Both nature and nurture, a seriously complicated interplay between environment and genes, an environmental effect during gestation that played out in the end of life.

But this famine seems to have a second generation effect - the children who were in gestation during the first 6 months were small children, but grew up normally.  They also have small children themselves.  It's not unprecedented in animals, locusts take a few generations to switch from quite, reticent animals to eat-everything-around.  But second generation influences?  Environmental components of who we are are taken somehow directly from our grandparents' environment?  So not only is nature and nurture a false dichotomy, they actually play with each other - nature and nurture influencing genetic responses, but grandparents environment effecting the way we grow.

I think what is getting me, and that I'm not expressing it well, is that nurture implies some sort of choice, training, but actually nurture, environmental interplays, can be as dictatorial as genetic expressions.  Homosexuality has a component of environmental factors about it - for each older brother a boy has, the boy is around a third more likely to be gay.  So is it the parents' fault a child is gay?  Well, sort of.* 

Also, how much stuff they know about the brain is immense.  They did some experiments on mice, blindfolded them from birth, and found if they were blindfolded for 2 weeks, they could see, if they were blindfolded for 3 weeks they were blind.  Fairly astounding itself, but they actually went in and found the chemicals that did that.  It also has a human component, and a rather tragic one.  Occasionally children are born with cataracts over both eyes and initially the standard practice was not to remove them until the child was 10.  Those children never really learnt to see.

This is all in context of imprinting, which is a fascinating subject itself - how humans imprint, how some parts of our "personality"** are mailable but once set become set in stone.

Sometimes I think the reason I started all this reading about psychology was to see how much we can dictate who we are - can we decide to be different to what we are?  How much can I decide to be different?  And the question still stands, sort of - I want to know what is stuck and what can shift, what we can choose to change.  There are ideas that we are stuck as we are, ever destined to repeat the same cycles, and then there's the more optimistic "we can be whoever we want to be", or as the NLP people put it - if any human can be something, then so can I.***  And it's after reading things like this that I realise I'm probably not asking the right question.  The problem is, I'm not really sure what the right question ought to be.

*Also, my little brother is 1/3 more gay than me, proven by science.

**Personality is a little awkward a word - I wouldn't usually use it in the context of sexual preference, for example.  I would usually put something in like "self" but given I've been talking about development of bodies I didn't want the mistake of people thinking I was talking about anything other than brain-related activity.

***Neither of those are true, by the way.  We are limited, but only somewhat.  And being different is a trick.