[brc]

I would say it is less than that.

Leaving aside heritability, the environment in which the child will grow up is more or less set in concrete by the time they are born. This includes the parents socio-economic level, but more importantly to that, their attitudes towards relationships, learning, critical thought, reading, victim vs control personality and plenty more. A house without books doesn't fill with books when the child arrives.

Pretty much by the time the first cry is made, a huge chunk of their future is already written. The margin is small, but, having said that, small changes at the margin can make a big difference in individuals.

[turnip1979]

The margin is larger IMHO. I'm a professional scientist and I have no one remotely resembling an academic in my extended family. Now I'm not a textbook example of success but I've read about many other scientists in similar boats: Feynman and Tesla both come to mind. Feynman had an electronics hobby as a kid. Tesla's father was fairly set against him becoming an engineer.

I know some people with amazing private school education flounder because of it. They saw crazy competition early in life and it seems decided to settle. I had very little competition in my early years. Being the smartest kid in your undergrad makes you feel really good, and motivates you to do better. Where I really needed guidance is going from the sheltered world to reality (early 20s .. when I entered the workforce and subsequently made the decision to get a PhD).

What I want to try to do is teach my kid to have her own hobbies and be generally happy in life.

[mcphage]

> Being the smartest kid in your undergrad [...] motivates you to do better.

I've known a number of people to whom it did the opposite—they were always the smartest person in the room, so when they said something, people just assumed they were correct. And they began relying on it; nobody would call them on their bullshit, so they never felt the urge to think very hard about things. Whatever they came up with, they'd think "well, I'm the smartest person around, so I must be right", and that's as far as they'd get.

One guy got very argumentative about it; he'd say the stupidest things, and didn't know how to handle being wrong. Other people figured it out.

[brc]

That might be your specific interests but I'd wager you didn't come from a family with anyone in jail, your parents sent you to school and stressed its importance, and were well read for their education level.

Of course outliers exist and some very successful people come from very dysfunctional families. But if you look at enough people, they come out in temperament and attitude very similar to their family. The really surprising thing is how often one family will produce two top level musicians or sports players.