I Used To Be A Fan But I Am Now Shocked, Disgusted And Appalled With Sam Harris

[I_am_not_mafia]

Except that those neural connections are quite literally not there until the brain in question takes an interest in whichever phenomenon it is that spurs the development of those new neural connections. The potential to grow new connections is innate in everyone, sure -- but that potential is weakened by an unstimulating environment, say, or childhood malnutrition. The capacity for growth in intelligence is innate. The actual growth of intelligence largely depends on the environment.

... and existing connections between neurons will strengthen and weaken over time with hebbian learning using a variety of different physical mechanisms, and even reconnect to other parts. Two people could theoretically have exactly the same number of neurons and axons but have vastly different abilities or level of intelligence based on how their brains have been shaped from their environment. One could have a far more efficient brain than the other.

Granted the absence of neuropathology, no doubt your standard-issue human contains a potential for intelligence roughly equal to other humans. But the environment seems to shape the development of intelligence. This is one reason why inner-city children more often need preparatory classes in order to succeed in university.

I personally argue that you only be as intelligent as your environment allows because you need something to be intelligent about, to learn and to adapt to. A baby raised from birth in a sensory depravation chamber won't make an intelligent adult no matter what its parentage.

I do think that there are innate predilections but these only really serve to start the person down the right path. If they don't make use of their abilities then someone without those innate abilities could easily get better than them through hard work and practical experience. Intelligence can also be lost over time. Use it or lose it.