I say genetics is a major factor in intelligence. <br>Let's take the example of Jay-Z: he grew up in the ghetto in NY, as a drug dealer. But yet had the (genetic) intelligence to become a billionaire. He is articulate, wealthy, business savy, runs a multi-billion dollar empire, great at public speaking, he's driven, etc... <br>When I compare Jay-Z to myself, I grew up in the suburbs, in a very safe city in Ontario (Canada), in a middle class family. but I'm not a billionaire, I'm terrified of public speaking, i couldn't run a business, I'm nowhere near as driven as him, etc...