I think people are naturally ignorant by choice to a point, because if you become educated about something, say victims of a disaster or kids who are starving in Africa, then you have a moral obligation to try to do something about it. If you aren't aware of the problem or don't make it a focal point, the human mind doesn't feel like it has to do anything. And with all the deep heavy problems in the world, you can't help everyone. If you try to help people more than you are individually able you will surely become deeply depressed and hating yourself and your fellow man. Ignorance keeps us happy.