But almost all of the returns to education are captured by the person receiving the education. How much incentive do you need to provide to someone to increase

But almost all of the returns to education are captured by the person receiving the education. How much incentive do you need to provide to someone to increase their own earnings by 50%? If you want to see what happens when a society mindlessly thinks "more kids in more college is better, damn everything else," look at society right now.