In case you don't know what I'm talking about or haven't seen it, here's the link: Does the learning curve imply that different people have different limits in learning a skill. For example let's say there's two people: person A and person B. If person A has a learning curve that is steeper, and lasts the same time or longer than person B, then he will become much more proficient then him, no matter how much person B tries. It will take person B years to become as proficient person A did in a couple of days, since person's B learning curve plateue out at a much lower performance than B. Could this also explain the difference in intelligence of people. People who have mastered basic concepts at a better proficiency, can learn many different complex concepts at a faster rate (for example an understanding of Calculus can make one proficient in physics and engineering).