Actually it isn't how much they know, but how much they retain. The reason that infants seem to be soo incapable is because their memory span is actually quite short. That doesn't allow them to retain the information that they don't instinctively know. Instinct gives them the ability to want to learn, to eat, to sleep, to pass bowel movements, etc. However, outside of that it's only as they get older, through repeditive behavior (from them and you), and increasing memory do they start to do more that they've learned.
at 6:00 PM on Jan. 19, 2011