forum 10: week of March 19 - second order knowledge
I think the forefront that you are thinking of would be the development of meta-awareness which could be defined in different ways. According to Kelp and Pederson, children lack the ability to grasp the concept of knowledge (i.e. knowing about knowing) at a young age. Presumably this skill develops as the brain matures during early childhood. I'm no developmental psychologist but I'd guess that this skill begins to develop around age 3 or 4. I would say that adults (and children who have matured to the point of developing metacognition) can possess second-order knowledge while very young children cannot. I think the KK-principle needs some tweaking to get around this objection.