He meant something more meta I believe. Knowing you are a monkey is one thing, and knowing that you know you are a monkey is a another thing. It's about being cognisant of the fact that there is something called knowledge and you have it

Precisely. To put it more concretely: it is no small feat to grasp the abstract distinction between known-knowns, known-unknowns, unknown-knowns, and unknown-unknowns. They do not know what they do not know.