You might actually be able to do some back-of-the-envelope calculations on this. Humans are slow learners, and end up with reasonable ontologies in a finite number of years. By this old estimate, humans learn two bits worth of long term memory content per second. Assuming that people learn with this rate during 16 hours of waking time each day of their life, this would end up something like 32 megabytes of accumulated permanent memory for a 13-year old. 13-year olds can have most of the basic world ontology fixed, and that's around the age where we stop treating people as children who can be expected to be confused about obvious elements of the world ontology as opposed to subtle ones.

Hand-crafting a concept kernel that compresses down to that order of magnitude doesn't seem like an impossible task, but it's possible there's something very wrong with the memory accumulation rate estimation.