No, I mean that I think that P(low education|group of humans who can't understand sorting)>P(low intelligence|group of humans who can't understand sorting).

The 'group' part is important; while education is often constant or near-constant among a community, intelligence is often not; thus, something that is true for an entire group is more likely a result of education than intelligence. Similarly, 'humans' is an important word, because I know that many humans are capable of sorting, and thus there is no species barrier.

Having said that, "low energy" is almost certainly also a contributing factor.