Anyway, this is a wonderful posting. If sleep doesn’t help with over-fitting, something must. One might wonder how the genetic system combats over-fitting, too. Aside from mutations.

[Funes] was, let us not forget, almost incapable of ideas of a general, Platonic sort. Not only was it difficult for him to comprehend that the generic symbol ‘dog’ embraces so many unlike individuals of diverse size and form; it bothered him that the dog at three fourteen (seen from the side) should have the same name as the dog at three fifteen (seen from the front). [...] He was the solitary and lucid spectator of a multiform, instantaneous and almost intolerably precise world. [...]

With no effort, he had learned English, French, Portuguese and Latin. I suspect, however, that he was not very capable of thought. To think is to forget differences, generalize, make abstractions. In the teeming world of Funes, there were only details, almost immediate in their presense.

Borges mentions sleep in the story:

It was very difficult for him to sleep. To sleep is to turn one’s mind from the world; Funes, lying on his back on his cot in the shadows, could imagine every crevice and every molding in the sharply defined houses surrounding him. [...] Towards the east, along a stretch not yet divided into blocks, there were new houses, unknown to Funes. He imagined them to be black, compact, made of homogeneous darkness; in that direction he would turn his face in order to sleep. He would also imagine himself at the bottom of the river, rocked and annihilated by the current.