Oh dear god!
In ancient Pompeii, most of the citizens were illiterate... so the signs to the popular red-light district were clearly marked with large penises carved on the city walls, pointing like arrows... the city fathers didn't want you getting lost on the way to the brothel, there....
They were geniuses. Quick as a whip. They used the stars to map things. Discovered things way before the Europeans did. It's a shame they saw them as "uneducated savages". Who knows what intellect they could have shared with us if the Spaniards hadnt destoryed nearly all their documents.