In noting President Obama's prominent use of "caricature" in his Notre Dame speech counseling people against demonizing those with opposing views by resorting to "caricature", I was prompted to look into the etymology. The sense of "overloading" an image with exaggerations, I now realize, really should evoke the simple noun "cart". And in the oldest root, Proto-Indo-European root *kers- , we are really looking into the heart of the matter. The cart is the perceived enemy or target of our disdain or humor (with intent to poke fun or demonize), and we proceed to OVERLOAD that "cart".