And why does the horse abruptly want to unseat the rider? There is a reason, mystery though it is to us. It is our job to figure it out.
The good and the bad of horses is that their thinking power is definite and structured, but also very reactive. Can’t school that out, it’s part of their biology. They react very abruptly to stimuli we don’t notice or don’t consider significant. That is what it is to be a horse. And … to be a rider. A rider, not a passenger.
The horse is never going to solve this or figure it out for us. We are the ones with the big brains, they are the ones with the big hearts. Biologically speaking.