Horses learn immediately from their mothers.
Within an hour, they’re frequently able to stay with their mother and run with the herd. This is important of course, because they don’t want to get eaten. They learn immediately from the other herd members how to behave around each horse differently. If they don’t, they’ll be missing some hide in the shape of a hoof or teeth.
People…yoikes. After eighteen years we’re just getting out on our own. Even then, we hardly know which end is up and rarely handle dealing with others well on a consistent basis. After 40 or 50 years, we may, if we’re paying attention be able to deal with a 6 month old colt who is way smarter than most of the people in it’s life.
So, when you want your horse to do something and you think he’s not paying attention or not doing it… you’re probably right! Because he’s probably already learned that he doesn’t need to. Also, if you’re learning some skill and you think your horse should ‘get it’. Ponder how many times your riding instructor/trainer has told you something (like sit down in the saddle) over the years. How many times??? And still you are up? Still?
Horses are easy. People…