Maybe you’re mentally arranging your to-do list, or rehashing an imaginary rant about something that happened at work, or just daydreaming with the sun on your skin. But that’s when the UPS truck backs over the trash can. Or the wild turkey drops out of a tree on top of your head. Or some kids on dirt bikes come screeching out of nowhere. Life is just a bit more complicated if you’re on top of a horse.