I decided to see what would happen if I put a bunch of balloons in my paddock. Predictably, Obie, the bold-as-brass Paint, approached them immediately and decided they were not only fun, but HIS! Also predictably, my scaredy-cat darling, Gryphon, wouldn't come anywhere near the bouncing, brightly-colored, horse-eating THINGS. I was pleased to see that my pony, Twister, was quite curious and would have touched the balloons had Obie not chased her away. Rogie did manage to get his mischievous little muzzle on them at one point, causing the demise of the "I love you" heart balloon.
So, to the people who say that the way a person's horse responds to things is a reflection of the person, I say, "What does that make me -- a split personality?"