Many years ago, there was a very famous Krautisch horse who could do sums ...
His owner would ask him, "Hans, what is three plus four"? And Hans would clop his hoof, once, twice ... while carefully watching his owner ... six, seven, and stop! Hans having observed his owner's eyebrow moving ever so little.
Of course, if Hans couldn't see his owner's face, his accuracy tanked.
Clever Hans was known the world over, LOL!
Aah!
You read my mind.
Go see the link up there, Blue Dragon.