From Live Science:
“…In an experiment, scientists gave cats string with a treat on the end. The cats would pull the string and get the treat. Faced with two strings — one bearing a treat, the other not — the cats were befuddled.
Dogs figured the two-string experiment out, however. “Cats do not understand cause-and-effect connections between objects,” the researcher says. Perhaps that explains how they can sneak up and scratch you, again and again, even though you make it clear you do not like it. Dogs, well, they learn to please, don’t they?
A study in 2007 found dogs could use touch-screen computers to accurately classify color photographs by recognizing the concept of a dog vs. a photo with no dog….”