It's easy to think of cats as dumb compared to dogs. A lot of people generally assume dogs are smarter because we can more easily train them. People train dogs to find bombs, drugs, money and even food. They're assistance animals for disabled people. Does anybody train cats in these ways? There are a few assistance cats out there, but in general, no. So, on the surface, dogs appear smarter than cats.
Many of us have seen videos of cats figuring how to get out of cages, or otherwise solving complex problems. We may have even seen this display of intelligence in our own cats at home. Dogs might be smart, but can they solve complex problems? Maybe, but the stories don't make the rounds as much.
Cats' brains are smaller, as a percentage of body size, than dogs' brains and even our brains. That, too, could lead people to believe that dogs are smarter than cats. However, the size of the brain compared to body size doesn't always indicate higher intelligence. According to an article in Psychology Today, Neanderthals had brains larger than ours, and yet they couldn't adapt quickly enough to survive, and died out.
The Psychology Today piece also mentioned that cats have almost twice as many neurons in the cerebral cortex as dogs do. While that isn't necessarily a concrete indicator of overall intelligence either, it does mean that cats have a higher learning capacity than dogs. The cerebral cortex is the center of things like complex problem solving. So, is it any wonder that a cat can actually figure out how to open a door, a cage, or get out of a confined area on its own?
Joan Liebmann, a medical sociologist, wrote an article in The Huffington Post that discusses the issue also. She says it's more likely that cats and dogs have different types of intelligence, which makes it harder to compare them. So which is smarter? They're both very smart, in their own way.