If you're like me, this question made you curious. So let's leave the world of cats for a second and consider the meta-question: What kinds of things make people curious?
Psychologists have wrestled with this mystery for many years. In 1994, George Loewenstein, a behavioral economist at Carnegie Mellon, came up with a theory of curiosity. He called it the "information-gap theory." He said that curiosity is simple: It comes when we feel a gap between what we know and what we want to know. And he goes further: He said that the gap actually causes us a kind of pain — like an itch that we need to scratch. And that's where the "fire" of curiosity comes from — we are driven to fill the gap, to scratch the itch.
Notice that to create curiosity you've got to focus people's attention on the gap. For instance, there's a book called, Why Do Men Have Nipples? That's a solid question. Chances are, you don't have an immediate answer. And yet you weren't frothing with curiosity about the man-nipple-problem until the book title called attention to the gap in your knowledge. You know something: Men have nipples. You don't know something: Why. That's a gap.
Are cats right- or left-pawed? It's another information gap. You know something: People are "handed." You don't know something: Does that apply to cats, too?
And the gap creates the itch. That's why teachers, in particular, should get familiar with the information-gap theory. If students feel the itch, they'll expend effort to scratch it — and effort is a precious resource. The cat-paw mystery, for instance, can be used to teach the scientific method. Here's an experiment that teachers can assign to their students to investigate the matter.
So are cats left- or right-pawed? The consensus seems to be that, yes, any individual cat has a paw preference. Opinion is mixed about whether cats, as a species, favor one paw over another, the way that humans skew right-handed. (Although, confusingly, this Turkish study seems to imply that most cats are right-pawed.) Bottom line: If you dangle string in front of your cat, it will probably tend to favor one paw with its swats.
Here's a confession (or perhaps a testimonial for the information-gap theory): Once I started researching cat-handedness (or pawedness) I couldn't seem to stop. This is the kind of unfortunate behavior that the internet enables all too well. So here's another gratuitous information gap: How would you go about testing whether a chimp is left-handed or right-handed? (Again, notice that you'd never lose a minute of sleep worrying about this until the gap is opened, and then you start to wonder...)
Answer from William Hopkins, a psychologist at Berry College in Mount Berry, Georgia: "A common experiment he uses to test for handedness is giving a chimp a long tube with peanut butter lodged inside. If the chimp holds the tube with its left hand and probes for the peanut butter with its right hand, the animal is likely right-handed. Hopkins has found that the chimps almost always attack the peanut butter this way."
One more information gap for the road: "A study on toads found the creatures mostly used their right legs when removing a plastic balloon that researchers had wrapped around their heads." (source) Question: Where can you get the video of researchers wrapping plastic balloons around the heads of toads?
Books mentioned in this post
Chip and Dan Heath is the author of Made to Stick: Why Some Ideas Survive and Others Die