The image above clearly shows what’s going to happen next: Splat! Kerplunk! Why is it funny when people fall or trip over themselves? According to Scientific American, we all develop a sense of humor (some worse than others…) and the first requirement for the illicitation of laughter is something called a “play frame.” A real-life, non-serious event would fall into such a category as no one is actually harmed and nothing serious is destroyed. Otherwise, the reaction would be far from humor due to our ability to empathize grief and pain. So, miss-slippery-heels there can slip, flail her arms around, and fall without an injury and it would be a play frame that would likely cause a few snickers and giggles. Should she be seriously injured, however, the reaction would be quite different. Perhaps an, “Oh shit!” Maybe a call to the paramedics.

The next requirement, aside from play frames, is incongruity. In this case, incongruity is the irregular instance where the woman slips and falls. Though I’m sure it happens every day, falls are still uncommon enough (since we’re all experts at walking by the age of 3 or 4) to cause a brief and startling reaction. In conjunction with play frames, there is the beginnings of a recipe for laughter or humor.

Finally, a theory by Scientific American suggests that the idea of mirror neurons, the part of the brain which allows us to empathize and “feel” what someone else is feeling, make is a little more humorous, too. When we look at the image of the lady slipping, or perhaps see someone else stumble out in public, we can almost feel exactly what they’re going through. That, coupled with incongruity and a play frame (a surprise which yielded no injury) might cause us to laugh just a little… perhaps deep inside.