Seeing is believing. But what is seeing?

The Kanizsa triangle illusion

Take a look at the figure on the right.

What do you see?

Most of us would say that the figure is made up of five elements: three small and solid black circles, one triangle outlined in black, and another white triangle, laying on top of the other four shapes, partially obscuring each.  The outline of the white triangle is somehow visible, even though we can’t find one when we look closer; the white triangle even looks brighter than the background, which seems like a very light grey in comparison.

But, of course, none of this is actually true.  There are no actual circles, only three Pac-Man shapes, like pies with slices missing.  There is no black triangle, only three V-shapes facing each other.  And there’s no white triangle at all, not even a piece of one.  Nor is the triangle that we perceive any different in color and brightness than the area that surrounds it.

This is the illusion known as the Kanizsa triangle, created by an Italian psychologist named Gaetano Kanizsa in 1955.  Many similar images have been created since, by researchers fascinated by the workings of our visual perception.  The illusion clearly demonstrates our propensity for seeing things that aren’t really there.  Even when the reasoning part of our brain knows the white triangle is just an illusion, we still persist in seeing it.

That doesn’t make us out to be a bunch of hallucinating zombies (though some mornings I’m not so sure).  It means that we are complex, intelligent beings who are constantly making sense of our world.  The more I learn about human perception, the more in awe I am of the wondrous creatures that we are, and of the wondrous Creator that made us.  Most of the time, we interact so seamlessly with our environment that we don’t notice the moment-to-moment miracle of being able to do so–until some clever experimenter comes along and draws back the curtain.

Illusions reveal our perceptual habits, the ways our brains make sense of what we see.  And most of the time, in real life as opposed to psychology experiments, our perceptual habits work.  Let’s face it: if you actually encountered something like the Kanizsa triangle outside a laboratory, it wouldn’t be because you happened to stumble into a conversation between three Pac-Men.  It would be because somehow, things with relatively regular shapes happened to come together in that way and in that place.  Our brains would get it right.

Most of the time.

The general principle is that we don’t just passively receive information from the world around us; we are actively making sense of that information, all the time, on the basis of how God has “wired” us and our previous experience.  If we didn’t learn from past experience, every situation would become a new problem to solve, and life would pretty much grind to a halt.

But sometimes, we get it wrong–especially when it comes to making sense of other people and their motivations.  Part of me is absolutely certain that when my wife checks in with me to make sure that I will take care of a particular household chore, she is criticizing my competence (note to some of the wives who are reading this right now: please stop rolling your eyes at husbands in general…).  Another part of me knows that this is just an illusion, a habit of thought that I bring to the situation.  And it takes an act of will to set the illusion aside in favor of what I know to be true: that my wife is merely asking me if she can cross that particular chore off her mental list, so she can move on to other things.

My habits of seeing generally serve me well.  I wouldn’t make it through the day without them.  But they can be fooled.  May God grant me the wisdom to know when my illusions are getting in the way of reality, and the humility to let them go.