There is a deeply rooted certainty within us.
The belief that what we see is reality. That the world exists in front of us exactly as it is, and that our perception records it with relative accuracy. We live with the feeling that if we look carefully at something, nothing important can escape our attention.
In the late nineteen nineties, two researchers, Daniel Simons and Christopher Chabris, conducted an experiment that would later become one of the most famous in the history of cognitive psychology.
They showed people a video in which two groups of individuals were standing and passing basketballs to one another. The instruction was simple: count how many times one team passes the ball. The participants focused, watched carefully, and counted the passes.
And yet, in the middle of the video, right in front of their eyes, a person wearing a gorilla suit walked through the scene, stopped, beat its chest, and then walked away. Nearly half of the people watching the video never saw it.
Not because they weren’t looking.
Not because it wasn’t there.
But because their attention was directed somewhere else.
This phenomenon became known as inattentional blindness. It does not concern the eyes. It concerns attention. The image is right in front of us, but the brain does not process it consciously if it is not related to the task we are focused on at that moment.
Years later, the same researchers gathered decades of scientific findings into a book with a title that became almost symbolic: The Invisible Gorilla. In that book, the experiment stops being just a scientific finding and becomes a way to understand how human thinking works in everyday life.
Because the important part of the experiment is not that some people failed to see the gorilla. The truly interesting part is that most people are certain that if they had been in the experiment, they would have seen it. In other words, the problem is not only that we miss things that happen right in front of us. The problem is that we believe we don’t miss them.
This is perhaps the most dangerous illusion: the illusion of certainty.
Perception is not a mirror of reality. It is a selection. The brain cannot process all the information it receives every moment, so it filters reality. It keeps only what is useful for the task at hand and leaves everything else outside conscious experience.
In other words, we do not see the world as it is.
We see the world as we are able to manage it.
And this does not concern only a laboratory experiment. It concerns the way we listen to the people around us. The way we remember the past. The way we form opinions and certainties. The way we live.
We see what we expect to see.
We hear what we can tolerate hearing.
We remember what fits the story we tell ourselves.
And inside this selective reality we build our sense of truth.
There is a point, however, where this function of the brain becomes a trap. When we forget that what we see is only a part of reality. When the selective image becomes absolute certainty. When we stop asking what it is that we are not seeing.
Then the gorilla may be standing right in front of us —
and we keep counting passes.
And perhaps the most important question is not whether we see the world correctly.
But how many things are happening right in front of us
without us seeing them at all.