Our perception of the world around us is strongly linked to our vision.
But how do you know what you're seeing is real? Can you really trust your eyes?
Take for example these two grey rectangular columns,
both of which are different shades of grey. Or are they?
It turns out that they're the exact same.
And yet, even after knowing the illusion is there
your eyes refused to see them as the same.
Introducing colors produces the same result.
I promise no trick photography or editing effects have been applied.
In fact, if you look up the Munker-White illusion,
you'll come across many more examples.
Examine them in Photoshop and you can see that the colors are the exact same.
A similar effect can be seen with this checkerboard illusion.
Tile A clearly seems darker than tile B. But you know better by now, right?
Even though your eyes can't see it, you know when I removed the surrounding imagery
the tiles will be the same color. So what's going on here?
The truth is that scientists don't fully understand this phenomenon,
and there are many complex biological and neurological factors taking place.
Ultimately, our brains judge color and brightness in context.
In other words, our brains compare the surrounding environment
in order to create our perception.
The purpose of our senses or eyes in this case,
is not to provide us with an absolute color or physical property of our external reality,
but to interpret what we see as efficiently as possible
in order to interact with the environment most appropriately.
The tile illusion takes advantage of this phenomenon.
Our brains know that shadows make objects look darker,
as a result the brain compensates by interpreting the tile as being lighter
than it appears until we take the shadow away.
Perhaps, the most blatant example
is this gradient.
The middle bar is simply one color.
Remove the background gradient and it becomes obvious. Once again,
the darkness of the background has affected our perception of the bar's color.
Our perception is relative.
So do you still trust your eyes?
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