Look at the picture above of the two tables and see if you can determine which of the tops is bigger. Or are they the same size, the same shape?
You probably would say: “Obviously they are not the same shape. The one on the left is clearly narrower and longer than the one on the right.” Or is it?
Now take a piece of paper and either cut out or trace the table top on the left. Then lay your cutout or tracing over the top of the table top on the right. Which is bigger? That’s right, they are both identical.
This picture was created by Roger Shepard, an Oxford and Stanford University professor. We all have seen some of these kinds of illusions over the years, in Readers Digest or e-mail exchanges, and we often refer to them as optical illusions. We would be more accurate describing them as cognitive illusions, because the illusory experience is not created by our eyes, but by our brain. As Shepard says,
“Because we are generally unaware that we are imposing a perceptual interpretation on the stimulus, we are generally unaware that our experience has an illusory aspect. The illusory aspect may only strike us after we are informed, for example, that the sizes or shapes of lines or areas that appear very unequal are, in fact identical in the picture.”
When we look at the picture, having no reason to assume that there is an illusion at play, we don’t even consider that we might be seeing something different than what is obviously right in front of us. The problem is that it is not what is right in front of us at all.
The bottom line? We make assumptions and determinations about what is real every moment of every day. We sort out those 11 million pieces of information, we see what we see, and we believe that what we see is real. Only occasionally do we realize how subjective those determinations are, and how much they are impacted not by what is in front of us, but by what we interpret is in front of us, seen through our own lens on the world.
The challenge is that even knowing that we are inherently biased, we may not be able to help ourselves. According to Shepard,
“Because the inferences about orientation, depth, and length are provided automatically by (our) underlying machinery, any knowledge or understanding of the illusion we may gain at the intellectual level remains virtually powerless to diminish the magnitude of the illusion.”
Our perception, in other words, is so deeply buried in our “underlying machinery,” our unconscious, that even knowing that it is there makes it difficult, or impossible, to see its impact on our thinking and on what we see as real.
Source: 2008 Diversity Best Practices • www.diversitybestpractices.com