Left-brained people tend to have suspicious minds. The result (as Elvis sang in 1969) is they’re “caught in a trap.” Doubt it? Click a link and take a test.
Here is a little test created by Edward Adelson, a neuroscientist at MIT (you have to click this link or you won’t get anything out of the rest of this column). This test demonstrates how left-brained people tend to be suspicious. In the test, you see a cylinder casting a shadow on a checkerboard. Square B, under the shadow, appears lighter than Square A. But it’s not. Click right, to the next image.
In the next image, the pixel shade In B is in fact exactly the same as in A. By connecting Square A and B, we see the difference in shading is an illusion.
Say what? Suspicious? Thinking: No way! Welcome to your left hemisphere. It tends to be skeptical, even suspicious. But in Adelson’s illusion, the left hemisphere is dead wrong. Or at least mistaken. Or fooled.
But let’s give the left hemisphere a break. Adelson’s illusion arises because the left hemisphere is not merely absorbing incoming sensory data from the right hemisphere. It is making millions of complex, non-conscious calculations. In the shadow illusion, the left hemisphere is quickly making inferences from past experiences about objects under shadow and compensating accordingly. Past experiences tell the left hemisphere that Square B is lighter.
But it isn’t. Adelson’s illusion reminded me of a line from Elvis Presley’s Suspicious Minds: We’re caught in a trap, I can’t get out. People who bias the left brain are caught in a trap, in “a hall of mirrors,” writes Iain McGilchrist. They only reflect back what they already know they know they know. They find it difficult to consider anything that differs from their past experiences, what’s outside their frame of reference.
That’s bad enough. Suspicion, however, puts the onus on the contrarian voice—McGilchrist calls it “the prophetic voice”—to “prove” it’s right. If it can’t, it’s written off.
My vocation is being a prophetic voice, in business as well as in the faith community. I’ve experienced Adelson’s illusion in consulting. An international company wanted to know why new employees didn’t read the CEO’s book (after five days of being immersed in it during orientation). I suggested three reasons. All three were met with suspicion. Nothing came of my suggestions.
I’ve experienced Adelson’s illusion in the church as well. Suggest that: 1) Western Christianity is in exile, or 2) its ministries are saturated with Enlightenment assumptions, or 3) Western Christianity is an “aberration” (a deviation from the historic faith), and you often get the arched brow of suspicion.
The Enlightenment is based on suspicion of authority. This applies to individuals and institutions. Over the course of 500 years, a subtle bias has become a cultural bias. It has created a left-brained world. Like the majority of Judeans who were suspicious of the prophetic voice (telling them they were in exile), most US Christians are suspicious of the prophetic voice suggesting Western Christianity is in exile. These Christians are sadly mistaken. Adelson’s illusion might give them pause.
 Philip Jenkins, “Companions of Life: What Must We learn, and Unlearn?” Books and Culture, March/April 2007, Volume 13, No. 2, 18-20.