Reasons to Believe

Optical Illusion Exposes Reality of Design

Each day new discoveries provide more evidence for God’s existence and the Bible’s reliability—but the research often remains buried in the academic journals. So most people, even scientists, remain unaware of important breakthroughs.

This spring, RTB will launch Creation Update 2.0, a new podcast dedicated to shining a spotlight on these unsung discoveries. Each week Hugh Ross, Jeff Zweerink, and yours truly will record short descriptions of recent but underreported scientific findings and explore their implications for the Christian faith.

In one of the earliest episodes, I discuss a report in the Proceedings of the National Academy of Sciences about the human pupil’s response to light. Common knowledge says pupils constrict when exposed to bright light and dilate in dim light or when exposed to eye-catching stimuli. However, when researchers showed people an eye-catching image with the illusion of brightness, the pupils were tricked by the illusion. Instead of dilating, the pupils constricted.

This is the type of discovery that skeptics often point to as an example of a poor design. Some skeptics argue that seemingly less-than-optimal systems in nature fit better with an evolutionary worldview. They say it’s inconceivable that the biblical God would use substandard designs.

Yet, closer examination suggests that this unexpected pupillary response is a good thing. Damage to the retina is permanent. So, it’s better for the pupils to constrict inappropriately when presented with illusions of brightness than run the risk of retinal damage. Plus, as the researchers discovered, the pupils dilated quickly after the initial constriction in response to the optical illusions. It appears that higher-order processes in the brain associated with the interpretation of visual stimuli function as compensatory designs that override the pupillary reflex when it responds unnecessarily.

As is often the case, careful consideration or more information shows that so-called “bad” designs are, in fact, elegant and highly optimized systems—a conclusion that fits better with the existence of a thoughtful Creator.

Subjects: Life Design

Dr. Fazale Rana

In 1999, I left my position in R&D at a Fortune 500 company to join Reasons to Believe because I felt the most important thing I could do as a scientist is to communicate to skeptics and believers alike the powerful scientific evidence—evidence that is being uncovered day after day—for God’s existence and the reliability of Scripture. Read more about Dr. Fazale Rana