I wouldn’t have seen it if I hadn’t believed it

No one is above self-delusion.

This thought kept buzzing in my head as I was doing research related to a book I’m currently writing. Brilliant scientists—on a regular basis—fool themselves.

We tend to think that we’re above cognitive biases and subjective distortion. The “I’m not biased” bias is a real thing. Studies show that people regularly rate themselves as less biased than the average American. These studies remind me of how President Dwight Eisenhower was astonished to learn that half the U.S. population had below-average intelligence.

But scientists should be in a different category. After all, they’re trained in the scientific method designed to counter human biases and help separate fact from fiction. Yet, scientists aren’t immune from seeing what they want to see—even when it’s not there.

Consider these examples, all of which are about Mars.

In the late 1800s, the Italian astronomer Giovanni Schiaparelli spotted what he called canali on the Martian surface. These canali—not to be confused with the delicious Sicilian dessert cannoli—were long, canal-like structures.

Although Schiaparelli didn’t attribute these canals to intelligent life, the astronomer Percival Lowell later took that leap. Lowell wrote that the canals were built by an ancient intelligent civilization in order to access water from Mars’s polar ice caps. Lowell’s speculations fueled the public’s already voracious appetite for alien stories, providing fodder for numerous media stories and science-fiction books like Ray Bradbury’s Martian Chronicles.

But the canals turned out to be optical illusions.

Mars also led Nikola Tesla, the inventor of the AC motor, astray. Tesla reported detecting signals from Mars consisting of a “regular repetition of numbers,” much like how Jodie Foster’s character in Contact detected prime numbers from Vega. Tesla interpreted these numbers as “extraordinary experimental evidence” of intelligent life on Mars.

More recently, scientists at Stanford University picked up a signal from the Mars Polar Lander after the spacecraft was thought to have crashed on the planet’s surface. To verify the signal’s origins, they told the spacecraft to send smoke signals by turning its “radio on and off in a distinctive sequence.” The spacecraft appeared to oblige. The scientists received the smoke signal and announced, much like Dr. Frankenstein, that the spacecraft was alive.

But it was not. The signal turned out to be a fluke.

The Stanford scientists were experiencing a phenomenon known as “I wouldn’t have seen it if I hadn’t believed it.” They wanted the Mars Polar Lander to be alive so badly they saw what they wanted to see.

None of these scientists were intentionally trying to mislead the public. Their conclusions were based on their interpretation of seemingly objective data. So how did these brilliant people see something when there was nothing?

We tend to assume there’s a negative relationship between intelligence and cognitive bias. In other words, we believe that the more intelligent you are—the more advanced your operating system is—the less likely you are to fall victim to the type of fallacies that affect the rest of the public.

But the opposite is true. As Tali Sharot explains in The Influential Mind summarizing the relevant research, “[t]he greater your cognitive capacity, the greater your ability to rationalize and interpret information at will, and to creatively twist data to fit your opinions.”

So if you think you’re immune to fooling yourself, think again. No one comes equipped with a critical-thinking chip that diminishes the human tendency to let personal beliefs distort the facts. Regardless of your IQ or intellectual capabilities, physicist Richard Feynman’s adage holds true: “The first principle is that you must not fool yourself and you are the easiest person to fool.”