(NEW YORK) -- George Zimmerman faces charges of second-degree murder for fatally shooting Trayvon Martin in Sanford, Fla., on Feb. 26. And though Zimmerman has yet to appear before a jury, many people, with little firsthand knowledge of the case, have already judged him guilty or not guilty.
Psychologists say this rush to judgment is part of being human, and we do it all the time. Think of Amanda Knox, former Rutgers student Dharun Ravi or even former IMF chief Dominique Strauss-Kahn, arrested on charges -- later dismissed -- of sexually assaulting a New York hotel maid.
"Judgments help us make sense of things. We tend to be uncomfortable if we don't know what to think," said Nadine Kaslow, a professor and chief psychologist at Emory University's Department of Psychiatry and Behavioral Sciences. "On the other hand, sometimes we quit seeing the whole picture, quit seeing the complexity of the story and rely on our biases."
It's a tendency we can't help, said psychologist Daniel Khaneman, Nobel laureate and professor emeritus at Princeton University.
In his book, Thinking, Fast and Slow, Kahneman describes the brain's innate tendency to function in two ways: There's fast thinking, the intuitive, emotional gut reactions formed seemingly without effort, and slow thinking, the deliberate, rational musings that try to take all facts and perspectives into account.
It is the fast thinking side of the brain that works from emotions and preconceptions to form our own story for a particular event.
"We couldn't get by without fast thinking. We can't always analyze evidence over time. We have no choice but to operate mostly in fast thinking," Kahneman said. "It does occasionally get us into trouble."
Kahneman said fast thinking probably played a role not only in how people see Zimmerman's defense, but also in how they interpret Zimmerman's actions that February day when he shot Martin dead.
The shooting was likely "emotional, very fast and not based on careful consideration of the costs and benefits and risks," Kahneman said.
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