When I was a kid, I was enamored of cigarette-smoking movie stars. When I was a teenager, some of my friends began to smoke; I wanted to smoke too, but my parents forbade it. I was also intimidated by the ubiquitous anti-smoking commercials I saw on television warning me that smoking causes cancer. As much as I wanted to smoke, I was afraid of it.

When I started college as a pre-med major, I also started working in a hospital emergency room. I was shocked to see that more than 90 percent of the nurses working there were smokers, but that was not quite enough to convince me that smoking was OK. It was the doctors. Eleven of the 12 emergency room physicians I worked with were smokers. That was all the convincing I needed. If actual medical doctors thought smoking was safe, then so did I.

I started smoking without concern because I had fallen prey to an authority bias, which is a type of cognitive bias. Fortunately for my health, I wised up and quit smoking 10 years later.

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