Previously, I posted about our unfortunate tendency to fear unlikely diseases over the more common killers—and how if we put our focus more intently on preventative measures that stave off likely illnesses, we’d be better off.

Humans like to fear the irrational over the rational, it seems.

Just as we fear high-profile illnesses over less common diseases, we fear unlikely accidents over more realistically unintentional killers:

• Sharks: Scarred by watching “Jaws” and “Piranha” at too tender an age, I fear natural water. I’m not alone: Many Americans report a fear of shark attacks, although the International Shark Attack File reports only 1,909 confirmed shark attacks worldwide between 1580 and 2003—making the odds of a shark attack one in 11.5 million.

• Airplanes: Reports estimate that 30 million Americans are anxious air travelers. Yet an aviation safety expert Arnold Barnett estimates that the actual risk of involvement in a fatal airline accident is once in every 19,000 years—and that's if you flew daily.

• Natural disasters: News programs, Hollywood, and television nature programs tantalize the world with the destruction of natural disasters. The result? Widespread fear of tornados, flash floods, earthquakes, tsunamis—and so on. Yet the odds of dying in a natural disaster are around 1 in 3,357.

You’re more likely to die in a car accident (42,000 annual deaths). Add in alcohol or texting and the likelihood skyrockets. Firearms are another leading cause of accidental death (650 dead each year). And how about falling (25,000 deaths per year)?

Almost every single day, I encounter slippery stairs and drive a car. (Fortunately, I have no interaction with firearms.) Yet each time I approach descents and vehicles, I don’t feel twinges of anxiety.

And quite likely, I don’t take the full precautions I should to counter their dangers. I read while walking down the stairs—or carry armloads of unbalanced items. While driving, maintaining constant vigilance and awareness proves difficult.

Psychologists hypothesize that exposure, environment, and previous experience cause people to fear unlikely dangers over realistic possibilities. We don’t encounter deep water and natural disasters much, but we coexist daily with automobiles and stairs. More exposure equals less inhibition.

Makes sense. And perhaps consciousness of a fear’s irrationality helps counter it. As the saying goes, awareness is half the battle.

Do you have any irrational fears?