The facts notwithstanding, I believe that a majority of people unthinkingly delude themselves about their mortality — meaning that they act as though they believe they are immortal. Of course, they don’t consciously admit it, at least not to others.

I’ve known more than one person who acted as though he believed he will be the first human being to live forever. When I say acted, I’m referring to lifestyle. Why else would an individual smoke, take drugs, drink excessively, or eat a diet loaded with saturated fat, cholesterol, salt, sugar, and processed foods?

A wise philosopher friend of mine once asked me who the biggest mass murderer in history was. I knew it was a trick question, one to which most people give the knee-jerk response “Adolf Hitler,” “Mao,” or “Stalin.” All of these men murdered millions of their own countrymen, and their death rampages didn’t come to an end until they died (Mao and Stalin) or were forcibly stopped (Hitler).

“Wrong,” said my friend. “The greatest mass murderer in history was Ray Kroc, the founder of McDonald’s.” I got the message. Ruthless dictators use violence. There is no pretense of fun, no clown frolicking on television in an attempt to convince people that happiness awaits them in the gulag.

The fast-food folks, however, while publicly supporting charitable causes aimed at saving the planet and helping the poor, maintain fun-looking killing machines throughout the world — colorful little shacks filled with food weapons that turn people’s bodies into medical time bombs.

Prostate and colon cancer, arteriosclerosis, stroke, and diabetes, while not as spectacular as decapitations and firing squads, succeed year after year in piling up the kind of impressive fatality numbers that would make run-of-the-mill serial killers envious.

In fairness, however, don’t blame the fast-food executioners if you should get killed by a deadly burger, taco, or innocent-looking slice of pizza. These guys are humble. They know full well that they couldn’t do it without their customers’ willingness to delude themselves.

It’s analogous to people getting the government they deserve. While there certainly are exceptions, most people get the health they deserve.

Then there are cigarettes. For more than thirty years, my eldest sister became angry with anyone in our family who urged her to stop smoking. In a spirit of defensiveness, she insisted that she simply enjoyed smoking, notwithstanding the fact that she was a highly intelligent, well-informed individual who certainly was aware of the much-publicized facts regarding cigarette smoke.

Sadly, the day the doctor handed my sister her death warrant — a diagnosis of inoperable lung cancer — she immediately stopped smoking. She spent the rest of her days angry with herself for “being so stupid.” And, of course, she didn’t miss the enjoyment she once got from cigarettes.

If you’ve ever witnessed someone dying of cancer, you know that it’s a pretty grim scene, one you never forget. It certainly makes you think long and hard about your own mortality.

I believe that what allows a person to engage in a dangerous activity with impunity, be it smoking, unhealthy eating, or drunk driving, is the self-delusion that he will be the one to defy the odds and escape the inevitable consequences of his actions. Coming to grips with one’s own mortality requires that an individual override his wishes with reality and guide his actions accordingly.

If truth is the underpinning of rational action, then the first and most critical truth to accept is the reality that you are not immortal. One’s own mortality is another one of those truths that most people accept on an intellectual level but do not believe on a day-to-day, emotional level. The best way to combat this dangerous mind-set is to be vigilant about eliminating any delusions you may be unconsciously harboring about your own mortality.

Ironically, the more you act on the belief that you’re immortal, the sooner you are likely to find out, to your dismay, that you are not. A better idea is to live in accordance with truth and enjoy good health while you’re here. The reason you must be vigilant about this matter is because you will always be surrounded by temptations to eat, drink, and partake in activities that are anti-life. Instant gratification is unlikely to be gratifying enough to offset years of regret.

Trust me on this one: You are mortal. Accept this reality, be protective of your well-being, treat your body with respect, and you may just stick around long enough to enjoy a life worth living.