You get a few years under your belt, you develop a few pet theories about how to live your life. One of my favorites concerns the avoidance of what I call “optional danger.” 

It’s a simple construct: Life is a fairly dangerous proposition, given that none of us gets out alive. So I avoid taking death-defying risks on purpose. 

I don’t bungee jump, hang glide or heli ski. Nor will I ever parachute out of a perfectly functioning airplane for kicks. And I do my best to keep it to about 85 miles an hour on wide-open freeways in broad daylight (Note: This newspaper does not advocate breaking the law. Your results may vary).

I’m not a fanatic about the optional danger thing — I drink Diet Coke, which can’t be good for me, and I used to own a motorcycle — but I tend to stick with it as a general rule. 

That’s why I made an appointment to head to CVS for a COVID-19 booster vaccination this week. The rationale? The first two Pfizer shots seemed to work well. I had no side effects. And to my knowledge, I haven’t gotten COVID-19 yet. I’m eligible for the shot because I have asthma and it’s free, so why not?

My guess: About 20% of you reading this at home are saying, “Because you’re an idiot, that’s why not.”

I’m basing this estimate on the multiple polls I’ve read about Americans’ willingness to get vaccinated at this point in the pandemic.

The breakdown: About 7 in 10 of us have gotten at least one shot. Another 8% say they plan to get it. About 2% say they’re still not sure. And the remaining 20% say, “Hell no, over my dead body.”

I have quite a few friends who haven’t been vaccinated, and we’ve talked it through. While a few view the decision as a way of asserting their freedom, most explain their choice with a riff on my optional danger theory.

Except for them, the risk in question isn’t COVID-19; it’s what’s in the vaccine.

One friend explained it like so: “Of course I trust science. But there’s never been a study of the long-term effects of this vaccine. So who knows what it’s going to do to you in 10 years? I’m pretty young and I’m in good health, no immune issues. The chances of COVID killing me are slim. So why risk it?”

I can understand his logic. Last year, COVID-19 killed about 370,000 Americans. So far this year, it’s been blamed for another 325,000 deaths. That’s about two-tenths of a percentage point of the total U.S. population. 

In contrast, heart disease kills about 660,000 people a year nationwide. Even so, McDonald’s sold $40 billion worth of artery-clogging crap in the United States last year. 

For me, the optional danger of dying in a pandemic outweighs the risk of the vaccine. At the same time, I went to a concert — sans mask — with 15,000 fellow fans of the Eagles last week. 

As it turned out, the band required each attendee to produce proof of vaccination at the gate, which created a lot of drama in line at the arena downtown.

When I told my unvaccinated buddy about the requirement, he was offended. I get it — no one likes to be singled out. But for me, it’s like the Eagles hit says: I get a peaceful, easy feeling whenever I avoid optional danger.