2015-02-26 – I have a Facebook friend who seems to be an anti-vaxxer. Maybe he is and maybe he isn’t. You can’t always tell from Facebook. My Facebook friend is maybe 20 years younger than I am. I also know his father who is maybe 10 years older than I am.

The age differences are important.

I was part of the first generation to get a course of vaccines. I remember the first polio vaccines, which I had, along with smallpox, diphtheria, tetanus, and whooping cough. There was no vaccine for measles, mumps, rubella, or chicken pox. We got those diseases. If we were lucky, we got better. I owe my nearsightedness to measles. I owe my current case of shingles to the chicken pox I had in eighth grade. (I was planning to get the vaccine, but didn’t act fast enough.) Vaccines for herpes and shmerpes came along much later. My sons had them.

My Facebook friend never saw these diseases. He never saw the fear of a parent who thought their child might have polio. I did. I was the kid—fortunately what I had wasn’t polio. My Facebook friend’s father saw even more of this.

So the risks of being unvaccinated are unreal to my Facebook friend. Vaccines, of course, have risks—real risks. Those risks seem really dire if you’ve never seen the diseases we routinely escape—because we are vaccinated. It makes you mad to think that pharmaceutical companies are exposing us to risk—if you don’t know about the risk that vaccines hold at bay in the way your father knew about those risks.

Now, I’m not writing about vaccines today. I’ve done that before (here’s the latest). That’s enough. What I want to talk about today is the way people act when risks go away. It leaves a kind of void when you expect to be battling for your life and . . . well, you’re not.

A few years ago, cognitive scientist Steven Pinker wrote a book called The Better Angels of Our Nature: Why Violence Has Declined. The gist of the story is that over, the sweep of human history, violence has decline. Wars kill fewer people than they once did. Violent crime has declined. The decline is not a straight line. Violence has its ups and downs—just like the stock market. But the overall trend is down.

A recent article in the Atlantic, called Be Not Afraid, says that people have a hard time believing that. They see the news from the Middle East or Ukraine or North Korea and say that we live at the most dangerous time in history.

But it’s not true. I bet that, if you take a few breaths and calm down, you might be able to list a few things from history that were far worse—even if you don’t know much history. And so we obsess about minor risks that in pre-modern times people would have considered part of paradise.

It’s like we’re programmed to fight—even when there is little or nothing to fight against.

Sure, there are still bad things. Wars still happen. People still get sick. We have plenty of wealth, but some folks hoard it. But these risks are orders of magnitude less than what people had to live with even a century ago. Life expectancies have nearly doubled in that time. In 1918 somewhere between 20 and 40 million people died of the flu—more than died in World War I. Today, there’s a vaccine for that—though it is far from perfect. Today, we get hysterical about two cases of Ebola in the United States and a few thousand worldwide.

I guess, if you don’t have a big problem, you have to worry and get mad about something. (Just people don’t let your worrying bring back the bad old days.)