Say you are walking down the street and you find a $20 bill. You didn’t see anyone drop it and there is no obvious place where you could leave it for its rightful owner, so now it’s yours.

How do you feel?

That’s an easy one, right? Here’s another. The latest new beer has been released at your favorite microbrewery. When you finally get to the head of the line, you pull out your wallet and the $20 bill that you thought was in there is gone. Somehow you’ve lost it.

Now how do you feel?

These are not trick questions. Everybody feels good about finding a $20, and everybody feels bad about losing one, even if they don’t like beer. But which feeling is more significant?

Would you be happier about finding a bill than you would feel sad about losing one? Or would you feel worse about losing money than you would feel good about finding some?

If you are like most people, it’s the latter. The bill is worth just as much either way, but emotionally we hate losing more than we like winning, according to work of psychologist Daniel Kahneman, who won the 2002 Nobel Prize in economics. It’s a phenomenon he calls “loss aversion” and something that he felt was not taken into account in standard economic models, which assume everyone is a rational actor who would put the same value on a $20 bill, whether it was coming or going.

Here’s another example. Consider two plays at first base: In one, Doug Mientkiewicz records the last out in the 2004 World Series giving the Red Sox their first championship in 86 years; in the other, a grounder bounces through Bill Buckner’s legs, costing the Red Sox the game and the 1986 World Series.

For a Red Sox fan, which one matters more? Kahneman would say it’s Buckner, not Mientkiewicz. Even Mientkiewicz would probably agree.

I ran into Kahneman’s study in a book on behavioral modification called “Thinking Small: The Surprisingly Simple Way to Reach Big Goals,” by Owain Service and Rory Gallagher, two British psychologists who ran their government’s Behavioral Insights Team, using the latest research to help nudge people into making better choices, like quitting smoking or paying their taxes on time (it was informally known as the “Nudge Unit”).

The study came up in a discussion about how to set up reward systems to best motivate yourself or others, but it also explains a lot of what goes on in American politics.

We overvalue the status quo and we hate to lose. We will make irrational judgments on that basis. The obvious political example is the resilient support Donald Trump enjoys in some circles, despite a brutal five months in office.

He has failed to deliver on every item on his domestic agenda. He has cozied up to dictators, insulted allies and sits in the middle of an international election-tampering scandal that makes Watergate look like, well, like a third-rate burglary. Yet he still has an 87 percent approval rating among Republicans.

You have to wonder if there is anything he could say or do to make those Trump voters say, “Oops.” But it’s not just an issue for conservatives, or Trump Republicans.

How many “progressive” policy ideas have anything to do with “progress”? For every Bernie Sanders-style proposal to expand education or health care, there are dozens of defensive measures designed to hold on to what we’ve already got.

The demonstrations to save Obamacare are much more passionate than the celebrations were when it passed.

On the local level, a progressive cause is much more likely to be about stopping a development or a zoning amendment than it is about building something new.

Which do you think would be more successful: A fundraising letter from an environmental group that said, “the environment is pretty good, but we’d like to make it better” or one that says, “Trump and LePage want to take away the protections that keep our air and water clean”?

It’s the second one, of course. This is how we are wired, and it’s no secret.

Advertisers and political consultants have known about our status quo bias and loss aversion for a long time (Kahneman’s paper was published in 1991). But most of us still think of ourselves as rational actors weighing all the evidence and making wise choices.

But we’re not, at least not all the time. And as long as we can convince ourselves that one $20 bill is worth more than another, we’re going to be easy to fool.

Listen to Press Herald podcasts at www.pressherald.com/podcast.

Greg Kesich is the editorial page editor. He can be contacted at:

gkesich@pressherald.com

Twitter: @gregkesich