In science, the problem with "unassailable truths" is they can always be assailed.

And last week, a young woman with sunken eyes and hands big enough to palm a beach ball did some "truth assailing."

Her name is Ardi. She was 4 feet tall, weighed 110 pounds and lived 4.4 million years ago.

According to anthropologists, Ardi "reverses the common wisdom of human evolution." Rather than human beings evolving from chimps, it now looks like chimps and humans both evolved from a "humanoid" ancestor — with the humans ending up in charge of the earth and chimps ending up flinging poop around their cages.

The lesson, I think, is easy to spot.

Science needs to stay loose. When new information comes along, it has to adapt.

Science can't afford to get locked into a way of thinking.

But more than science, I think there's a lesson in there for all of us: When you become married to one way of seeing things, it's difficult to grow and learn.

A Chinese proverb says:

The foolish person will reject what he sees,

but never what he thinks.

The wise person will reject what he thinks,

but not what he sees.

Setting your ideas in concrete is never a good idea.

Years ago, I had a boss who would take your measure the first day. If he didn't like you, you were in his dog house. It didn't matter what you did later, when your face came into his mind, it had "loser" written on it.

I think it cost him dearly.

I once asked songwriter Julie De Azevedo about her song "Out of Jail." In the song, she says she's kept someone locked up far too long. It was time to set them free.

"Who's that song about?" I asked.

"All kinds of people," she said.

She was tearing down the dog house.

Locking ourselves into an opinion about people, politics or religion makes it easier to steer ourselves through the world. We don't have to keep re-evaluating things. If people and ideas are never allowed to change, we never have to change. But putting people "in jail" in our minds simply locks us up, not them.

As a buddy once said, "It would be easier for some people to change their hat size than change their point of view."

Too many people read books or listen to things that simply confirm their biases, C.S. Lewis said. They should seek out books and programs that challenge their biases. It can be painful, but those pains will be growing pains.

I think of the bumper sticker: "The truth will make you free — but first it will tick you off."

And today, I'm sure the discovery of "Ardi" has ticked some folks off. She has everyone scrambling now, rethinking what they think, re-seeing what they see. Years of ideas and "unassailable truths" will have to be scrapped.

And that's never a bad thing for science to do.

Just as it's never a bad thing for us to do.

Just be prepared to get ticked off.

e-mail: jerjohn@desnews.com