The following is an excerpt from the keynote address given at the Commencement, University at California at Berkeley.

I want to focus on one reason why the graduates here are unique and special, and suggest a way that they might change the world. Your graduate has joined a tiny percentage of Americans who are scientifically literate. He or she has become part of that 2-3 percent of Americans who understand the process of science-how it works, how science is done and applied.

So what? Is it important that people be scientifically literate? You bet! The late Carl Sagan said it well in his 1996 book The Demon-Haunted World: Science as a Candle in the Dark. In that book, Carl said:

 "We've arranged a global civilization in which most critical elements profoundly depend on science and technology. We have also arranged things so that almost no one understands science and technology. This is a prescription for disaster."

Let me show you why. The vast majority of Americans do not understand how science works and few understand basic scientific facts. The National Research Council (NRC) questioned a random sample of Americans with ten science questions. Here are a few of the questions.

1. How long does it take Earth to go around the Sun? One day, week, month or year? Only 47% knew it took a year, and about 25% thought that the Sun went around the Earth!

2. All radioactivity is man-made. 72% agreed but you know that's wrong.

3. Humans lived with dinosaurs, and I don't mean birds, I mean T. rex. 48% of Americans agreed, and every single one of you graduates know it is wrong. Interestingly, that percentage is identical to what newspaper editors believe! And they control our news.

4. Earth's core is very hot. 78% agreed. As a geologist, I was especially happy about this, because I thought we must be doing a good job teaching about the Earth's structure. I said so at a talk on this same literacy topic at UCLA to over 1,000 people. At the end, someone stood up and said, "Jere, the reason that so many people agree with that is because that is where they think Hell is!"

We are, critically dependent in our daily lives on science, yet hardly anyone knows how it works. I'd point out that in the U.S. Congress, the rate is probably even lower. After all, most of them are lawyers. This general condition may well be at the root of numerous problems in the world.

Perhaps this illiteracy is the reason that so many people believe in paranormal and pseudoscientific claims, at their peril. For example, 60 percent of Americans believe that alien spacecraft visit Earth. While that is silly, why do we spend $29 billion per year on standard medicine and another almost equal amount ($27 billion) on alternative medicines that cannot be demonstrated scientifically to be effective? Why do people pay outrageous sums of money for weird solutions to their problems?

Why aren't more people literate and interested in science? After all, we spend somewhere near $3 billion per year in K-12 science education across this nation alone. To produce what? A population that is 98 percent scientifically illiterate. As Carl Sagan, Paul Ehrlich, and some of us up here have said, that is simply not good enough.

At some point people lose interest in science, and all of that money goes down the drain. While there are many reasons, the media is an obvious culprit. Look at the huge number of pseudoscientific programs on television, presented as documentaries, news, dramas, and sitcoms. One network recently showed the particularly antiscientific programs "Mysterious Origins of Man" and "Aliens Among Us," and other such programs. Their alien program was presented as if it were a true scientific investigation, but it was not the news division that produced it, it was the entertainment division! Thus, truth is confused with fiction, reality with fantasy, and authorities with charlatans. Few people can tell the difference because they simply do not have the tools to do it.

Be careful with the media, graduates! It's usually a far cry from the way things really are, especially on TV. Be a skeptical reader and be a skeptical viewer!

The general public sees science as difficult, boring, and often useless. But let me show you a different view. Our graduates know this already. Science is fun; science is creative; science is so satisfying. It's a good life.

Scientific literacy provides far more than knowledge and a way to view the world. It provides enjoyment of life as well. So what is scientific literacy? It is basically three things mixed with an assortment of facts: It is critical thinking, evidential reasoning, and evaluation of authority plus whatever scientific facts you think are particularly important.

Critical thinking involves eight skills, the most important of which are to avoid emotional thinking, determine biases, consider other interpretations, and, perhaps, the most important, tolerate uncertainty.

Evidential reasoning includes six rules. Any claim must be falsifiable in theory, the argument must be logical, it must be comprehensive, honest, and the evidence must be replicable. Most importantly here, it must be sufficient. In other words, extraordinary claims demand extraordinary evidence. Don't be fooled by the person who claims to have an alien in his garage when he shows you a blurry picture. Demand that he show you an arm, leg, head, or DNA from his alien, if it has any. Similarly, demand evidence from your doctor, auto repairman, insurance man, Realtor, teacher or whoever, that their claims are underpinned by sufficient evidence to support their claims.

Lastly, question authorities. Do the authorities practice critical thinking and evidential reasoning? If not, don't believe them. Do they have the proper credentials? If not, don't believe them. Do they have appropriate employment? If not, question them.

If you do these things, your lives will be happier, just like the people up here and the students down there, and your checkbook will be fuller. You will vote more wisely, you will decide more sensibly about your own lives, and you will live more comfortably with your surroundings. And especially, you will likely get and keep excellent jobs that you actually enjoy. Our graduates have a significant advantage over most other Americans because they are scientifically literate.

And I hope that at least a few of you graduates will take my words here to heart and think hard about how to improve scientific literacy in America. You have the tools to change our world, just like other past Berkeley graduates. Our nation deserves it, and you deserve it. Do not let Carl Sagan's "prescription for disaster" come true! Change the world. You can do it.

Author: Jere H. Lipps is in the Department of Integrative Biology, University of California, Berkeley.