Sunday, September 12, 2004

The mystery of life? I don't know.

Albert Einstein said, "Theories should be as simple as possible, but no simpler."

At first glance, this may sound like a Zen koan, or a paradox. In fact, it is a profound statement that says more than volumes of philosophy.

But first, a bit of background.

From the dawn of time, people have resisted saying "I don't know." They looked instead for explanations in tribal tradition, sacred books, or the supposed wisdom of shamans, priests and prophets.

The most common cover-up for ignorance is to invoke divinity. A storm that devastates a village is "an act of God." A child taken by disease at a young age is divine punishment for a parent's sin. And so on.

Superstitions too have their origin as a cover for ignorance. I lost my wallet because a black cat crossed my path. My lover left me because Venus was in the wrong house of the zodiac. I won at the roulette table because I was holding my lucky rabbit's foot.

In every case a reluctance to say, "I don't know." No admission that the cause of an event might be unknown or unknowable.

Traditionally, people have divided explanations into true and false. In general, truth is what we believe. Falsehood is what everyone else believes, if different.

Einstein's remark suggests another attitude towards knowledge.

On the one hand, we have reliable theories, characterized by the simplicity with which they explain experience. Not absolute truths, but provisional truths that work well for the time being and are open to revision.

For example, Newton's theory of gravity qualifies as reliable knowledge because of the way a few simple equations explain everything from the motion of planets, to the fall of an apple, to the flow of the tides. With Newton's equations we can predict the return of a comet -- Halley's Comet, say -- to the day, hour, second, hundreds of years in advance. That's reliable knowledge.

The theory of evolution by natural selection explains with almost self-evident simplicity the diversity and interrelatedness of life on Earth as revealed in the fossil record and in the genes. That's reliable knowledge.

That's knowledge as simple as we can make it.

Beyond that, according to Einstein, we must be humble enough to say "I don't know."

Those three little words, "I don't know," are completely modern. They are the essence of the scientific way of knowing, and they set the person of scientific temperament apart from every other people who have gone before -- and from most people who are alive today.

Beneath reliable knowledge Einstein draws a line. Don't suppose we know what we don't know, he suggests. Don't make up fictions -- gods, spirits, superstitions, the influence of the stars, lucky charms -- to explain things for which we have as yet no reliable explanation.

As simple as possible, but not simpler.

The physician/essayist Lewis Thomas wrote : "The greatest of all the accomplishments of 20th-century science has been the discovery of human ignorance." He was talking about the recognition that there is an entire universe below Einstein's bottom line about which we know nothing, and about which we should be willing to admit that we know nothing.

Those three little words -- "I don't know" -- are used far too infrequently by teachers, politicians, religious leaders, even philosophers. With the presumption of knowledge where no reliable knowledge exists goes righteousness. Righteousness breeds pogroms, jihads and crusades. Righteousness flies airplanes into skyscrapers and holds children hostage in schools. Righteousness presumes to forcibly impose on others what we think they want or need.

If science has given one great gift to the world -- greater than the wonders of technology, greater than modern medicine, greater than flights to the moon and planets -- it has given us permission to say "I don't know."

How did life evolve from non-life? I don't know. What is consciousness? I don't know. What started the big bang? I don't know. Why did my father die at a relatively young age of cancer? I don't know. Why do bad things happen to good people? I don't know.

As simple as possible, but no simpler. Ironically, it is when we give up thinking we know it all that we begin to acquire reliable knowledge.

When we think we know everything, thinking stops.

Further Reading

For more on the discovery of ignorance and the response to mystery, see my Climbing Brandon: Science and Faith on Ireland's Holy Mountain, now also available in Ireland and the UK.

Student Activities

Write the following list of words on the board. You may want to add other terms in the same spirit. Ask for a show of hands for how many in the class can provide a reasonable definition of each term.

PCR (polymerase chain reaction). ESP. SETI. Yeti. Gigahertz. UFO. Cosmic microwave background radiation. Hot (and cold) fusion. Reincarnation. Loch Ness Monster. Pulsar. Shroud of Turin. Fractals. Close encounters of the third kind. Human genome. Bermuda Triangle. Adam and Eve. Superconductivity. Electron microscope. Horoscope.

I predict that far more hands will go up for those things that reside below Einstein's bottom line, than for those he would consider reliable knowledge. Discuss.

Discuss this essay and more over on the Science Musings Blog.