When politicians change their minds, they're often lambasted for flip-flopping by other politicians, the media and the public. When scientists change their minds, their fellow scientists eventually see it as progress, integral to the self-correcting discipline of their vocation.
Unfortunately the public usually notices only a marginal subset of this phenomenon: how the futurists and short-term forecasters so often get it wrong.
After all, where is the paperless office? Or the Jetsons' flying car? And remember how hurricane forecasters used computer models to predict – wrongly – that the last two seasons would be monsters?
For a spectacularly bad computer projection, look at the mid-1970s, when a study from the Club of Rome warned that the world would run out of many essential minerals before the end of the century. Skeptical researchers picked apart the naïve assumptions of "The Limits to Growth," but not before world leaders, including Pierre Elliott Trudeau, had jetted off to an Austrian castle for a summit.
Yet the truly important self-corrections of science often escape public attention because they escape the media's attention. That's mainly because journalism exists on the time scale of mayflies while scientific consensus evolves over elephantine decades.
A personal example: When I was squeaking through university science in the mid-1960s, we were taught that the adult brain does not make new neurons.
But even then, unbeknown to us, a few researchers were arguing that the adult brain did continue to manufacture neurons. But they were dismissed as crackpots, just as Alfred Wegener was in 1915 when he proposed that the continents drifted. Or as Mario Molina and F. Sherwood Rowland were in 1974 when they warned that CFCs were destroying the ozone layer.
Molina and Rowland were vindicated in just a few years and went on to win the Nobel Prize in chemistry. But it wasn't until the 1950s that continental drift was accepted as the consensus theory.
The neuron "crackpots" were finally declared correct by their fellow brain scientists in the 1990s, and today adult neurogenesis – the fancy name for making new neurons – is a burgeoning field of study for people such as Stanford neuroscientist Robert Sapolsky, who originally dismissed the idea.
Sapolsky is one of 130-plus scientists and "thinkers" who have contributed highly personal revelations to What Have You Changed Your Mind About?, due next month.
Book marketing seems to demand sensational subtitles, but Today's Leading Minds Rethink Everything turns out to be an accurate guide to the content. In almost 400 pages, the contributors cover frontier aspects of all three scientific arenas: physical, biomedical and social.
It should come with a warning: "Reading this book may be dangerous to your cherished myths and perceptions." For example:
- Helena Cronin says it's not primarily bias and barriers that give men the top positions and prizes. After analyzing the statistical evidence, the philosopher at the London School of Economics has come to accept that there will be (as she puts it) more dumbbells and more Nobels among males because there's a much greater variance in ability among men as a group than among women, even though both are similar on average.
- There is probably no intelligent life elsewhere in the universe because we would have detected a stray electromagnetic signal by now, argues technologist Ray Kurzweil, who wanted to believe in E.T.
- Until a few years ago, neuroscientist Joseph LeDoux thought that a memory is something stored in the brain into which we could tap again and again. Then a researcher in his lab at New York University did an experiment that convinced LeDoux – and is convincing others – that each time a memory is used, it has to be stored again in the brain as a new memory to be accessible later. This concept of memory "reconsolidation" is now being tested in treating drug addiction and post-traumatic stress disorder.
- Danish science writer Tor Nørretranders changed his mind about his body, which he now considers closer to software than hardware. It's been known for decades that 98 per cent of the atoms in the human body are replaced every year, but only recently was Nørretranders able to come up with the concept of permanent reincarnation, like music moving from vinyl LPs to audio tapes to CDs and now iPods.
Many other contributors challenge conventional wisdom to write about, among other things, a finite universe; the brain creating a soul; and the Internet as a powerful tool for centralized state control.
Nor do all these deep thinkers agree. Computer scientist Rudy Rucker has come around to thinking that a computer program will be able to emulate the human mind so that self-aware robots could even believe in God. But computer scientist Roger Schank, who once said he would see machines as smart as humans within his lifetime, now believes that won't happen within the lifetime of his grandchildren.
The book's most important contribution, however, is to drive home the lesson that in science being wrong occasionally is a good thing, not least because it renews curiosity and reminds the scientists that they don't know everything.
As Discover magazine columnist Jaron Lanier writes in the book, "Being aware of being wrong once in a while keeps you young."
And since admitting they've been wrong and changing their minds works well for rational decision-making by scientists, perhaps politicians, the media and others might give it a try.