The outcry with which people greeted ex-planet Pluto’s change in status took Archimedes by surprise. Even the language used was astonishing. Pluto had been “demoted”, “banished” and “stripped of its status”. The Age newspaper wrote an editorial on the topic, and the Times of India reported people buying bumper stickers over the Internet asking fellow drivers to “Honk if Pluto is still a planet”.
Bizarre! Nothing had changed physically—only the words used to describe Pluto’s position in the Solar System. The fact is that it always was different from the eight other planets with which it was formerly lumped—tiny (smaller than the moon), surrounded by debris, and with an orbit which intersects with Neptune outside the planetary plane. So now we’re recognising the fact.
What has changed is a thought pattern in people’s minds. All that time devoted to learning about Pluto as a planet, and the mnemonic to remember the nine (now eight) planets in order. What right have scientists to change their minds, people have demanded. What right to admit that they didn’t have it quite right the first time? How dare they rob us of a childhood verity?
It’s an illustration of a wider problem for science itself, and a general misunderstanding of the way it works. The misunderstanding is partly the fault of scientists themselves, and partly fostered by those who find scientific evidence at odds with their beliefs.
You see, many scientists like to portray what they find as 'reality' or 'the truth'—and their craft certainly does provide a model of reality. But that’s just what it is, a model. Furthermore, this introduces another great strength of science—it is self-correcting. It can provide better and closer models to reality as it accumulates more evidence. In the process some of the old ideas of reality or the truth are swept away, which jolts people's faith and upsets their sensibilities.
In fact, the ground always has the potential to shift, and that worries many people, who like certainty. When Archimedes was a student of zoology, the revolution of molecular biology was in its infancy. The sophisticated techniques which allow researchers to study the stuff of life, DNA, were being developed, and genes began to be studied as chemical entities.
The upshot was that the process and progress of evolution and the origin of species was opened to scrutiny at a level never possible before. Suddenly, we could see evolution happening before our very