At the huge and overwhelming show entitled Galileo: Images of the Universe from Antiquity to the Telescope, continuing at the Palazzo Strozzi in Florence until August 30, two small exhibits stand out among all the elaborate paraphernalia of astrolabes and orreries. These are the great scientist’s telescope, hardly bigger than a fold-up umbrella, and the very beautiful watercolour sketches that Galileo, with the help of his telescope, made of the moon in various phases from Padua in November and December 1609, almost exactly 400 years ago.

What struck me most was the sheer modesty of these momentous objects. Galileo’s telescope looks no bigger or more powerful than the kind of instrument one might give nowadays to an eight-year-old child. In fact, inspired both by children’s toy telescopes and the spy glass patented by Lipperhey, Galileo set about grinding and polishing his own lenses until he had an instrument capable of magnifying 20 times, as opposed to four or six. The use he made of it is shown by the exquisite and inspired watercolour sketches, which cross the boundaries erected since Galileo’s time between the worlds of art and science.

Galileo is rightly held up as one of the great champions of empirical science, prising the study of nature out of the dead grip of religious authority, oppressed by the blind dogmatism of the Catholic church and the Inquisition, which forbade him to express his support for the Copernican system, and forced him, at least in public, to recant the Copernican conclusions of his Dialogue Concerning the Two Chief World Systems of 1632. Even after his recantation, under house arrest, Galileo continued to exercise his vocation as a free thinker, reasoner and observer.

The little telescope is a wonderful symbol of all this. Of course the technical achievement is impressive, especially as it was done by an amateur. But even more impressive than the technique was the attitude. What was necessary, as well as the ingenious piece of equipment, was the courage to guess that the dogma of centuries might be half-baked – that all the solemn authorities of the past and present had got it wrong, not just slightly wrong but completely back to front.

It did not take Galileo long – a few cold nights of that Paduan winter – to establish that the Aristotelian-Ptolemaic view of the moon, held for centuries, was false. The moon was not a perfect sphere, nor was it smooth, but pockmarked with craters and crested with mountain ranges. And all that was merely the beginning. Galileo also observed the moons of Jupiter, the phases of Venus, and sunspots, gathering evidence to show irrefutably that the earth and other planets orbited the sun. He was a Copernican before he picked up the telescope, but the telescope confirmed what he had already surmised.

All this was achieved, let us remember once again, with an instrument you could hide in the pocket of a long coat. Since Galileo’s time telescopes have increased in size and power beyond the imagination of the Pisan astronomer. We now have the great radio telescopes and the Hubble space telescope, capable of reaching forward, or back, into dizzying expanses of space and time.

But has the wisdom of scientists and astronomers increased with the power of their instruments? This was in part the question Berthold Brecht pondered when he set about revising his play The Life of Galileo in the light of the nuclear bombs dropped on Hiroshima and Nagasaki. When he first drafted the play, Brecht saw Galileo as a canny, cunning role model for scientists and thinkers oppressed by the Nazis. Recant in public and continue working in private was the idea. But in August 1945 he saw the disastrous selling-out of science to power, and fingered Galileo as the great betrayer.

Whatever you conclude, I can’t help thinking that there is something too modern and unGalilean about Brecht’s Galileo. If you go back to the simplicity of the telescope and the words Galileo wrote in the Dialogue Concerning the Two Chief World Systems, you find a different perspective. For someone who with Newton and Darwin did more than anyone to change our view of the natural world, Galileo was startlingly modest about his own achievement and about science in general.

“There is not a single effect in nature, even the least that exists, such that the most ingenious theorist can arrive at a complete understanding of it,” says Sagredo in the Dialogue. “For anyone who had experienced just once the perfect understanding of one single thing and had truly tasted how knowledge is accomplished would recognise that of the infinity of other truths he understands nothing.”

For Galileo, it seems, gazing into the night sky in Padua through that little leather cylinder bounded by homemade lenses, the uncovering of a few of nature’s mysteries prompted a humble acknowledgement of the vast extent of the unknown.

harry.eyres@ft.com
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