argued against the doctrine of the Roman Catholic Church
has been rediscovered in London.
Credit: The Royal Society
that the astronomer toned down the claims
that triggered science history's
most infamous battle...
...then lied about
The original letter - long thought lost - in which Galileo Galilei first set down his arguments against the church's doctrine that 'the Sun orbits the Earth' has been discovered in a misdated library catalogue in London.
Its unearthing and
analysis expose critical new details about the saga that led to the
astronomer's condemnation for 'heresy' in 1633.
But because the original
letter was assumed to be lost, it wasn't clear whether incensed
clergymen had doctored the letter to strengthen their case for
heresy - something Galileo complained about to friends - or whether
Galileo wrote the strong version, then decided to soften his own
The newly unearthed
letter is dotted with scorings-out and amendments - and handwriting
analysis suggests that Galileo wrote it. He shared a copy of this
softened version with a friend, claiming it was his original, and
urged him to send it to
It was rediscovered in the library there by Salvatore Ricciardo, a postdoctoral science historian at the University of Bergamo in Italy, who visited on 2 August for a different purpose, and then browsed the online catalogue.
Ricciardo, together with his supervisor Franco Giudice at the University of Bergamo and science historian Michele Camerota of the University of Cagliari, describe the letter's details and implications in an article in press at the Royal Society journal Notes and Records.
Some science historians declined to comment on the finding before they had scrutinized the article.
But Allan Chapman, a science historian at the University of Oxford, UK, and president of the Society for the History of Astronomy, says
to his friend Benedetto Castelli.
The last page shows his signature, "G. G.".
The Royal Society
Most crucially, he
reasoned that the heliocentric model of Earth orbiting the Sun,
proposed by Polish astronomer
Nicolaus Copernicus 70 years
earlier, is not actually incompatible with the Bible.
Historians know that Castelli then returned Galileo's 1613 letter to him, and that on 16 February 1615 Galileo wrote to his friend Pietro Dini, a cleric in Rome, suggesting that the version Lorini had sent to the Inquisition might have been doctored.
Galileo enclosed with
that letter a less inflammatory version of the document, which he
said was the correct one, and asked Dini to pass it on to Vatican
were deemed heretical
and he lived his final nine years
under house arrest.
The changes are telling.
In one case, Galileo referred to certain propositions in the Bible as,
He crossed through the word "false", and replaced it with "look different from the truth".
In another section, he changed his reference to the Scriptures,
This suggests that Galileo moderated his own text, says Giudice.
To be certain that the
letter really was written in Galileo's hand, the three researchers
compared individual words in it with similar words in other works
written by Galileo around the same time.
When his one day at the
Royal Society was finished, he idly flicked through the online
catalogue looking for anything to do with Castelli, whose writings
he had recently finished editing.
According to the catalogue, it was dated 21 October 1613.
When Ricciardo examined it, his heart leapt. It appeared to include Galileo's own signature, "G.G."; was actually dated 21 December 1613, and contained many crossings out.
He immediately realized the letter's potential importance and asked for permission to photograph all seven pages.
The misdating might be one reason that the letter has been overlooked by Galileo scholars, says Giudice.
The letter was included
in an 1840 Royal Society catalogue - but was also misdated
there, as 21 December 1618. Another reason might be that the Royal
Society is not the go-to place in the United Kingdom for this type
of historical document, whose more natural home would have been the
They know that it has been there since at least the mid-eighteenth century, and they have found hints in old catalogues that it might even have been there a century or more earlier.
The researchers speculate
that it might have arrived at the society thanks to close
connections between the Royal Society and the
Academy of Experiments in
Florence, which was founded in 1657 by Galileo's students but
fizzled out within a decade or so.