Burned Alive: Bruno, Galileo and the Inquisition Read online

  B U R N E D A L I V E

  alberto a. m artínez

  BURNED ALIVE

  giordano bruno,

  galileo and

  the inquisition

  reaktion books

  Published by

  reaktion books ltd

  Unit 32, Waterside

  44–48 Wharf Road

  London n1 7ux, uk

  www.reaktionbooks.co.uk

  First published 2018

  Copyright © Alberto A. Martínez 2018

  All rights reserved

  No part of this publication may be reproduced, stored in a retrieval system,

  or transmitted, in any form or by any means, electronic, mechanical,

  photocopying, recording or otherwise, without the prior permission

  of the publishers

  Printed and bound in Great Britain

  by TJ International, Padstow, Cornwall

  A catalogue record for this book is available from the British Library

  isbn 978 1 78023 896 8

  CONTENTS

  Introduction 7

  1 The Crimes of Giordano Bruno 14

  Pythagoras and Copernicus 17 | The Moving Earth and the

  Fugitive Friar 28 | Prisoner of the Inquisition 37 | Censured

  Propositions in Bruno’s Books 47 | Fire and Smoke 70 | Why

  the Romans Killed Bruno 77

  2 Aliens on the Moon? 100

  Kepler Announces Life in Other Worlds! 103 | Campanella

  Imprisoned and Tortured 115 | Bellarmine and the Enemies

  of Bruno 123 | Galileo in Danger 137

  3 The Enemies of Galileo 161

  Campanella Defends Galileo from Prison 171 | Galileo Defends

  the Pythagorean Doctrines Again 179 | Inchofer Against the

  New Pythagoreans 203 | No Life in Other Worlds, No Living

  Earth 211 | Campanella’s Exile and Death 232

  4 Worlds on the Moon and the Stars 238

  How Heretical, Really? 239 | Bellarmine’s Innumerable Suns 247

  Critiques after Galileo’s Death 251 | Conclusion 264

  references 281

  acknowledgements 329

  photo acknowledgements 333

  index 335

  Men of Galilee, why do you stand gazing up at the sky?

  Acts 1:11

  I have indeed asserted infinite particular worlds similar to the

  Earth, which with Pythagoras I consider a star, similar

  to which is the Moon, other planets and other stars,

  which are infinitely many.

  Giordano Bruno to the Inquisition in Venice, 1592

  INTRODUCTION

  Most people know about Galileo. They know that he said

  the Earth moves around the Sun. And they know that he

  got in trouble with the Catholic Church for doing so. The

  Roman Catholic Inquisition condemned old Galileo to surrender

  his freedom for the rest of his life. Nowadays he is admired as a hero

  in the history of science.

  Fewer people know about Giordano Bruno. Years before Galileo,

  Bruno too was put on trial by the Inquisitors. They imprisoned him

  for almost eight years. Then they finally condemned him to what

  was feared as the worst kind of punishment: the jailors gagged him,

  tied him to a post in a public place in Rome, and set the pyre on fire

  to broil and burn him alive.

  Historians say that Giordano Bruno was not condemned for

  his beliefs about astronomy or cosmology – unlike Galileo. Still,

  Bruno is increasingly famous. He was featured in the remake of the

  popular tv series Cosmos. Its first episode, which dedicated much

  of its airtime to Giordano Bruno, aired in 2014 and was watched

  by roughly seven million people in the u.s. The narrator, the astrophysicist Neil DeGrasse Tyson, said that Bruno risked his life by voicing his vision of the cosmos: ‘the penalty for doing so, in his

  world, was the most vicious form of cruel and unusual punishment.’

  Soon, many commentators complained that Cosmos had misrepresented Bruno by echoing the myth that the Inquisition killed him for his cosmological views.

  This book shows, despite all expectations, that Giordano Bruno

  really was burned alive for his beliefs about the universe. Bruno

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  burned alive

  argued that the Earth has a soul and that many worlds exist.

  However, historians didn’t know that those beliefs were con sidered

  heresies, that is, crimes against God, punishable by death. By inspecting books on heresies and Catholic law, I found that these beliefs were heretical long before Bruno advocated them. Bruno didn’t

  know this, and neither did later science writers. Furthermore, this

  book will show that these same censured beliefs were involved in

  the Catholic opposition to Galileo.

  For over a hundred years, people have wondered whether the

  infamous trial of Galileo was connected to the Inquisition’s previous

  trial against Bruno. This book will show that these trials were indeed

  linked. Some of Galileo’s critics were annoyed that he seemed to

  support Bruno’s ‘horrendous’ beliefs: that many worlds exist and that

  the Earth moves because it has a soul.

  Christians denounced such beliefs as ‘Pythagorean’. In ancient

  times Pythagoras was allegedly the Greek author of the theory that

  Earth is one of the stars and that it moves. But historians didn’t

  know that for a thousand years prominent Christians demonized

  Pythagoras and his disciples as deceptive sinners and false imitators

  of Jesus Christ. This book will illuminate the Copernican Revolution

  in that neglected context. Surprisingly, Bruno’s condemnation was

  caused mainly by his obstinate defence of such beliefs: the existence

  of many worlds and the soul of the world. Most importantly, this

  book reveals an unpublished Latin manuscript in which Galileo’s

  most critical judge, the author of the most negative reports used by

  the Inquisition against him, censured Galileo and the Copernicans

  for those same beliefs. The Inquisition condemned the Copernicans

  as a heretical ‘sect’ of New Pythagoreans.

  This story is about the roots of the notorious conflict between

  science and Christianity. Actually, the two have not often opposed

  one another. 1 In fact, Christianity has often sponsored and supported the sciences. But we still struggle to understand what exactly happened between Bruno, Galileo and the Church.

  There is another reason, too, why this story needs to be told: the

  Roman Inquisition won. Not only did it succeed in killing Bruno

  and silencing Galileo, it also succeeded in preventing people from

  knowing Bruno’s beliefs. To this day, more than four hundred years

  after Bruno died, most scientists and teachers are unaware that

  Giordano Bruno’s account of the universe was far more correct than

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  Introduction

  the beliefs of Copernicus, Kepler and Galileo. To this day, scientists

  don’t know that Bruno belongs among those famous men.

  This is because the Inquisition banned and burned Bruno’s

  books. The clergymen of the Index of Forbidden Books pro
hibited

  all Catholics from reading, quoting, discussing or even mentioning any of Bruno’s beliefs. They were forbidden from even writing Bruno’s name. He was a heretic, and Catholics should not write

  about heretics. Thus they buried his role in the history of astronomy

  and cosmology.

  But here’s what really happened. Like Copernicus, Bruno too

  believed and argued that the Earth really does move, at a time

  when hardly anyone else asserted this, and long before Galileo

  and Kepler. Yet Copernicus, Kepler and Galileo wrongly claimed

  that the Sun and the stars do not move. But Bruno rightly said

  that they move. In 1613 Galileo realized that the Sun spins on its

  axis, yet did not realize that it also really moves through space, as

  Bruno expected.

  Copernicus, Kepler and Galileo believed that the Sun is the

  centre of the entire universe. But here too they were wrong. Instead,

  Bruno rightly insisted that the Sun is not the centre, not at all. He

  alone rightly explained that our universe has no centre. Copernicus,

  Kepler and Galileo also believed that the stars were all arranged in

  a spherical heaven, but that was another big mistake. Instead, Bruno

  thoughtfully argued that the stars are distributed homogeneously

  throughout a boundless, infinite space.

  And Copernicus, Kepler and Galileo thought that the Sun is

  not a star. To the contrary, Bruno rightly insisted that the Sun is a

  star, all the stars are suns, and many of them are larger than our Sun.

  He first published these claims in 1584. Only five decades later, in

  1633, did Galileo briefly suggest that the stars are suns – in just one

  phrase in the fictitious voice of one character in his Dialogue of the

  Two Chief Systems of the World.

  Copernicus, Galileo and Kepler mistakenly said that the orbits

  and motions of the planets were circular. But in 1584 Bruno rightly

  denied it, insisting that no heavenly motions are real y circular. Only

  35 years later did Kepler realize and prove that the orbits of planets

  are not really circular. Galileo apparently never agreed with Bruno’s

  or Kepler’s claims that the orbits were not circular. He mistakenly

  argued that all natural motions are circular.

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  burned alive

  Next, in 1584, Bruno rightly anticipated that the Moon has

  mountains and valleys. Copernicus, Kepler and Galileo published

  no such prediction or claim: yet by 1610 Galileo confirmed with his

  telescope that there are mountains and valleys on the Moon.

  In 1584, and frequently thereafter, Bruno claimed that ‘innumerably many stars’ exist, stars never seen before. Copernicus, Kepler and Galileo made no such claim or prediction. By 1610 Galileo, with

  his telescope, detected countless many stars that nobody in human

  history had ever seen. He announced it on the title page of his book

  as the discovery of ‘innumerable stars’.

  Bruno argued that the stars are surrounded by planets that are

  invisible to our eyes. Copernicus and Galileo made no such claim,

  and Kepler even denied it. Yet again Bruno was right: four centuries later, in 1988, astronomers finally detected and confirmed the existence of a planet outside of our solar system. To date they

  have found thousands of planets, just as Bruno expected. They are

  now known as ‘exoplanets’. In May 2016 news articles reported that

  astronomers had recently confirmed the existence of many more

  Earth­sized planets detected with a space telescope. It is ironic that

  this telescope ­spacecraft, designed precisely to detect exoplanets, is

  named Kepler, who actually denied the existence of exoplanets. It

  should have been called the Bruno Telescope.

  Next, Bruno also specified that some planets, other than the

  Earth, are surrounded by moons. Copernicus, Kepler and Galileo

  anticipated no such thing. Yet in 1610 Galileo discovered that,

  indeed, there are moons orbiting Jupiter. Astronomers nowadays

  expect that moons orbit exoplanets too, as Bruno said.

  Furthermore, Bruno argued that planets are made of the same

  elements as the Earth, that effectively they constitute other worlds.

  Astrophysicists now know that indeed the planets are made of the

  same elements as our world, in different proportions. And our spaceships have explored the surface of those worlds. Bruno proposed that heavenly bodies are surrounded by some kinds of atmospheres, like

  the Earth. Again he was right.

  Bruno even anticipated that humans might walk on and live on

  such distant worlds, even on the closest one, our Moon. In contrast,

  Copernicus made no such claim. Then in 1969, human beings travelled to the Moon and walked on it. Only after Bruno’s writings and Galileo’s lunar observations did Galileo consider that indeed some

  10

  Introduction

  sort of living beings might possibly live on the Moon. But he wrote

  very few words about this, and occasionally denied it.

  When Galileo published a book in 1610, revealing his stunning,

  telescopic discoveries – mountains on the Moon, satellites around

  Jupiter and innumerable stars – such evidence did not confirm the

  cosmological theory of Copernicus. Instead it confirmed Bruno’s

  claims about the universe. Kepler pointed this out.

  Bruno made some predictions that haven’t been confirmed. One

  of them, which he made repeatedly, was that many alien beings live

  on heavenly bodies other than the Earth. Today, many astronomers

  and astrobiologists believe that this too is true, but they haven’t

  yet found any clear evidence of such alien beings, despite countless

  astronomic investigations. But when they finally do, they will prove

  once again that Giordano Bruno was right.

  It is no exaggeration to say that we don’t live in the cosy Suncentred universe of Copernicus. We live in the immense universe of Giordano Bruno. Who was this man who was right about so many

  things? Why has he been so neglected and disdained in the history

  of astronomy?

  Scientists and historians who know about Bruno never make

  the kind of accounting above. Instead they simply give Bruno a

  plain dismissal: they say he wasn’t even a scientist. Why do scientists and teachers know so little about him? It is because of the long­lasting consequence of Catholic censorship of Bruno’s works.

  The Inquisition won. This book will discuss why Bruno’s beliefs

  offended the Catholic clergymen so much and how such beliefs

  were echoed later with hesitation by men who now are far more

  famous: Kepler and Galileo.

  But first, I should say a few things about my approach.

  I focused on primary sources. I have also consulted scholarly

  works that have been very helpful, but for brevity I have abstained

  from long discussions of the extensive, valuable literature. Often

  I give quotations from primary sources rather than paraphrase.

  Having studied the evolution of myths in the history of sciences

  and mathematics, I know how much meaning can change by omission or addition of a single word. So wherever I see an interesting paraphrase in a book or article I immediately wonder: what does

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  burned alive

  the original actually say? My preference for quotations reflects that

 
sentiment. In most cases I give my own translations from the originals, mainly from Italian, Latin, Greek, French and Spanish sources.

  Regarding excerpts from poems and songs, I’ve translated each word

  literally rather than retaining rhyme or metre by inventing phrases.

  Writers make fascinating portrayals of the past, coloured by conjectures. However, I also appreciate the modest approach in which writers take great efforts to convey the past plainly, to say clearly

  what happened, while trying not to get in the way, not to obstruct

  through mediation. How much more would we value old sources

  if instead of writers paraphrasing one another they had actually

  used quotations? How much that is ambiguous would instead be

  clear? In studying Bruno, for instance, I used secondary sources at

  first. I was surprised by how much they disagree with one another.

  Whenever a writer mentioned four or five Catholic accusations

  against Bruno, I wondered how many others were there? How do

  those few fit into the larger set? Only when I checked the primary

  sources themselves did I realize that there were dozens of accusations. Yet to convey them all is very unusual. When one finds a secondary source that does so, then finally both the trees and the

  forest become simultan eously visible. 2 Accordingly, I have worked to synthesize certain claims not just into paragraphs but to dissect

  them as informative lists in which I have tried to be faithful to the

  originals and to organize the evidence more clearly than in a paragraph format. Such lists convey how the most relevant particulars fit into the broad collection.

  For centuries, people have interpreted the ideas of Pythagoras

  and his followers in many different ways. In a previous book, The

  Cult of Pythagoras, I showed how scholars have radically disagreed

  in their interpretations. Some said that Pythagoras was a polytheist,

  others that he believed in one God, or that he was an atheist. Others

  said that he was a pantheist, or that he imitated Jewish doctrines, or

  that he was a Buddhist, or that he believed in the Holy Trinity, and

  so forth. Some writers say that Pythagoras was an aristocrat. For

  others he was a poor, revolutionary exile. Others say that he was a

  socialist, others that he was a communist, while others have argued

  that he was an early pioneer of democratic thought. Owing to such