The Sleepwalkers
Since that experiment is also legendary, Prof. Singer's comparison contains an ironic truth; but this triple misstatement is characteristic of the power of the Galileo myth over some eminent historians of science. Prof. Singer also seems to believe that Galileo invented the telescope (op. cit., 217), that in Tycho's system "the sun revolves round the earth in twenty-four hours carrying all the planets with it" ( ibid., p. 183 ), that Kepler's Third Law was "enunciated in the Epitome Astronomiae ( ibid., p. 205 ), etc.
13
Cf. Zinner, op. cit., p. 514.
14
Le Operazioni delle Compasso Geometrico e Militare, Padova. 1606; Opere II, pp. 362-405.
15
Usus et Fabrica Circiui Cuiusdam Proporziones, Padova, 1607; Opere II, pp. 425-511.
16
Capra's teacher was the distinguished astronomer Simon Marius ( 1573-1624), discoverer of the Andromeda Nebula, with whom Galileo later became involved in another priority quarrel. See below, p. 468.
17
"Letter to B. Landucci", quoted by Gebler, Galileo Galilei and the Roman Curia, London, 1879, p. 19.
18
George Fugger (a member of the famous bankers family) in a letter to Kepler. 16.4. 1610, G. W., Vol. XVI, p. 302.
18a
Cf. Zinner, op. cit., p. 345 f.
19
This refers to the first, Latin edition.
20
Paradise Lost, book ii, J. 890.
20a
Peregrinatio contra Nuncium Sydereum, Mantua, 1610.
21
Ignatius his Conclave.
22
Opere, ed. F. Milano-Napoli Flora, 1953, P. 887seq.
23
Ibid., p. 894seq.
24
28.5.1610, G. W., Vol. XVI, p. 314.
25
Quoted by E. Rosen, The Naming of the Telescope, New York, 1947.
26
"Letter to Horky, 9.8.1610", G. W., Vol. XVI, p. 323.
26a
"Poor Kepler is unable to stem the feeling against Your Excellency, for Magini has written three letters, which were confirmed by 24 learned men from Bologna, to give effect that they had been present when you tried to demonstrate your discoveries ... but failed to see what you pretended to show them." M. Hasdale to Galileo, 15.4 and 28.4. 1610, G. W. Vol, XVI, pp 300f, 308.
27
G. W., Vol. XVI, p. 319seq.
27a
It was probably this letter which lead Prof. de Santillana to the erroneous statement: "It took even Kepler, always generous and open-minded, a whole five months before rallying to the cause of the telescope... His first Dissertaro cure Nuncio sidereo, of April, 1610, is full of reservations.'' ( Dialogue on the Great World Systems, Chicago, I9 37), p. 98 n.) Kepler's reservations referred, as we saw, to the priority of the invention of the telescope, not to Galileo's discoveries with it.
28
G. W., Vol. XVI, p. 327seq.
29
Except for a short note of introduction to Kepler, which Galileo gave a traveller seventeen years later, in 1627. Opere XIII, p. 374 f.
30
Gebler, op. cit., p. 24.
31
At least, that seems to be the meaning. The word "umbistineum" does not exist and may either be derived from "ambustus", burnt up, or "umbo"=boss, projection.
32
9.1.1611, G. W., Vol. XVI, p. 356seq.
33
Narratio de Observatis a se quatuor Iovis sattelitibus erronibus.
34
25.10.1610, G. W., Vol. XVI, p. 341.
Part IV Chapter IX. CHAOS AND HARMONY
1
The book should really be called "Dioptrics and Catoptrics", for it deals with both refraction and reflection.
2
Except for the Preface.
3
Ad Vitellionem Paralipomena, quibus Astronomiae Pars Optica.
4
3.4.1611, G. W., Vol. XVI, p. 373seq.
5
Dedication of the Eclogae Chronicae, 13.4.1612, quoted in Johannes Kepler in seinen Briefen, Vol. I, p. 391seq.
6
Ca., p. 243.
7
Ca., p. 252 f.
8
Ca., p. 300.
9
Galileo, as we shall see, was submitted to the much milder form of territio verbalis, without actually being led into the torture chamber.
10
Quoted in Johannes Kepler in seinen Briefen, Vol. II, p. 183 f.
11
Harmonices Mundi Libri V, Linz, 1619. The work is sometimes erroneously referred to as "Harmonices", as if the "s" stood for the plural, whereas it stands, of course, for the genitive.
12
Kepler's translation of the word is unwissbar.
13
Harmonice Mundi, Bk. V, Cap. 4.
14
Loc. cit.
15
Ibid., Cap. 7.
16
Dedication of the Ephemerides for 1620 to Lord Napier.
17
Ibid.
18
Harmonice Mundi, Introduction to Book V.
19
"Sed res est certissima exactissimaque, quod proportio, quae est inter binorum quorumconque planetarum tempora periodica, sit praecise sesquialtera proportionis mediarum distantiarum, id est orbium ipsorum." ( Ibid, V, Cap. 3, Proposition No. 8. )
20
Loc. cit.
21
Loc. cit.
22
Ibid., appendix to Book V.
Part IV Chapter X. COMPUTING A BRIDE
1
G.W., Vol. XVII, p. 79 seq. The following is a compressed version.
Part IV Chapter XI. THE LAST YEARS
1
"To Bianchi, 17.2.1619", G.W., Vol. XVII p. 321 seq.
2
"To Bernegger, 20.5.1624", Johannes Kepler in seinen Briefen, II, p. 205 f.
3
1.10.1626. Ibid., II, p. 222. ff.
4
Loc. cit.
5
Kepler became acquainted with Napier's logarithms in 1617: "A Scottish baron has appeared on the scene (his name I have forgotten) who has done an excellent thing by transforming all multiplication and division into addition and subtraction..." ( Ibid., II, p. 101.) Since Napier did not at first explain the principle behind it, the thing looked like black magic and was received with scepticism. Old Maestlin remarked: "It is not fitting for a professor of mathematics to manifest childish joy just because reckoning is made easier." (Ca., p. 368.)
6
To Bernegger, 20.5.1624, see note 2.
7
Ca., p. 302.
8
"To Bernegger, 6.4.1627", Johannes Kepler in seinen Briefen, 11, p. 236 seq.
9
"To Bernegger, 22.7.1629", ibid., p. 292.
10
"To Bernegger, 2.3.1629", ibid., p. 284 f.
11
"To Bernegger, 29.4.1629", ibid., p. 286 f.
12
"To Ph. Mueller, 27.10.1629", ibid., p. 297.
13
Cf. Marjorie Nicolson essay, Kepler, the Somnium, and John Donne, in her Science and Imagination, Oxford, 1956.
14
Kepler added the following note to this passage:
"We can feel the warmth of the moonlight with the help of an apparatus. For if one gathers the rays of the full moon in a concave parabolical or spherical mirror, then one feels in its focus, where the rays meet, a warm breath, as it were. I noticed that in Linz when I was engaged in other experiments with mirrors, without thinking of the warmth; I involuntarily turned around to see whether somebody was breathing on my hand."
As Ludwig Gunther, who edited and translated the Somnium ( Kepler Traum vom Mond, Leipzig, 1898), pointed out, this passage establishes Kepler's priority in discovering that the moon reflects not only the light, but also some of the heat of the sun – a fact which was by no means obvious and which (according t
o Gunther, p. 131) was only established by C. V. Boyse in the 1890s. The ancients believed that the sunlight lost all its warmth when reflected by the moon (cf. Plutarch On the Face in the Moon Disc).
15
Letter to Bartsch, 6.11.1629, Johannes Kepler in seinen Briefen, II, p. 303.
16
"To Ph. Mueller, 22.4.1630", ibid, p. 316.
17
"Bartsch to Ph. Mueller, 3.1.1631", ibid. II, p. 329.
18
Ibid. II, p. 325.
19
Ca., p. 431.
20
Quoted by "S. Lansius to anon., 24.1.1631", Johannes Kepler in seinen Briefen, II, p. 333.
21
From which expression one might infer that they refused him the last sacraments.
22
To Bartsch, Johannes Kepler in seinen Briefen, II, p. 308.
PART FIVE THE PARTING OF THE WAYS
Part V Chapter I. THE BURDEN OF PROOF
1
"To Cosmo II, 31.5.1611", quoted by Gebler, op. cit., p. 36.
2
The term was devised by a member of the Lynxes, Demisiani, and announced at the banquet on 14 April, 1611. See E. Rosen, The Naming of the Telescope, New York, 1947.
3
Letters on Sunspots, Third Letter, 1612, transl. Stillman Drake , op. cit., p. 126 f.
4
About this hilarious chapter of science-mythology, see Lane Cooper, Aristotle, Galileo and the Tower of Pisa, Ithaca, 1935.
5
Zinner, op. cit., p. 346.
6
This episode was a typically Keplerian comedy of errors. On 28 May, 1607, Kepler had observed the sun through a kind of improvised camera obscura. It consisted in narrow gaps between the shingles on the roof of his house in Prague. The gaps let the rain into the attic, but each gap deputised for the aperture of a (lenseless) camera; by holding a sheet of paper under the slit, Kepler obtained a projected image of the sun. On that particular day he observed on the projected disc of the sun "a small, almost black dot, approximately like a meagre flea". When he brought the paper closer to the gap, thus enlarging the disc to the size of his palm, the spot grew to the size of "a small mouse". Kepler was convinced that the spot was the shadow of Mercury, and that he was observing a transit of that planet across the disc of the sun. He raced up the Hradshin to the Emperor's palace, and conveyed the news by way of a flunkey to Rudolph; raced down again, induced several people to convince themselves of the existence of the black dot and to sign documents testifying to it, and in 1609 published a treatise on the event: Mercurius in Sole.
7
Il Saggiatore, quoted by Zinner, p. 362.
8
Letters on Sunspots, transl. Stillman Drake, op. cit., p. 100.
8
Ibid., p. 113 f.
9
Ibid., p. 144.
10
"Conti to Galileo, 7.7.1612". Quoted by G. de Santillana, The Crime of Galileo, Chicago, 1955, p. 27 f.
11
Opere, XI, 427, quoted by Stillman Drake, p. 146 f. A number of historians (including, recently, Professor de Santillana) have tried to lend this incident more weight by stating that Lorini had preached a public sermon against Galileo. But had he done so ("on All Souls' Day", as Santillana says), it would be fantastic to assume that he could have denied the fact in writing; besides, Galileo himself says that the incident occurred "in private discussion". (Opere V, 291, quoted by Drake, p. 147 n.)
12
Opere, XI, p. 605 f.; quoted by Drake, p. 151 f.
13
Transl. Drake, op. cit., p. 175.
14
Ibid., pp. 181-3.
15
Ibid., p. 192 f.
16
Ibid., p. 194.
17
Ibid., p. 194 f.
18
Ibid., p. 213.
19
10.1.1615. Quoted by Gebler, op. cit., p. 52.
20
Opere, XII, p. 123. Quoted by Drake, p. 155.
21
Transl. Santillana, op. cit., p. 45 f.
21a
Gebler, op. cit., p. 53.
22
He maintained, i.a., "that Christ was not God, merely an unusually skilled magician ... and that the Devil will be saved." (Catholic Encyclopaedia on Bruno.)
22a
It is surprising to note how indifferently scholars reacted to Bruno's martyrdom, at any rate in Germany. This is illustrated by Kepler's voluminous correspondence, in which every subject under the sky is discussed, but Bruno is hardly mentioned. One of Kepler's favourite pen-friends during his Prague period was the physician Brengger in Kaltbeuren, a man of great erudition and a wide range of interests. In a letter dated 1 September, 1607, Brengger mentioned in passing the theory of "Jordano Bruno of Nola" about the plurality of worlds. This was nearly eight years after Bruno had been executed, but Brengger was evidently unaware of the fact. Kepler answered (on 30 November, 1607) that "not only the unfortunate Bruno, who was roasted on coals in Rome, but my venerated Tycho too believed that the stars are inhabited." (He actually committed one of his dreadful puns: "... infelix ille Prunus prunis tostus Romae.") In his next letter ( 7 March, 1608) Brengger wrote: "You say that Jordano Bruno was roasted on coals, from which I gather that he was burnt", and inquired why this had been done: "I pity the man." Kepler answered (on 5 April): "That Bruno was burnt in Rome I learnt from Master Wackher; he suffered his fate steadfastly. He had asserted the vanity of all religions and had substituted circles and points for God." Brengger concluded that Bruno must have been insane and wondered where his fortitude had come from if he denied God ( 25 May, 1608). This, then, was the comment of two contemporary scholars on the burning alive of Giordano Bruno. (G. W., Vol. XVI, pp. 39, 116, 142, 166.)
23
Opere, XII, pp. 145-7, quoted by Drake, p. 158.
24
Opere, XII, p. 151, quoted by Drake, p. 159.
25
Lettera del R.P. Maestro Paolo Antonio Foscarini, Carmelitano, sopra l'opinione de i Pittagorici e del Copernico della mobilita della Terra e stabilita del Sole, e il nuove Sisteme del Mondo, Napoli, 1615.
26
Gebler, op. cit., p. 61.
27
Santillana, op. cit., p. 91.
28
Sherwood Taylor, op. cit., p. 85.
29
Opere (ed. F. Flora), pp. 999-1007.
30
Opere, XII, p. 171 f. Transl. Drake, pp. 162-4, and Santillana , pp. 98-100.
31
Opere, XII, pp. 183-5. Transl. Drake, pp. 165-7.
32
Santillana, op. cit., p. 118.
33
Drake, p. 170.
34
Santillana, op. cit., p. 110.
35
"Letter to Cardinal Allessandro d'Este, 20.1.1616", transl. Santillana, p. 112 f.
36
Ibid., p. 117.
37
Ibid., p. 116.
38
Dialogue on the Great World Systems, Salusbury transl., ed. Santillana, Chicago, 1953, p. 469; henceforth referred to as Dialogue. The Italian title Dialogo ... sopra i due Massime Sistemi del Mondo expressly mentions two great world systems, the Ptolemaic and the Copernican; but since I have followed Santillana's edition of the Salusbury translation I must refer to it by the title which the editor has given it.
38a
He explained this as due to secondary causes operating in inland seas such as the Mediterranean and the Adriatic. See below, pp. 465, 479.
39
H. Butterfield, op. cit., p. 63.
40
Transl. Santillana, op. cit., p. 119.
41
Some of Galileo's biographers are anxious to give the impression that the decree of 5 March was not caused by Galileo's persistent provocations, but the result of a coldly planned inquisitorial campaign to stifle the voice of science. To prove this, they maintain that the convocation
of the Qualifiers was not an ad hoc decision, provoked either by Orsini's démarche with the Pope or by Galileo's general behaviour in Rome, but that it was the conclusion of continued inquisitorial proceedings, starting with the denunciation by Lorini and Caccini, or even earlier. The "even earlier" refers to a meeting of the Congregation of the Holy Office back in 1611 at which Bellarmine introduced "a small item on the agenda": "Find out whether, in the proceedings against Dr. Cesare Cremonini, there is a mention of Galileo, Professor of Philosophy and Mathematics." Cremonini was an Aristotelian enemy of Galileo's at the University of Padua; he was never brought to trial. The entry dates from the days of Galileo's triumphant visit in Rome, and the matter is never again mentioned in the file. Then there is nothing in the file for five years, until Lorini's charges against the "Letter to Castelli", which are dismissed, Caccini's testimony in February, and the testimonies of Ximenes and Atavante in November, which brought the proceedings to a close.
But Caccini had mentioned the "Letters on Sunspots", and on 25 November there is a note in the file referring to an Instruction by the Congregation: "See the 'Letters on Sunspots' by the said Galile". Then nothing until 23 February next year, when the Qualifiers are convoked to pronounce on the two propositions submitted to them, but without mention of either the "Sunspots" or Galileo's name. Nevertheless, the abovementioned entry of 25 November is construed as indicating that the proceedings had never been dropped, merely delayed, and that the calling in of the Qualifiers was the final and inevitable result of "historic fatality".
The fact is that the Qualifiers were not asked to see or censure the "Letters on Sunspots"; that whoever looked at the book must have seen at once that it contained a single and unobjectionable reference to the Copernican system as a hypothesis; and that the matter was dismissed as the Cremonini and Caccini and Lorini denunciations had been dismissed before.
The absence of any preconceived plan is also illustrated by Bellarmine's letter to Foscarini, and by the clumsy wording of the second question to the Qualifiers, that the earth moves "according to the whole of itself, also with a diurnal motion" (ma si move secondo sè tutta, etiam di moto diurno). Santillana has shown (op. cit., p. 139) that the words, which really make no sense, were picked out of Caccini's garbled version of Copernicanism. If the convocation of the Qualifiers had been planned beforehand, and not an ad hoc measure ordered by an irate Pope, the Inquisitor in charge of formulating the questions could surely have prepared something more precise than the phrase he picked from a hurried perusal of the file.