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ASTRONOMERS AND EXTRATERRESTRIALS
59
sought to determine God's design for their domiciles. Ironically, these
thl'eepioneers of stellar astronomy may have had no more concern aboqt
stars than their contemporaries; rather, it was inhabited planetary sys~
temsthat interested them and that they sought to arrange .into systems.
The Milky Way for them was not primarily a giant array of glowing
globes, ,but rather a visible coHection of sources of heat and light serving
the myriads of beings living on the admittedly unobservable planets of
the stellar systems. If it is correct that to some extent their pluralism
mbtivated and aided them in their search for those ideas that have made
their books famous, this would illustrate Lambert's statement in his Cosmtbiogicai Letters (p. 46) that a teleological approach frequently has
heuristic benefits .
... ,Wright, Kant, and Lambert wrote their books in the middle years of
the Enlightenment, which R. G. Collingwood characterized as the age of
the" endeavor to "secularize every department of human life and
thought."46 Their books, which can be seen. as extended endorsements of
Young's "An undevout astronomer is mad," at first glance fit Collingwood's characterization no better than they harmonize with the Enlightenment as an age of empiricism, Newtonianism, and this-worldliness., Wright, Kant, and Lambert were interested in, and to differing
degrees informed about, the telescopic observatibns of their contemporaries, but analogical argumentation and the principle of plenitude were
more influential factors in their thought. Newton was known to them to
various .degrees, but they went far beyond and in some cases contrary to
hiucientil1c and methodological principles. Wright's spherical shell univ.erses, Kant's dull Mercurians and super Saturnians, and Lambert's cometary astronomers are now seen as bizarre companions to the more durable doctrines developed in their books. In a deeper sense, however, .
support for Collingwood's characterization can be found in Kant's and
Lambert's angelic superbeings and in Wright's God-centered shells when
it, is .suggested that these three- authors were in fact attempting to transform. traditional religious notions by interpreting them in physical terms.
Thi$ blending of the' spiritual and the celestial was, of course, not confined to these three.authors and will be encountered again and again in
this book, not'least in the writings of th~ greatest of sidereal astronomers,
William Herschel, who without knowing of their books embarked in the
If77()S and I780s on much the same quest and carried it farther.
' . .1.
Sir William Herschel: "promise not to call me a Lunatic"
Before discussing Herschel, it will be convenient to consider James Ferguson (I7IO.... 76), who, it will be suggested, importantly influenced Her-
.,(.,.'-
60
FROM 1750 TO 1800
schel. Although Ferguson's formal education consisted of only three
months in a Scottish grammar school, this shepherd turned instrument
maker and astronomical author published a number of popular scientific
treatises, most notably his Astronomy Explained upon Sir Isaac Newton's Principles (1756), which attained seventeen editions. Its appeal was
due not only to its clear if elementary explanations but also to its pious
pluralism. Describing astronomy as "the most sublime, the, most interesting, and the most useful" of the sciences, Ferguson urges thatthrough it,
our understanding becomes "clearly convinced, and affected with the
conviction, of the existence, wisdom, power, goodness, and superintendency of the SUPREME BEING!"47 These characteristics of the Creator
assure Ferguson that God made the stars not primarily to illuminate our
earth, which our moon does far better, but to serve their own systems of
planets. As he states, astronomy ','discovers to us . . . an inconceivable
number of suns, systems, and Worlds, dispersed through boundless
space. • . .n And he adds: "From what we know of our own System, it
may be reasonably concluded that all the' rest are with equal wisdom
contrived, situated, and provided with accommodations for rational inhabitants." In short, Ferguson's universe contains: "Thousands of thou~
sands of Suns . . . attended by ten thousand times ten thousand Worlds
. . . peopled with myriads of intelligent beings, formed for endlessprd-,
gression in perfection and felicity." (pp. 3-5) .
Ferguson focuses chiefly on the solar system, concerning which he
notes that the outer planets are provided with extra moons, and in the
case of Saturn with a ring, to illuminate the nights of their inhabitants~ ,
He states that "by the assistance of telescopes we observe the Moon to be'
full of high mountains, large valleys, and deep cavities. These similaritiel(:
leave us no room to doubt but that all the Planets and Moons in
System are designed as commodious habitations for creatures endowedt
with capacities of knowing and adoring their beneficent Creator." (p. ~
So confident was he of lunar life that he remarks that the earth not only
"a moon to the moon" but also, by having a more or less fixed position
the moon's sky, allows lunarians to determine lunar longitude (pp;
18). Concernihg comets, he admits: "The extreme heat, the dense
phere, the chaotic state of the comets, seem at first sight to indicate
altogether unfit. . . for rational beings. . . ." Nonetheless he populate'!
them, urging that God's "infinite power and goodness" enable him
"make creatures suited to all states and circumstances." That God
acts, Ferguson asserts, is shown by the fact that "matter exists only
the sake of intelligence [and is] always . . . pregnant with life, or
sarily subservient thereto. . . . " (pp. 2.7-8)
,
That teleology more than the telescope, that religious conviction
than rigorous calculation inspired Ferguson to such fancies goes withntifl,l!
ASTRONOMERS AND EXTRATERRESTRIALS
61
~aying.Nonetheless, his book was sufficiently rich in astronomical infori,rtation that when the EncyClopaedia Britannica was launched in 177I,
:jhe editors presented as the long, unsigned article "Astronomy" an ab'.reviated version of Ferguson's Astonomy Explained. This energetic au~or carried his enthusiasm for pluralist astronomy to the English public
itt other ways as well, for example, by popular lectures on astronomy in
such cities as Bath, Bristol, and London. Although he was not the first to
present pluralism to British children, this having been done in 1758 in a
book that has been attributed by some to John Newbery and by others to
Oliver Goldsmith,48 Ferguson's Easy Introduction to Astronomy for
Young Gentlemen and Ladies (I768) was one of the most successful
works of its kind, attaining a dozen editions. Using a dialogue form in
this book, he has his Eudosia exclaim: "I cannot imagine the inhabitants
of our earth to be better than those of other planets. On the contrary, I
'Would fain hope that they have not acted so absurdly with respect to
[God], as we have done."49 Ferguson's talents were recognized by the
'Royal Society, which elected him to membership, and by King George III,
who bestowed fifty pounds per year on him. Of more immediate rele•\tince are the indications that his pluralist claims influenced three authors
who became central figures in the pluralist debate: Tom Paine, David
,;Brewster; and William Herschel.
:\;~·r:
.
,1!':'The'eminence of Sir William Herschel (1738-182.2.) among astrono'fIi~rs:iS'indisputable, but recent researches may require a revision in the
of the career of this Bath musician who became a full-time
:ronomer only after his I78I discovery of Uranus when King George
'¥c:sclted him from "crochets and quavers" by funding his investigaTraditionally Herschel has been presented as a tireless telescopic
as a model empiricist who, as Edwin Hubble pUt it, did not,
speculate about the nebulae but observed them by the thou~u'Herschel has also been seen as eschewing the philosophical conof the Enlightenment to concentrate on what his telescopes
reveal about the timeless night sky, which he studied with a de>less easily detected in the physicotheological excursions of
Lambert, and Ferguson. Sl Attractive as this image of him may
Ul'accords with some of the recent researches on Herschel published
11 Cambridge University by Michael Hoskin and some of his former
or with materials I have uncovered in Herschel's unpublished
Illllll'ripts.S2 Considered conjointly, these studies suggest (I) thilt Hersless an isolated empiricist than a speculatively inclined celestial
quixotically caught up in a quest for evidence of extraterrestrithat many of his efforts make most sense when seen as attempts to
IlHsrorm pluralism from being a delight of poets, a doctrine of metaphy-
62.
FROM 1750 TO 1800
sicians, and a dogma of physicotheologians into a demonstration of astronomers, and (3) that pluralism was a core component in Herschel's
research program and as such influenced many of his astronomical endeavors, especially (if far from exclusively) in his fonnative years.
About Herschel's development from 1753, when he joined his father's
Hanov~rian regimental band as an oboist, to the mid-I77oS, when astronomy became the consuming avocation of the by then Bath organist,
less is known than one might hope. That his father had instilled in him a
love of learning is indicated by his determination in I756, while stationed
with the band in England, to read Locke's Essary Concerning Human
Understanding. That this -zeal did not diminish after I757, when he
forsook the band to work as a musician in England, is sho~n by the fact
that by I76I he had read Leibniz's Theodicie. His growing attachment
to astronomy is reflected in his I773 purchase of Ferguson's Astronomy.
Herschel's interest in these three books has been documented by his
biographers;s3 what has not been i10ted is that all three contain endorsements of pluralism. 54 That Herschel's involvement with Ferguson may
have gone beyond the Astronomy, which he took "to bed with a bason
[sic] of milk or a glass of water" for a number of months,5s is suggested
by the fact that Ferguson lectured in Bath in I767 and again in I774.
Given that by I773 Herschel was sufficiently committed to astronomy
that he was constructing his own telescopes, it seems probable that he
attended one or both of Fergusoi1'S lecture series. 56 Moreover, internal
evidences from Herschel's writings point to the conclusion that Herschel
was powerfully influenced by Ferguson's conception of astronomy, including its pluralist component.
Herschel's scientific debut should be dated not from his I78I discovery
of Uranus butfrom May I780, when two of his papers were read to the
Royal Society, the longer of these being his "Astronomical Observations
Relating to the Mountains of the Moon." Behind this paper lies a fascinating story, recoverable from Herschel's unpublished manuscripts,
which provide evidence that at that time he believed that he was already
on the verge of a discovery more revolutionary than his detection of
Uranus. Herschel's lunar mountain paper led Nevil Maskelyne, the
Astronomer Royal, to request details from Herschel on his methods of
measurement and to ask about his statement in that paper that "the
knowledge of the construction of the Moon leads us insensibly to several
consequences. • • such as the great probability, not to say almost abso-lute certainty, _of her being inhabited."s7 No 'doubt Maskelyne's query
about Herschel's lunar life claim was intended to suggest the impropriety
of its inclusion in a formal scientific paper. The hint was hardly taken;
instead, Herschel responded with a disquisition that Maskelyne chose
not to expose to the public when he appended the measurement section
of Herschel's letter to the eventually published paper. Only with the I9 I 2.
ASTRONOMERS AND EXTRATERRESTRIALS
63
Rublication of Herschel's collected papers did his full letter become
known. Although Herschel was aware in 1780 oithe e~idence against a
!hnar atmosphere, based on the sharpness with which the moon occults
jars, and had himself made observations supportive of this conclusion (I,
tP. xci-xcii), he nonetheless argues for lunar life in this letter,suggesting
that his belief in it "may perhaps be ascribed to a certain Enthusiasm
which an observer, but young in the Science of Astronomy can hardly
divest himself of when- he sees such wonders.•.." After requesting
Maskelyne to "promise not to call me a Lunatic," he quotes extensively
from a document drafted eighteen months earlier in which heluses arguments from analogy as applied to the similarities between the earth and
the moon as a basis for asking:
. . . who can say that it is not extremely probable, nay beyond doubt, that there
must be inhabitants on the Moon of some kind or other? Moreover it is perhaps
not altogether so certain that the moon is out of the reach of observation in this
respect. I hope, and am convinced, that some time or other very evident signs of
life will be discovered on the moon. (I, p. xc)
Maskelyne's dismay cannot have diminished when later in the letter
Herschel explains: "The earth acts the part of a Carriage, a heavenly
waggon to carry about the more delicate moon, to whom it is destined to
give a glorious light. • . • For my part, were 1to chuse betwe~n the Earth
and Moon I should not hesitate to fix upon the moon for my habitation."
, (I, p. xc)
As unrestrained as Herschel's letter to Maskelyne appears, it may have
taken some reserve on Herschel's part to resist making even stronger
statements. This is evident from Herschel's unpublished compilation of
his lunar observations, which reveals that in 1780 Herschel believed he
already possessed substantial observational evidences of life on the
moon. Jlor example, among the earliest of his lunar observations is that
dated May 2.8, 1776, when with a newly acquired telescope, he saw
. . . sOmething I had never observed before, which I ascribed to the power and
distinctness of my Instrument, but which may perhaps be an optical fallacy....
I believed to perceive something which I immediately took to be growing substances. I will not call them Trees as from their size they can hardly come under
tJtat qenominlJtion, or if I do, it must be understood in that extended signification
So as to take in any size how great soever.... My attention was chiefly directed
to'Mate humorum, and this I now believe to be a forest, this word being also
- taken in its proper extended signification as consisting of such large growing
substances.58
~erschel proceeds to sketch the forest (Figure 2..2.) and to analyze
whether or not a lunar forest would be visibl~ from the earth:
, Ql,lr tallest trees would vanish at that distance; It is not impossible but that the
vegetable Creation (and indeed the animal too) may be of a much larger size on
the Moon than it is here; tho' perhaps not very likely. And I suppose that the
64
FROM 17:50 TO 1800
ASTRONOMERS AND EXTRATERRESTRIALS
6S
ttuch rarer than ours and of consequence not so capable of refracting and (by
,,,eans of clouds shining therein) reflecting the light of the Sun, it is natural
enough to suppose that a Circus will remedy this deficiency. For in that shape of
Building one half will have the direct and the other half the reflected light of the
·Sun. Perhaps, then on the Moon every town is one very large Circus? .. Should
:~his be true ought we not to watch the erection of any new small Circus as the
.~unarians may the Building of a new Town on the Earth. Our telescopes will do
Jhis. . . . By reflecting a little on this subject I am almost convinced that those
.jnumberless small Circuses we see on the Moon are the works of the Lunarians
and may be called their Towns. . . . Now if we could discover any new erection
it is evident an exact list of those Towns that are already built will be necessary.
,But ,this is no easy undertaking to make out, and will require the observation of
:many a careful Astronomer and the most capital Instruments that can be had.
~However this is what I will begin.60
!
~'
,.:
r
Figure 2..2.. A portion of Herschel's unpublished notes on his lunar
observations, including his drawing of the lunar forest he believed he
had observed. (Courtesy of the Royal Astronomical Society.)
borders of forests, to be visible, would require Trees at least 4, S or 6 times the
height of ours.
But the thought of Forests or Lawns and Pastures stilI remains exceedingly
probable 'with me, as that will much better account for the different Colour, than
different coloured soils can do. 59
Herschel's ambivalence about these observations led him in late 177 8
to compose a new analysis, portions of which he quoted in his Maskelyne
letter, but the following passages, which show that Herschel believed he
had evidence not only of forests but also of lunar towns, were not ineluded:
As upon the Earth several Alterations have been, and are daily, made of a size
sufficient to be seen by the Inhabitants. of the Moon, stich as building Towns,
cutting.canals f~r ~avigation, making turnpike roads. &:c: may we not ~pect
something of a slmdar Nature on the Moon? - There IS a reason to be assigned
for circular-Buildings on the Moon, which is that, as the Atmosphere there is
Having adopted this remarkable research program, which probably was
no sma.ll factor in his efforts to build better telescopes, Herschel set about
:making numerous lunar observations. His lunar observation book shows
fthat to classify the lunar "circuses" he chose at first the labels "Metropolis, Cities; Villages" but finally satisfied himself with the more prosaic
terms "Large places, Middling places, Small places."61 His June 17,
'1779, entry records his observation of "a Cut or Canal that seems evidently to be the effect of Art rather than of Nature," and a month later,
',seeing a new spot in the Mare Crisium region, he writes: ". . . I find it is
'a 'city."62 Extensive lunar observations from 1780 and 1781 are re'cor:ded, many from the earlier year being height determinations of lunar
'mOUntains. The latter year produced richer results, his observations' of
late June yielding numerous patches of "vegetation," "turnpike roads,"
arid "circuses. "63 On another evening he reports regions "tinged with
green."64 In 1783 he records that a star passing behind the moon disappeiued slowly, indicating a lunar atmosphere, and also in 1783 he espies
'''t\\rosmall pyramids."65 Herschel's lunar observations seem to be far less
fteq;uent after 1183, even though in that year he confided to Alexander
Wilson, a Scottish astronomer, what he had done and hoped to do toward establishing the existence of life on our moon:
!;
.' . The attempt of finding traces of animation in the Moon has now been 5 or 6
years one of those I have endeavoured to render practicable, and tho' I have met
with rio self evident or occular demonstration of the moons being inhabited, yet
do i still hope that a good many of my observations will at least render the
'!'easons we may alledge from analogy more forcible. The highest power I have
'hitherto been able conveniently to use in viewing the Moon is 932.. Hence it is
~asy to calculate what so~t of Objects we may expect to see. However the many
interruptions [e.g., his discovery of Uranus!] I have within these last two years
'met with, have prevented my Observations on this subject to be so frequent as I
now, with improved instruments, hope to make th~m. Very happily our gracious
sOvereign has enabled me to follow a study, which from ml excessive attachment
to it I formerly followed in spite of other employments. 6
FROM 1750 TO 1800
ASTRONOMERS AND EXTRATERRESTRIALS
It is unknown how many other astronomers were aware of Herschel's
hopes for detecting lunar life; one suspects that part of the process of his
professionalization was to learn that discoursing on such matters gave
support to those who thought him "fit for bedlam."67 Whatever th~ case
may be, it is a mark of his professionalism that never in his published
writings did he claim observational evidence of lunar life. Probably he
dismissed his observations of "forests," "cities," "turnpike roads," and
such as among those tricks of the telescope that he lainented in a 1782.
letter, to Alexander Aubert:
These instruments have played me so many tricks that I have at last found them
out in many of their humors. . . . I have tortured them with powers, flattered
them with attendance to find out the critical moments when they would act, tried
them with specula of a short and of a long focus, a large aperture and a narrow
one; it would be hard if they had not been kind to me atJast. 68
should view the exclamation of the poetess Fanny Burney, who in 1786
'visited Herschel: "he has discovered fifteen hundred universes! How
" many more he may find who can conjecture?"69
The continuing intensity of Herschel's pluralist convictions is clearly
, revealed in a 1795 paper, especially when this paper is seen in relation to
an event reported in the Gentleman's Magazitte"for 1787. A certain Dr.
Elliot was brought to trial in London for having set fire to a lady's cloak
by firing a pair of pistols near it. Insanity was the plea made for Elliot, in
support of which a Dr. Simmons recounted examples of Elliot's bizarre
behavior, especially his having prepared 'a paper for submission to the'
Royal Society in which he maintained the sun to be inhabited. 70 This
incident leads one to wonder what may have been the .reaction among
readers of the Royal Society's Philosophical Transactions when in I795
they encountered a paper in which Herschel theorized that the sun consists of a cool, solid, spherical interior above which floats an opaque layer
of clouds that simultaneously reflects the rays of the glowing exterior
region and shields the interior region from excessive heat and light. As he
states: "The sun . . • appears to be nothing else than a very eminent,
large, and lucid planet, evidently the first, or in strictness of speaking, the
only primary one of our system. . . . Its similarity to the other globes of
the solar system . . . leads us to suppose that it is most probably . . .
inhabited. . . by beings whose organs are adapted to the peculiar circumstances of that vast globe."71 Herschel contrasts his theory with that
of "fanciful poets" who portray the sun "as a fit place for the punishment
of the wicked," urging that his claim rests "upon astronomical principles." (I, p. 479) He argues his case by means of analogy, claiming that
telescopes reveal that the moon has numerous similarities to the earth.
The obvious differences he dismisses by noting that terrestrial beings
flourish in a variety of circumstances:
While man walks upon the ground, the birds fly in the air, and fishes swim in
water; we can certainly not object to the conveniences afforded by the moon, if
those that are to inhabit its regions are fitted to their conditions as well as we on
this globe are to ours. An absolute, or total sameness, seems rather to denote
imperfections, such as nature never exposes to our view . . . . (I, p. 48r)
66
Herschel was convinced that life exists not only on the moon but al,so
on the planets and their satellites. The similal,'ities between the earth and
Mars are stressed in his 1784 paper on that planet to support his repeated
references to the inhabitants of Mars (I, pp. 138, I48, I56). In fact, his
concluding comment is that Mars "has a considerable but moderate
atmosphere, so that its inhabitants probably enjoy a situation in many
respects similar to ours." (I, p. r 56) In other papers he casually refers to
"the inhabitants of Saturn or the-Georgian planet [Uranus]" (I, p. 42.2.)
and to "the inhabitants of the satellites of Jupiter, Saturn, and the Georgian planet." (I, p. 481) Shortly after the discoveries of Ceres and Pallas,
Herschel reported his observation that they "have an atmosphere of
considerable extent." (II, p. I94) This spurious observation, one suspects, may have had its origin in his pluralist proclivities.
Herschel's writings show that he also believed that inhabited planets
orbit other stars. In a 1783 paper, he justifies observations of the variable
star Algol by claiming that such observations could verify the existence of
"a plurality of solar and planetary systems." (I, p. cvii) Although admitting such extra-solar-system planets "can never be perceived by us" (I,
pp. 416-17), he states (1789) that every star "is probably of as much
consequence to a system of planets, satellites, and comets,' as our own
sun . . . . " (I, p. 330) The point is most explicit in his 1795 statement
that analogy supports the conclusion that "since stars appear to be suns,
and suns, according to the common opinion, are bodies that serve to
enlighten, warm, and sustain a system of planets, we may have an idea of
numberless globes that serve for the habitation of living creatures." (I, p.
482.) The far-reaching significance of this claim is seen when itis recalled
that during the 1780s Herschel had come to believe that most of the
hundreds of nebulae he had detected with his telescopes were entire
universes comparable to the Milky Way. It is within this context that one
67
Finally, he urges that terrestrials who deny life to the sun have no more
logic on their side than inhabitants of a planetary satellite who deny life
to the primary around which they revolve. Such arguments support E. S.
Holden's statement that Herschel's views on solar and lunar life "rest
more on a metaphysical than a scientific basis. . . . "72
,Holden's conclusion, however, needs to be qualified in one important
way that helps explain why the premier astrollomer of that day adopted
such a strange theory. Although as early as 1780 Herschel had considered a form of this solar model (I, p. xcvi), he had between then and 1795
68
FROM 1750 TO 1800
accumulated astronomical evidences that, when viewed in terms of his
pluralist metaphysics, substantially increased the attractiveness of that
model. In particular, during this period Herschel's sidereal researches
had led him to observe what he describes in his 1795 solar paper as "very
compressed clusters of stars." He goes on to state concerning stars in
such cluster that
. . . it will hardly be possible to assign any sufficient mutual distance [to them]
to leave room for crowding in those planets, for whose support those stars have
beelt, or might be, supposed to exist. It would seem, therefore, highly probable
tha't they exist for themselves; and are, in fact, only very capital, lucid, primary
planets, connected together in one great system of mutual support. (1, pp, 482.-3)
Thus, Herschel had found a way to save these stars from being "mere
useless brilliant points" (I, p. 484), or, put differently, to rescue his
teleologically based pluralist metaphysics from a serious difficulty. That
Herschel's solar theory was no passing fancy in his thought is shown by
his having elaborated it further in an 1801 paper in which he refers to the
sun as "a most magnificent habitable globe" (11, p. 147) and by his 1814
description of stars as "so many opaque,habitable, planetary globes."
(II, p. 52.9) Moreover, although Agnes Clerke, writing in 1885, described
Herschel's solar model as more primitive than that of Anaxagoras, it
persisted as the preferred theory of the sun until the 18 50S. 73
Herschel's pluralist convictions did not extend to comets. This and
other interesting points ~re evident in extensive unpublished notes he
made in 1799 when he first encountered Lambert's Cosmologische
Briefe, reading it in J. B. Merian's French condensation. His published
description of Lambert's book as "full of the most fantastic imaginations" (II, p. 318) is expressed in more detail in these notes, a selection
from which follows, the numbers cited referring to the pages of Merian's
text:
2.4. Worlds in grains of sand, and inhabitan[t)s! This paragraph is too poetical to
be philosophical.
.
2.6. "We cannot make a step without destroying worlds and without creating new
ones I" What an abuse of words is this kind of language!
38. The author supposes "that fire may have its inhabitants." Very poetical!
60. The author seems to be perfectly in the secrets of the Creator. He makes as
many Celestial bodies as he can find room for. . . He tells us which is the most
perfect plan.
64. The author now is so fOl).d of his comets that he finds it necessary to apologize
for the existence of planets.
79. Now we also have traveling globes (or astronomers and th~.authors [sic] pity
for not being upon one of them.
140 • The auther [sic] now uses all the licence [sic] of the poets in the flights of
fancy. He confesses that it makes his head giddy, and that he does not know
where to stop. I do not call this Astronomy, but wild imagination.74
This selection, which includes all Herschel's notes on Lambert's plural-
ASTRONOMERS AND EXTRATERRESTRIALS
69
, . ism, is interesting also for what it does not contain, that is, any explicit
criticism of Lambert's extreme teleological approach. This suggests that
Herschel was not put off by Lambert's pluralism, but only by the form he
gave it. Although Herschel had observational reasons for rejecting Lambert's cometary inhabitants, his negative reaction to this idea was probably primarily due to the fact that in his own evolutionary cosmology he
had found another teleological justification for comets: as mechanisms
for the rejuvenation of stars (I, p. 478).
If one looks broadly at Herschel's career, at least three questions come
to mind that Herschel scholars have perhaps not fully answered. First,
what inspired him to forsake music for astronomy? It cannot have been a
desire to discover (as he did) a new planet; for weeks after detecting
Uranus he identified it as a comet. Nor was it a determination to become
(as he did) the founder of observational stellar astronomy; this field
scarcely existed in the early 1780S.'5 Second, what drove him to unparalleled efforts to build giant telescopes, the usefulness of which was
scarcely obvious in an age dominated by positional astronomy? As recent
research has shown, Herschel's scientific contemporaries at first viewed
both this stress on large telescopes and his overall conception of astronomy as peculiar. 76 Third, what led King George III not only to bestow an
annual salary on Herschel but also to lavish 4,000 pounds on the construction of a telescope of unprecedented size? The present analysis of
Herschel's extraterrestrial life ideas suggests a partly conjectural reconstruction of his career that may shed light on these questions. Herschel's
entry into astronomy can be attributed in good part to the appeal of the
pious pluralism present in the works of such authors as Ferguson. Captivated by Ferguson's claims for lunar life, Herschel boldly if naively
sought to detect it directly, being encouraged by his early, albeit ambiguous, observations. This hope fired his passion for improved telescopes,
for which he also found other uses. As the circle of his astronomical
associates widened, he learned that they looked askance at his extraterrestrial endeavors. Whether or not Herschel, after Maskelyne's rebuke,
shared his hope to detect lunar life with others besides Wilson is unclear,
but one can conjecture that the munificence of the monarch may have
been motivated by Herschel confiding to the king that his discovery of the
Georgian planet was only a prelude to a more dramatic discovery toward
which his progress had been halted by the inadequacies of his instruments. Such a secret conversation may have contributed to the king's
delusion, when beset in 1788 by mental illness, that he could see Hanover
through HerschePs telescopes. 77
This reconstruction is admittedly conjectural; what is certain is Herschel's lifelong commitment to ideas of extraterrestrial life. This firstled to
observational efforts but gradually gave way to what Simon Schaffer has
70
FROM 1750 TO 1800
described as "his relentless pursuit of the material conditions for extraterrestrial life. . . ."78 The theories Herschel developed in this later
quest, such as that of life on the sun, may ultimately have been no more
successful than his earlier endeavors. Nonetheless, they supplied encouragement to a generation or more of pluralists, including (as will be
shown) Herschel's brilliant son John. Lest this analysis of Herschel's
career be misunderstood, it is important to ask whether Herschel's extra~
terrestrial life ideas justify labeling him a "lunatic," as he feared MaskeIy~e might do. At a time when historians of science have demonstrated
the depth of Kepler's commitment to Pythagoreanism and Newton's
commitment to alchemy, such a label is certainly unsuitable. Herschel,
like Kepler and Newton, was a man of remarkable genius and a man of
his time. The legitimacy of the latter point will become more evident as
we encounter many other eighteenth-century intellectuals scarcely less
committed to pluralism than Herschel.