Myths and Marvels of Astronomy
misapprehensions, were even more interesting to De Morgan than the
craftier sort who make a living, or try to make a living, out of their
pretended theories. Indeed, these last he treated, as they deserved,
with a scathing satire quite different from his humorous and not
ungenial comments on the wonderful theories of the honest paradoxists.
There is one special use to which the study of paradox-literature may be
applied, which--so far as I know--has not hitherto been much attended
to. It may be questioned whether half the strange notions into which
paradoxists fall must not be ascribed to the vagueness of too many of
our scientific treatises. A half-understood explanation, or a carelessly
worded account of some natural phenomenon, leads the paradoxist, whose
nature is compounded of conceit and simplicity, to originate a theory of
his own on the subject. Once such a theory has been devised, it takes
complete possession of the paradoxist's mind. All the facts of which he
thenceforward hears, which bear in the least on his favourite craze,
appear to give evidence in its favour, even though in reality they are
most obviously opposed to it. He learns to look upon himself as an
unappreciated Newton, and to see the bitterest malevolence in those who
venture to question his preposterous notions. He is fortunate if he do
not suffer his theories to withdraw him from his means of earning a
livelihood, or if he do not waste his substance in propounding and
defending them.
One of the favourite subjects for paradox-forming is the accepted theory
of the solar system. Our books on astronomy too often present this
theory in such sort that it seems only a _successor_ of Ptolemy's; and
the impression is conveyed that, like Ptolemy's, it may be one day
superseded by some other theory. This is quite enough for the
paradoxist. If a new theory is to replace the one now accepted, why
should not _he_ be the new Copernicus? He starts upon the road without a
tithe of the knowledge that old Ptolemy possessed, unaware of the
difficulties which Ptolemy met and dealt with--free, therefore, because
of his perfect ignorance, to form theories at which Ptolemy would have
smiled. He has probably heard of the
centrics and eccentrics scribbled o'er
Cycle and epicycle, orb in orb,
which disfigured the theories of the ancients; but he is quite
unconscious that every one of those scribblings had a real meaning, each
being intended to account for some observed peculiarity of planetary
motion, which _must_ be accounted for by any theory which is to claim
acceptance. In this happy unconsciousness that there are any
peculiarities requiring explanation, knowing nothing of the strange
paths which the planets are seen to follow on the heavenly vault,
Their wand'ring course now high, now low, then hid,
Progressive, retrograde, or standing still,
he placidly puts forward--and presently very vehemently urges--a theory
which accounts for none of these things.
It has often seemed to me that a large part of the mischief--for let it
be remembered that the published errors of the paradoxist are indicative
of much unpublished misapprehension--arises from the undeserved contempt
with which our books of astronomy too often treat the labours of
Ptolemy, Tycho Brahe, and others who advocated erroneous theories. If
the simple truth were told, that the theory of Ptolemy was a masterpiece
of ingenuity and that it was worked out by his followers in a way which
merits the highest possible praise, while the theory of Tycho Brahe was
placed in reality on a sounder basis than that of Copernicus, and
accounted as well and as simply for observed appearances, the student
would begin to realise the noble nature of the problem which those great
astronomers dealt with. And again, if stress were laid upon the fact
that Tycho Brahe devoted years upon years of his life to secure such
observations of the planets as might settle the questions at issue, the
student would learn something of the spirit in which the true lover of
science proceeds.
It seems to me, also, that far too little is said about the kind of work
by which Kepler and Newton finally established the accepted theories.
There is a strange charm in the history of those twenty years of
Kepler's life during which he was analysing the observations made by
Tycho Brahe. Surrounded with domestic trials and anxieties, which might
well have claimed his whole attention, tried grievously by ill-health
and bodily anguish, he laboured all those years upon erroneous theories.
The very worst of these had infinitely more evidence in its favour than
the best which the paradoxists have brought forth. There was not one of
those theories which nine out of ten of his scientific contemporaries
would not have accepted ungrudgingly. Yet he wrought these theories one
after another to their own disproof. _Nineteen_ of them he tried and
rejected--the twentieth was the true theory of the solar system. Perhaps
nothing in the whole history of astronomy affords a nobler lesson to the
student of science--unless, indeed, it be the calm philosophy with which
Newton for eighteen years suffered the theory of the universe to remain
in abeyance, because faulty measurements of the earth prevented his
calculations from agreeing with observed facts. But, as Professor
Tyndall has well remarked--and the paradoxist should lay the lesson
well to heart--'Newton's action in this matter was the normal action of
the scientific mind. If it were otherwise--if scientific men were not
accustomed to demand verification, if they were satisfied with the
imperfect while the perfect is attainable--their science, instead of
being, as it is, a fortress of adamant, would be a house of clay, ill
fitted to bear the buffetings of the theologic storms to which it has
been from time to time, and is at present, exposed.'
The fame of Newton has proved to many paradoxists an irresistible
attraction; it has been to these unfortunates as the candle to the
fluttering moth. Circle-squaring, as we shall presently see, has had its
attractions, nor have earth-fixing and earth-flattening been neglected;
but attacking the law of gravitation has been the favourite work of
paradoxists. Newton has been praised as surpassing the whole human race
in genius; mathematicians and astronomers have agreed to laud him as
unequalled; why should not Paradoxus displace him and be praised in like
manner? It would be unfair, perhaps, to say that the paradoxist
consciously argues thus. He doubtless in most instances convinces
himself that he has really detected some flaw in the theory of
gravitation. Yet it is impossible not to recognise, as the real motive
of every paradox-monger, the desire to have that said of him which has
been said of Newton: '_Genus humanum ingenio superavit._'
I remember a curious instance of this which occurred soon after the
appearance of the comet of 1858. It chanced that, while that object was
under discussion, reference was made to the action of a repulsive force
exerted by the sun upon the matter of the comet's tail. On this, some
one addressed a long letter to a Glasgow newspaper, announcing that he
had long ago proved that the sun's attraction alone is insufficient to
account for the planetary motions. His reasoning was amazingly simple.
If the sun's attraction is powerful enough to keep the outer planets in
their course, it must be too powerful for Venus and Mercury close by the
sun; if it only just suffices to keep these in their course, it cannot
possibly be powerful enough to restrain the outer planets. The writer of
this letter said that he had been very badly treated by scientific
bodies. He had announced his discovery to the Royal Astronomical
Society, the Royal Society, the Imperial Academy at Paris, and other
scientific bodies; but they had one and all refused to listen to him. He
had forsaken or neglected his trade for several years in order to give
attention to the new and (as he thought) the true theory of the
universe. He complained in a specially bitter manner of the unfavourable
comments which men of science had made upon his views in private letters
addressed to him in reply to his communications.
There is something melancholy even in what is most ridiculous in cases
of this sort. The simplicity which supposes that considerations so
obvious as those adduced could escape the scrutiny, not of Newton only,
but of all who have followed in the same track during two centuries, is
certainly stupendous; nor can one fail to smile at seeing a difficulty,
such as might naturally suggest itself to a beginner, and such as
half-a-dozen words from an expert would clear up, regarded gravely as a
discovery calculated to make its author famous for all time. Yet, when
one considers the probable consequences of the blunder to the unhappy
enthusiast, and perchance to his family, it is difficult not to feel a
sense of pity, quite apart from that pity allied to contempt which is
excited by his mistake. A few words added to the account of Newton's
theory, which the paradoxist had probably read in some astronomical
treatise, would have prevented all this mischief. Indeed, this
difficulty, which, as we have said, is a natural one, should be dealt
with and removed in any account of the planetary system intended for
beginners. The simple statement that the outer planets move more slowly
than the inner, and so _require_ a smaller force to keep them in their
course, would have sufficed, not, perhaps, altogether to remove the
difficulty, but to show the beginner where the explanation was to be
looked for.
It was in connection with this subject of gravitation that one of the
most well-meaning of the paradoxists--the late Mr. James Reddie--came
under Professor De Morgan's criticism. Mr. Reddie was something more
than well-meaning. He was earnestly desirous of advancing the interests
of science, as well as of defending religion from what he mistakenly
supposed to be the dangerous teachings of the Newtonians. He founded for
these purposes the Victoria Institute, of which society he was the
secretary from the time of its institution until his decease, some years
since; and, probably, many who declined to join that society because of
the Anti-Newtonian proclivities of its secretary, were unaware that to
that secretary the institute owed its existence.
It so chanced that I had myself a good deal of correspondence with Mr.
Reddie (who was, however, personally unknown to me). This correspondence
served to throw quite a new light on the mental habitudes and ways of
thinking of the honest paradoxist. I believe that Professor De Morgan
hardly gave Mr. Reddie credit for the perfect honesty which he really
possessed. It may have been that a clear reasoner like De Morgan could
hardly (despite his wide experience) appreciate the confusion of mind
which is the normal characteristic of the paradoxist. But certainly the
very candid way in which Mr. Reddie admitted, in the correspondence
above named, that he had not known some facts and had misunderstood
others, afforded to my mind the most satisfactory proofs of his
straightforwardness.
It may be instructive to consider a few of those paradoxes of Mr.
Reddie's which Professor De Morgan found chief occasion to pulverise.
In a letter to the Astronomer-Royal Mr. Reddie announced that he was
about to write 'a paper intended to be hereafter published, elaborating
more minutely and discussing more rigidly than before the glaring
fallacies, dating from the time of Newton, relating to the motion of the
moon.' He proceeded to 'indicate the nature of the issues he intended to
raise.' He had discovered that the moon does not, as a matter of fact,
go round the earth at the rate of 2288 miles an hour, as astronomers