I knew them, for a period of two years, there was not the slightest
tendency towards a difference in body or mind; external influences
seemed powerless to produce any dissimilarity." The mother of two other
twins, after describing how they were ill simultaneously up to the age
of fifteen, adds, that they shed their first milk teeth within a few
hours of each other.
Trousseau has a very remarkable case (in the chapter on Asthma) in his
important work, "Clinique Médicale." It was quoted at length in the
original French in Mr. Darwin's "Variation Under Domestication," vol.
ii. p. 252. The following is a translation:
"I attended twin brothers so extraordinarily alike, that it was
impossible for me to tell which was which without seeing them side by
side. But their physical likeness extended still deeper for they had, so
to speak, a yet more remarkable pathological resemblance. Thus, one of
them, whom I saw at the Néothermes at Paris, suffering from rheumatic
ophthalmia, said to me, 'At this instant, my brother must be having an
ophthalmia like mine;' and, as I had exclaimed against such an
assertion, he showed me a few days afterwards a letter just received by
him from his brother, who was at that time at Vienna, and who expressed
himself in these words: 'I have my ophthalmia; you must be having
yours.' However singular this story may appear, the fact is none the
less exact: it has not been told to me by others, but I have seen it
myself; and I have seen other analogous cases in my practice. These
twins were also asthmatic, and asthmatic to a frightful degree. Though
born in Marseilles, they never were able to stay in that town, where
their business affairs required them to go, without having an attack.
Still more strange, it was sufficient for them to get away only as far
as Toulon in order to be cured of the attack caught at Marseilles. They
travelled continually, and in all countries, on business affairs, and
they remarked that certain localities were extremely hurtful to them,
and that in others they were free from all asthmatic symptoms."
I do not like to pass over here a most dramatic tale in the _Psychologie
Morbide_ of Dr. J. Moreau (de Tours), Médecin de l'Hospice de Bicetre.
Paris, 1859, p. 172. He speaks "of two twin brothers who had been
confined, on account of monomania, at Bicetre.... Physically the two
young men are so nearly alike that the one is easily mistaken for the
other. Morally, their resemblance is no less complete, and is most
remarkable in its details. Thus, their dominant ideas are absolutely the
same. They both consider themselves subject to imaginary persecutions;
the same enemies have sworn their destruction, and employ the same means
to effect it. Both have hallucinations of hearing. They are both of them
melancholy and morose; they never address a word to anybody, and will
hardly answer the questions that others address to them. They always
keep apart and never communicate with one another. An extremely curious
fact which has been frequently noted by the superintendents of their
section of the hospital, and by myself, is this: From time to time, at
very irregular intervals of two, three, and many months, without
appreciable cause, and by the purely spontaneous effect of their
illness, a very marked change takes place in the condition of the two
brothers. Both of them, at the same time, and often on the same day,
rouse themselves from their habitual stupor and prostration; they make
the same complaints, and they come of their own accord to the physician,
with an urgent request to be liberated. I have seen this strange thing
occur, even when they were some miles apart, the one being at Bicetre
and the other living at Sainte-Anne."
Dr. Moreau ranked as a very considerable medical authority, but I cannot
wholly accept this strange story without fuller information. Dr. Moreau
writes it in too off-hand a way to carry the conviction that he had
investigated the circumstances with the sceptic spirit and scrupulous
exactness which so strange a phenomenon would have required. If full and
precise notes of the case exist, they certainly ought to be published at
length. I sent a copy of this passage to the principal authorities among
the physicians to the insane in England, asking if they had ever
witnessed any similar case. In reply, I have received three noteworthy
instances, but none to be compared in their exact parallelism with that
just given. The details of these three cases are painful, and it is not
necessary to my general purpose that I should further allude to them.
There is another curious French case of insanity in twins, which was
pointed out to me by Professor Paget, described by Dr. Baume in the
_Annales Medico-Psychologiques_, 4 série, vol. i., 1863, p. 312, of
which the following is an abstract. The original contains a few more
details, but it is too long to quote: Francois and Martin, fifty years
of age, worked as railroad contractors between Quimper and Châteaulin.
Martin had twice had slight attacks of insanity. On January 15, a box in
which the twins deposited their savings was robbed. On the night of
January 23-4 both Francois (who lodged at Quimper) and Martin (who lived
with his wife and children at St. Lorette, two leagues from Quimper) had
the same dream at the same hour, three A. M., and both awoke with a
violent start, calling out, "I have caught the thief! I have caught the
thief! they are doing injury to my brother!" They were both of them
extremely agitated, and gave way to similar extravagances, dancing and
leaping. Martin sprang on his grandchild, declaring that he was the
thief, and would have strangled him if he had not been prevented: he
then became steadily worse, complained of violent pains in his head,
went out of doors on some excuse, and tried to drown himself in the
River Steir, but was forcibly stopped by his son, who had watched and
followed him. He was then taken to an asylum by gendarmes, where he died
in three days. Francois, on his part calmed down on the morning of the
24th, and employed the day in enquiring about the robbery. By a strange
chance he crossed his brother's path at the moment when the latter was
struggling with the gendarmes; then he himself became maddened, giving
way to extravagant gestures and making incoherent proposals (similar to
those of his brother). He then asked to be bled, which was done, and
afterwards, declaring himself to be better, went out on the pretext of
executing some commission, but really to drown himself in the River
Steir, which he actually did, at the very spot where Martin had
attempted to do the same thing a few hours previously.
The next point which I shall mention, in illustration of the extremely
close resemblance between certain twins, is the similarity in the
association of their ideas. No less than eleven out of the thirty-five
cases testify to this. They make the same remarks on the same occasion,
begin singing the same song at the same moment, and so on; or one would
commence a sentence, and the other would finish it. An observant friend
graphically described to me the effect produced on her by two such twins
whom she had met casually. She said: "Their teeth grew alike, they spoke
alike and together, and said the same things, and seemed just like one
person." One of the most curious anecdotes that I have received
concerning this similarity of ideas was that one twin A, who happened to
be at a town in Scotland, bought a set of champagne glasses which caught
his attention, as a surprise for his brother B; while at the same time,
B, being in England, bought a similar set of precisely the same pattern
as a surprise for A. Other anecdotes of a like kind have reached me
about these twins.
The last point to which I shall allude regards the tastes and
dispositions of the thirty-five pairs of twins. In sixteen cases--that
is, in nearly one half of them--these were described as closely similar;
in the remaining nineteen they were much alike, but subject to certain
named differences. These differences belonged almost wholly to such
groups of qualities as these: The one was the more vigorous, fearless,
energetic; the other was gentle, clinging, and timid: or, again, the one
was more ardent, the other more calm and gentle; or again, the one was
the more independent, original, and self-contained; the other the more
generous, hasty, and vivacious. In short the difference was always that
of intensity or energy in one or other of its protean forms: it did not
extend more deeply into the structure of the characters. The more
vivacious might be subdued by ill health, until he assumed the character
of the other; or the latter might be raised by excellent health to that
of the former. The difference is in the key-note, not in the melody.
It follows from what has been said concerning the similar dispositions
of the twins, the similarity in the associations of their ideas, of
their special ailments, and of their illnesses generally, that the
resemblances are not superficial, but extremely intimate. I have only
two cases altogether of a strong bodily resemblance being accompanied by
mental diversity, and one case only of the converse kind. It must be
remembered that the conditions which govern extreme likeness between
twins are not the same as those between ordinary brothers and sisters (I
may have hereafter to write further about this); and that it would be
wholly incorrect to generalize from what has just been said about the
twins, that mental and bodily likeness are invariably co-ordinate; such
being by no means the case.
We are now in a position to understand that the phrase "close
similarity" is no exaggeration, and to realize the value of the evidence
about to be adduced. Here are thirty-five cases of twins who were
"closely alike" in body and mind when they were young, and who have been
reared exactly alike up to their early manhood and womanhood. Since then
the conditions of their lives have changed; what change of conditions
has produced the most variation?
It was with no little interest that I searched the records of the
thirty-five cases for an answer; and they gave an answer that was not
altogether direct, but it was very distinct, and not at all what I had
expected. They showed me that in some cases the resemblance of body and
mind had continued unaltered up to old age, notwithstanding very
different conditions of life; and they showed in the other cases that
the parents ascribed such dissimilarity as there was wholly, or almost
wholly, to some form of illness. In four cases it was scarlet fever; in
one case, typhus; in one, a slight effect was ascribed to a nervous
fever: then I find effects from an Indian climate; from an illness
(unnamed) of nine months' duration; from varicose veins; from a bad
fracture of the leg, which prevented all active exercise afterwards; and
there were three other cases of ill health. It will be sufficient to
quote one of the returns; in this the father writes:
"At birth they were _exactly_ alike, except that one was born with a bad
varicose affection, the effect of which had been to prevent any violent
exercise, such as dancing, or running, and, as she has grown older, to
make her more serious and thoughtful. Had it not been for this
infirmity, I think the two would have been as exactly alike as it is
possible for two women to be, both mentally and physically; even now
they are constantly mistaken for one another."
In only a very few cases is there some allusion to the dissimilarity
being partly due to the combined action of many small influences, and in
no case is it largely, much less wholly, ascribed to that cause. In not
a single instance have I met with a word about the growing dissimilarity
being due to the action of the firm, free will of one or both of the
twins, which had triumphed over natural tendencies; and yet a large
proportion of my correspondents happen to be clergymen whose bent of
mind is opposed, as I feel assured from the tone of their letters, to a
necessitarian view of life.
It has been remarked that a growing diversity between twins may be
ascribed to the tardy development of naturally diverse qualities; but we
have a right, upon the evidence I have received, to go further than
this. We have seen that a few twins retain their close resemblance
through life; in other words, instances do exist of thorough similarity
of nature, and in these external circumstances do not create
dissimilarity. Therefore, in those cases, where there is a growing
diversity, and where no external cause can be assigned either by the
twins themselves or by their family for it, we may feel sure that it
must be chiefly or altogether due to a want of thorough similarity in
their nature. Nay further, in some cases it is distinctly affirmed that
the growing dissimilarity can be accounted for in no other way. We may
therefore broadly conclude that the only circumstance, within the range
of those by which persons of similar conditions of life are affected,
capable of producing a marked effect on the character of adults, is
illness or some accident which causes physical infirmity. The twins who
closely resembled each other in childhood and early youth, and were
reared under not very dissimilar conditions, either grow unlike through
the development of natural characteristics which had lain dormant at
first, or else they continue their lives, keeping time like two watches,
hardly to be thrown out of accord except by some physical jar. Nature is
far stronger than nurture within the limited range that I have been
careful to assign to the latter.
The effect of illness, as shown by these replies, is great, and well
deserves further consideration. It appears that the constitution of
youth is not so elastic as we are apt to think, but that an attack, say
of scarlet fever, leaves a permanent mark, easily to be measured by the
present method of comparison. This recalls an impression made strongly
on my mind several years ago by the sight of a few curves drawn by a
mathematical friend. He took monthly measurements of the circumference
of his children's heads during the first few years of their lives, and
he laid down the successive measurements on the successive lines of a
piece of ruled paper, by taking the edge of the paper as a base. He then
joined the free ends of the lines, and so obtained a curve of growth.
These curves had, on the whole, that regularity of sweep that might have
been expected, but each of them showed occasional halts, like the
landing places on a long flight of stairs. The development had been
arrested by something, and was not made up for by after growth. Now, on
the same piece of paper my friend had also registered the various
infantile illnesses of the children, and corresponding to each illness
was one of these halts. There remained no doubt in my mind that, if
these illnesses had been warped off, the development of the children
would have been increased by almost the precise amount lost in these
halts. In other words, the disease had drawn largely upon the capital,
and not only on the income, of their constitutions. I hope these remarks
may induce some men of science to repeat similar experiments on their
children of the future. They may compress two years of a child's history
on one side of a ruled half-sheet of foolscap paper if they cause each
successive line to stand for a successive month, beginning from the
birth of the child; and if they mark off the measurements by laying, not
the 0-inch division of the tape against the edge of the pages, but, say,
the 10-inch division--in order to economize space.
The steady and pitiless march of the hidden weaknesses in our
constitutions, through illness to death, is painfully revealed by these
histories of twins. We are too apt to look upon illness and death as
capricious events, and there are some who ascribe them to the direct
effect of supernatural interference, whereas the fact of the maladies of
two twins being continually alike, shows that illness and death are
necessary incidents in a regular sequence of constitutional changes,
beginning at birth, upon which external circumstances have, on the
whole, very small effect. In cases where the maladies of the twins are
continually alike, the clock of life moves regularly on, governed by
internal mechanism. When the hand approaches the hour mark, there is a
sudden click, followed by a whirling of wheels; at the culminating
moment, the stroke falls. Necessitarians may derive new arguments from
the life histories of twins.
We will now consider the converse side of our subject. Hitherto we have
investigated cases where the similarity at first was close, but
afterwards became less: now we will examine those in which there was
great dissimilarity at first, and will see how far an identity of
nurture in childhood and youth tended to assimilate them. As has been
already mentioned, there is a large proportion of cases of sharply
contrasted characteristics, both of body and mind, among twins. I have
twenty such cases, given with much detail. It is a fact, that extreme
dissimilarity, such as existed between Esau and Jacob, is a no less
marked peculiarity in twins of the same sex, than extreme similarity. On
this curious point, and on much else in the history of twins, I have
many remarks to make, but this is not the place to make them.
The evidence given by the twenty cases above mentioned is absolutely
accordant, so that the character of the whole may be exactly conveyed by
two or three quotations. One parent says: "They have had _exactly the
same nurture_ from their birth up to the present time; they are both
perfectly healthy and strong, yet they are otherwise as dissimilar as
two boys could be, physically, mentally, and in their emotional
nature." Here is another case: "I can answer most decidedly that the
twins have been perfectly dissimilar in character, habits, and likeness
from the moment of their birth to the present time, though they were
nursed by the same woman, went to school together, and were never
separated till the age of fifteen." Here again is one more, in which the
father remarks: "They were curiously different in body and mind from
their birth." The surviving twin (a senior wrangler of Cambridge) adds:
"A fact struck all our school contemporaries, that my brother and I were
complementary, so to speak, in point of ability and disposition. He was
contemplative, poetical, and literary to a remarkable degree, showing
great power in that line. I was practical, mathematical, and linguistic.
Between us we should have made a very decent sort of a man." I could
quote others just as strong as these, while I have not a single case in
which my correspondents speak of originally dissimilar characters having
become assimilated through identity of nurture. The impression that all
this evidence leaves on the mind is one of some wonder whether nurture
can do anything at all beyond giving instruction and professional
training. It emphatically corroborates and goes far beyond the
conclusions to which we had already been driven by the cases of
similarity. In these, the causes of divergence began to act about the
period of adult life, when the characters had become somewhat fixed; but
here the causes conducive to assimilation began to act from the
earliest moment of the existence of the twins, when the disposition was
most pliant, and they were continuous until the period of adult life.
There is no escape from the conclusion that nature prevails enormously
over nurture when the differences of nurture do not exceed what is
commonly to be found among persons of the same rank of society and in
the same country. My only fear is that my evidence seems to prove too
much and may be discredited on that account, as it seems contrary to all
experience that nurture should go for little. But experience is often
fallacious in ascribing great effects to trifling circumstances. Many a
person has amused himself with throwing bits of stick into a tiny brook
and watching their progress; how they are arrested, first by one chance
obstacle, then by another; and again, how their onward course is
facilitated by a combination of circumstances. He might ascribe much
importance to each of these events, and think how largely the destiny of
the stick has been governed by a series of trifling accidents.
Nevertheless all the sticks succeed in passing down the current, and
they travel, in the long run, at nearly the same rate. So it is with
life in respect to the several accidents which seem to have had a great
effect upon our careers. The one element, which varies in different
individuals, but is constant in each of them, is the natural tendency;
it corresponds to the current in the stream, and invariably asserts
itself. More might be added on this matter, and much might be said in
qualification of the broad conclusions to which we have arrived, as to
the points in which education appears to create the most permanent
effect; how far by training the intellect and how far by subjecting the
boy to a higher or lower tone of public opinion; but this is foreign to
my immediate object. The latter has been to show broadly, and, I trust,
convincingly, that statistical estimation of natural gifts by a
comparison of successes in life, is not open to the objection stated at
the beginning of this memoir. We have only to take reasonable care in
selecting our statistics, and then we may safely ignore the many small
differences in nurture which are sure to have characterized each
individual case.
SIGHT IN SAVAGES
From "Idle Days in Patagonia"
WILLIAM HENRY HUDSON
[William Henry Hudson was born and for many years resided in
Patagonia. His "The Naturalist in La Plata" and "Idle Days in
Patagonia," both published by J. M. Dent & Co., London, and
D. Appleton & Co., New York, are among the most delightful
books of natural history ever written.]
A person much given to card-playing once informed me that always after
the first few rounds of a game he knew some of the cards in the pack,
and could recognize them as they were being dealt out, by means of
certain slight shades of difference in the colouring of the backs. He
had turned his attention to this business when very young, and as he was
close upon fifty when he imparted this interesting piece of information,
and had always existed comfortably on his winnings, I saw no reason to
disbelieve what he told me. Yet this very man, whose vision was keen
enough to detect differences in cards so slight that another could not
see them, even when pointed out--this preternaturally sharp-eyed
individual was greatly surprised when I explained to him that
half a dozen birds of the sparrow kind, that fed in his courtyard, and
sang and built their nests in his garden and vineyard and fields, were
not one but six distinct species. He had never seen any difference in
them: they all had the same customs, the same motions; in size, colour,
and shape they were all one; to his hearing they all chirped and
twittered alike, and warbled the same song.
And as it was with this man, so, to some extent, it is with all of us.
That special thing which interests us, and in which we find our profit
or pleasure, we see very distinctly, and our memories are singularly
tenacious of its image; while other things, in which we take only a
general interest, or which are nothing to us, are not seen so sharply,
and soon become blurred in memory; and if there happens to be a pretty
close resemblance in several of them, as in the case of my gambling
friend's half a dozen sparrows, which, like snowflakes, were "seen
rather than distinguished," this indistinctness of their images on the
eye and the mind causes them all to appear alike. We have, as it were,
two visions--one to which all objects appear vividly and close to us,
and are permanently photographed on the mind; the other which sees
things at a distance, and with that indistinctness of outline and
uniformity of colour which distance gives.