Applied Eugenics | Page 6

a father who was a twin, remarks of himself and his brother:
"'We were extremely alike, and are so at this moment, so much so that our children up to five and six years old did not know us apart.'
"Among my thirty-five detailed cases of close similarity, there are no less than seven in which both twins suffered from some special ailment or had some exceptional peculiarity. Both twins are apt to sicken at the same time in no less than nine out of the thirty-five cases. Either their illnesses, to which I refer, were non-contagious, or, if contagious, the twins caught them simultaneously; they did not catch them the one from the other."
Similarity in association of ideas, in tastes and habits was equally close. In short, their resemblances were not superficial, but extremely intimate, both in mind and body, while they were young; they were reared almost exactly alike up to their early manhood and womanhood.
Then they separated into different walks of life. Did this change of the environment alter their inborn character? For the detailed evidence, one should consult Galton's own account; we give only his conclusions:
In many cases the resemblance of body and mind continued unaltered up to old age, notwithstanding very different conditions of life; in others a severe disease was sufficient to account for some change noticed. Other dissimilarity that developed, Galton had reason to believe, was due to the development of inborn characters that appeared late in life. He therefore felt justified in broadly concluding "that the only circumstance, within the range of those by which persons of similar conditions of life are affected, that is 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 [that is, inherited] 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."
Here was a distinct failure of nurture to modify the inborn nature. We next consider the ordinary twins who were unlike from the start. Galton had twenty such cases, given with much detail. "It is a fact," he observes, "that extreme dissimilarity, such as existed between Jacob and Esau, is a no less marked peculiarity of twins of the same sex than extreme similarity." The character of the evidence as a whole may be fairly conveyed by a few quotations:
(1) 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."
(2) "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 until the age of thirteen."
(3) "They have never been separated, never the least differently treated in food, clothing, or education; both teethed at the same time, both had measles, whooping cough, and scarlatina at the same time, and neither has had any other serious illness. Both are and have been exceedingly healthy, and have good abilities; yet they differ as much from each other in mental cast as any one of my family differs from another."
(4) "Very dissimilar in mind and body; the one is quiet, retiring, and slow but sure; good-tempered, but disposed to be sulky when provoked;--the other is quick, vivacious, forward, acquiring easily and forgetting soon; quick-tempered and choleric, but quickly forgiving and forgetting. They have been educated together and never separated."
(5) "They were never alike either in mind or body, and their dissimilarity increases daily. The external influences have been identical; they have never been separated."
(6) "The two sisters are very different in ability and disposition. The one is retiring, but firm and determined; she has no taste for music or drawing. The other is of an active, excitable temperament; she displays an unusual amount of quickness and talent, and is passionately fond of music and drawing. From infancy, they have been rarely separated even at school, and as children visiting their friends, they always went together."
And so on. Not a single case was found in which originally dissimilar characters became assimilated, although submitted to exactly the same influences. Reviewing the evidence in his usual cautious way, Galton declared, "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