IO PSYCHOTHERAPY : SCIENTIFIC AND RELIGIOUS chap.
problem as a whole indicates that the conception of reason as the ultimate sanction in conduct is too idealistic. Rational eugenic programmes must suffer from the pessimism all of us feel when we reflect on the continued irrational behaviour of people.
Besides the efforts of the eugenists we have had the discoveries of the psychoanalysts who find the pattern of adult life has its origin in infancy and is already well established before puberty. Our habits of living, our ideals, even our affections are determined in their selection by early parental and fraternal relationships.
From the rediscovery of the Mendelian laws at the beginning of this century we have become better informed about heredity factors. For a short time the attempt was made to deal with personality traits from this angle, but it was soon realized that this aspect of human inheritance is infinitely more complex.
Even if our heritage was solely dependent upon the genes their number is so great that millions of combinations are possible. With a very few exceptions, therefore, the inherited characteristics are entirely unpredictable, and so many variables and unknown factors obtrude that the subject appears hopelessly involved.
The slow progress made in the study of heredity has had the effect not only of discouraging consistent effort in the field, but of giving the impression to those insufficiently informed that all such effort is futile. In spite of the prevailing emphasis on the influence of environment, a mass of evidence has accumulated which compels a closer evaluation of the influence of heredity.
The presence of musical talent in families is at least suggestive of influence of heredity.181 Exceptional musical ability has been traced for three or more generations in a large number of families. In the Bach family it is to be observed in unbroken line through five generations. In