According to Pinter (1931) ‘The potency of environment is not merely so great as commonly supposed. A child’s abilities are determined by his ancestors and all that the environment can do is to give the opportunity for the development of his potentialities”. We can claim our calculations agree perfectly with the hypothesis that intelligence is inherited in the same way as physical characteristics are inherited.
Thus heredity is more important than environment in growth and development. Several experiment findings also emphasize importance of heredity in individual differences. Pearson (1904) found a remarkable resemblance among members of the same family in color of eyes, ratio of width and length of head and the physical traits which are by and large affected by environmental influences. Interestingly, he noted that the effect of heredity upon mental characteristics is the same as upon physical characteristics.
Contribution of Environment to child’s development: The effect of changed environment upon mental traits – two studies concluded by Chicago University group headed by Freeman (1925) and Stanford University group headed by Burks (1928) are notable. Both these investigations emphasized some what different methods, through the purpose was same i.e., to study the influence of home environment upon the development of mental traits in children. Freeman agrees with Burk’s view that heredity is a force in the determination of mental ability by the side of which all other forces are dwarfed in comparison. Both the studies agree upon the influence of heredity in shaping mental ability.
Both the groups show a general agreement on the role of environment in the development of individual intelligence. But the Chicago group seems to give greater emphasis to environment than to heredity. Watson has strongly emphasized the importance of environment in the development of human personality. If an individual’s abilities, efficiency and traits of personality would have bears exclusively influenced by genetic factors, environment, training and learning would have no value. Similarly, if training and education is considered as a sole factor influencing personality differences then favorable environmental opportunities are everything and potentialities and gifted qualities have no implications for personality development.
It seems more reasonable to say that both nature and nurture, heredity and environment have important roles to pay in the development of human being. But their relative importance differs in the development of various traits of personality.
Similarly, environment has the upper hand in the development of personality traits like sociability, amiability, honest, dominance, submission, introversion-extroversion, interests and several others socially desirable, undesirable traits. Regarding the mental activities, there are sufficient evidences to believe that heredity factors determine the potential level of physiological limit of development which an individual achieves at the maximum. Within this limit, the environment factors influence the level of development that really occurs.
Hence, neither nature nor nurture alone can explain one’s personality development. Heredity and Environment cooperatively and coordinately help in the growth and development of child’s behavior and personality.