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2003 First Paper
Human intelligence is an eel-like subject: slippery, difficult to grasp, and almost impossible to get straight . Many scientist and psychologist have made numerous attempts to come up with an explanation for the development of human intelligence. For many years, there has been much controversy over what intelligence is and whether it is hereditary or nurtured by the environment. Webster's dictionary defines intelligence as "the ability to acquire and apply knowledge; which includes a sensing an environment and reaching conclusions about the state of that environment . In this paper I am going to examine the factors, which make up ones intelligence. I will be investigating whether or not intelligence is fostered by genetic heritance or nurtured by ones environment.
"There can be of course no serious doubt that differences in environment experiences do contribute to variation in IQ . The environment is made of circumstances, objects, and conditions by which a human, animal, plant or object are surrounded in science. It has been argued that the environment in a child's developing years could in fact be a factor that will determine this IQ. In a study of adoptive and biologically related familys psychologist Scarr and Weinberg recognized that with children between 16 and 22 years of age, environment was more powerful in influencing IQ level in the young child, than the young adult. Scarr and Weinberg reasoned that "environment exerts a greater influence on children, who have little choice; as they age, diversity age, diversity and availability of choices expands, and if these choices are at least partially determined by genetic factors, the influence of environment is there by diminished.
Heritability is a term from the population of genetics. It refers to"the capability of being passed from one generation to the next . Intelligence has for centuries been considered as fixed trait. A number of investigators have taken an approach that intelligence is highly heritable, transmitted through genes . Kinship studies have shown that the habitability of IQ is significantly less than 1.0, and recent attempts to model kinship correlation especially in children have agreed that IQ is influenced both by the child's parent and the environment. Other factors such as parental affection, birth order, gender differences, and experiences outside the family, accidents, and illnesses may account for IQ.
Writer of Hereditary Genius, Francis Galton developed a theory know as the "genius theory." He thought human intelligence was hereditary under limitations that required to be investigated . He tried to distinguish between factors in several ways, culminating with his study of the life history the changes of twins, from which he concluded that the effect of nurture was very weak compared with that of nature. Continuing his investigation Galton measured resemblance between relatives; understanding of the genetic relatedness of monozygotic and dizygotic twins; and the accumulation of data on cross- fostered children and on twins raised apart , this allows the effect of heredity to be distinguished from that of shared family environment. This allowed Galton to conclude, "Education and the environment produce only a small effect on the mind of any one, and that most of our qualities are innate" .
The hereditability of intelligence has been an extremely controversial topic. In fact, it has been so notorious that it is difficult to pin point how intelligence is actually formed. There is no direct answer to whether or not intelligence is affected by ones environment or traits. As shown in this paper many scientist and psychologist have several different views on the formation of intelligence. Some believe that intelligence is affected by the environment; while others strongly believe that intelligence is hereditary. With further research, I hope to continue to explore the diversity of views surrounding the issue of intelligence. I also hope to come to a conclusion on whether or not intelligence is fostered by genetic inheritance or nurtured by the environment.
1) Cognitive Psychology and its Implications , interesting ways of learning
2) Hereditability and Intelligence, a rich resource on intelligence and heritability
3) IQ and Human Intelligence, investigations on intelligence, by N.J. Mackintosh
4) Memory miscalculation foils IQ
5) Flynn, J.R. "Trends over time: Intelligence, race, and meritocracy. Princeton University Press, 2000.
6) Galton, Francis. Hereditary Genius. London: Macmillan and Company, 1892.
Dictionary, an electronic dictionary
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