Bold text Intelligence is an umbrella term used to describe a property of the mind that encompasses many related abilities, such as the capacities to reason,to plan, to problem solving, to think abstractly, to comprehend ideas, to use language, and tolearn. There are several ways to define intelligence. In some cases, intelligence may include traits such as creativity,personality,character structure, knowledge, or wisdom. However, most psychologists prefer not to include these traits in the definition of intelligence.
Theories of intelligence can be divided into those based on a unilinear construct of general intelligence and those based on multiple intelligences. Francis Galton, influenced by his cousin Charles Darwin, was the first to advance a theory of general intelligence. For Galton, intelligence was a real faculty with a biological basis that could be studied by measuring reaction times to certain cognitive tasks. Galton's research on measuring the head size of British scientists and ordinary citizens led to the conclusion that head size had no relationship with the person's intelligence.
Alfred Binet and the French school of intelligence believed that intelligence was an average of numerous dissimilar abilities, rather than a unitary entity with specific identifiable properties. The Stanford-Binetintelligence test has been used by both theorists of general intelligence and multiple intelligence.
Intelligence comes from the Latin verb intellegere, which means "to understand". By this rationale, intelligence as understanding is arguably different from being "smart", able to adapt to one's environment. At least two major "consensus" definitions of intelligence have been proposed. First, from Intelligence: Knowns and Unknowns, a report of a task force convened by the American Psychological Association in 1995:
Individuals differ from one another in their ability to understand complex ideas, to adapt effectively to the environment, to learn from experience, to engage in various forms of reasoning, to overcome obstacles by taking thought. Although these individual differences can be substantial, they are never entirely consistent: a given person’s intellectual performance will vary on different occasions, in different domains, as judged by different criteria. Concepts of "intelligence" are attempts to clarify and organize this complex set of phenomena. Although considerable clarity has been achieved in some areas, no such conceptualization has yet answered all the important questions and none commands universal assent. Indeed, when two dozen prominent theorists were recently asked to define intelligence, they gave two dozen somewhat different definitions.
A second definition of intelligence comes from "Mainstream Science on Intelligence", which was signed by 52 intelligence researchers in 1994:
A very general mental capability that, among other things, involves the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly and learn from experience. It is not merely book learning, a narrow academic skill, or test-taking smarts. Rather, it reflects a broader and deeper capability for comprehending our surrounding;"catching on", "making sense" of things, or "figuring out" what to do.
Another simple and efficient definition is: the ability to apply knowledge in order to perform better in an environment.
Researchers in the fields of psychology and learning have also defined human intelligence:
Judgment, otherwise called good sense, practical sense, initiative, the faculty of adapting one's self to circumstances. The aggregate or global capacity of the individual to act purposefully, to think rationally, and to deal effectively with his environment. Innate general cognitive ability.
To my mind, a human intellectual competence must entail a set of skills of problem solving —enabling the individual to resolve genuine problems or difficulties that he or she encounters and, when appropriate, to create an effective product—and must also entail the potential for finding or creating problems—and thereby laying the groundwork for the acquisition of new knowledge.
The ability to deal with cognitive complexity,adaptive behavior.
A mathematical definition of "intelligence" using notions from computer science. Mathematical definitions have, as one advantage, that they could be applied to nonhuman intelligences and in the absence of human testers.
Theories of intelligence The most widely accepted theory of intelligence is based on psychometricstesting or intelligence quotient (IQ) tests. However, dissatisfaction with traditional IQ tests has led to the development of a number of alternative theories, all of which suggest that intelligence is the result of a number of independent abilities that uniquely contribute to human performance.
Psychometric approach, despite the variety of concepts of intelligence, the approach to understanding intelligence with the most supporters and published research over the longest period of time is based on psychometricstesting. Such intelligence quotient (IQ) tests include the Stanford-Binet, Raven's Progressive Matrices, the Wechsler Adult Intelligence Scaleand the Kaufman Assessment Battery for Children.
Intelligence, as measured by IQ and other aptitude tests, is widely used in educational, business, and military settings due to its efficacy in predicting behavior. is highly correlated with many important social outcomes - individuals with low IQs are more likely to be divorced, have a child out of marriage, be incarcerated, and need long term welfare support, while individuals with high IQs are associated with more years of education, higher status jobs and higher income.
IQ tests were originally designed to identify mentally "defective" children.
Critics of the psychometrics point out that intelligence is often more complex and broader in conception than what is measured by IQ tests. Furthermore, skeptics argue that even though tests of mental abilities are correlated, people still have unique strengths and weaknesses in specific areas. Consequently they argue that psychometric theorists over-emphasize .
Researchers in the field of human intelligence have encountered a considerable amount of public concern and criticism much more than scientists in other areas normally receive. A number of critics have challenged the relevance of psychometric intelligence in the context of everyday life. There have also been controversies over genetic factors in intelligence, particularly questions regarding the relationship between race and intelligence and sex and intelligence.
Intelligence is defined as an individual’s assessment of success in life by the individual’s own Nomothetic and idiographic standards and within the individual’s sociocultural context. Success is achieved by using combinations of analytical, creative, and practical intelligence. The three aspects of intelligence are referred to as processing skills. The processing skills are applied to the pursuit of success through what were the three elements of practical intelligence: adapting to, shaping of, and selecting of one’s environments. The mechanisms that employ the processing skills to achieve success include utilizing one’s strengths and compensating or correcting for one’s weaknesses.
Evolution of intelligence Our human ancestors evolved large and complex brains exhibiting an ever-increasing intelligence through a long and mostly unknown evolutionary process. This process was either driven by the direct adaptive benefits of intelligence.
Factors affecting intelligence Intelligence is an ill-defined, difficult to quantify concept. Accordingly, the IQ tests used to measure intelligence provide only approximations of the posited 'real' intelligence. In addition, a number of theoretically unrelated properties are known to correlate with IQ such as race, Sex and genderand height but since correlation does not imply causation the true relationship between these factors is uncertain. Factors affecting IQ may be divided into biological and environmental.
Biological Evidence suggests that genetic variation has a significant impact on IQ, accounting for three fourths in adults. Despite the high heritability of IQ, few genes have been found to have a substantial effect on IQ, suggesting that IQ is the product of interaction between multiple genes.
Other biological factors correlating with IQ include Neuroscience and Brain size ratio of brain weight to body weight and the Neurosciencevolume and location of gray matter tissue in the brain.
Because intelligence appears to be at least partly dependent on brain structure and the genes shaping brain development, it has been proposed that genetic engineering could be used to enhance the intelligence of animals, a process sometimes called biological uplift in science fiction.Experiments on mice have demonstrated superior ability in learning and memory in various behavioural tasks.
Environmental Evidence suggests that family environmental factors may have an effect upon childhood IQ, accounting for up to a quarter of the variance. On the other hand, by late adolescence this correlation disappears, such that adoptive siblings are no more similar in IQ than strangers. Moreover, adoption studies indicate that, by adulthood, adoptive siblings are no more similar in IQ than strangers, while twins and full siblings show an IQ correlation.
Consequently, in the context of the nature versus nurture debate, the "nature" component appears to be much more important than the "nurture" component in explaining IQ variance in the general population.
There are indications that, in middle age, intelligence is influenced by life style choices, long working hours.
Cultural factors also play a role in intelligence. For example, on a sorting task to measure intelligence, Westerners tend to take a taxonomic approach while the Kpelle people take a more functional approach. For example, instead of grouping food and tools into separate categories, a Kpelle participant stated "the knife goes with the orange because it cuts it"
Ethical Issues Since intelligence is susceptible to modification through the manipulation of environment, the ability to influence intelligence raises ethical issues. Transhumanist theorists study the possibilities and consequences of developing and using techniques to enhance human abilities and aptitudes, and ameliorate what it regards as undesirable and unnecessary aspects of the human condition; eugenics is a social philosophy which advocates the improvement of human hereditary traits through various forms of intervention. The perception of eugenics has varied throughout history, from a social responsibility required of society, to an immoral, racist stance.
Neuroethics considers the ethical, legal and social implications of neuroscience, and deals with issues such as difference between treating a human neurologicaldisease and enhancing the human brain, and how wealth impacts access to neurotechnology. Neuroethical issues interact with the ethics of human genetic engineering.
Although humans have been the primary focus of intelligence researchers, scientists have also attempted to investigate animal intelligence, or more broadly, animal cognition. These researchers are interested in studying both mental ability in a particular species, and comparing abilities between species. They study various measures of problem solving, as well as mathematical and language abilities. Some challenges in this area are defining intelligence so that it means the same thing across species (eg. comparing intelligence between literate humans and illiterate animals), and then operationalizing a measure that accurately compares mental ability across different species and contexts.
Cephalopod intelligence also provides important comparative study. Cephalopods appear to exhibit characteristics of significant intelligence, yet their nervous systems differ radically from those of most other notably intelligent life-forms mammals and birds.