Alfred Binet define intelligence as judgment , otherwise called “good sense” “practical sense” “initiative”, the faculty of adapting one’s self to circumstance… auto –critique.
Legg &Hutter define intelligence as a synthesis of 70+ definitions from psychology, and Al researcher. “Intelligence measures an agent’s ability to achieve goals in a wide range of environments, which has been mathematically formalized.
Intelligence has been defined in many different ways including one’s   capacity for logic, abstract thought, understanding, self –awareness, communication, learning, emotional knowledge, memor0py, planning, creativity and problem solving. It can be more generally describe as the ability to perceive information, and retain it as knowledge to be applied towards adaptive behaviors within an environment.
Intelligence derives from the Latin verb, intelligere, to comprehend or perceive. A form of this verb, intellectus became the medieval technical term for understanding, and a translation for the Greek philosophical terms nous. This term was however strongly linked to the metaphysical and cosmological theories of teleological scholasticism, including theories of the immorality of the soul, and the concept of the Active intellect (also known as the Active intelligence). This entire approach to the study of nature was strongly rejected by the early modern philosopher such as Francis Bacon, Thomas Hobbes, John Locke, and David Hume, all of whom preferred the word “understanding in their English philosophy, but it has later been taken up (with the scholastics theories which it now implies in more contemporary psychological

Human Intelligence is the intellectual capacity of humans, which is characterized by perception, consciousness, self –awareness, and volition. Through their intelligence, humans possess the cognitive abilities to learn, form concepts, understand, apply logic and reason, including the capacities to recognize patterns comprehend ideas plan, problem solve make decisions, retain information , and use language to communicate. Intelligence enables humans to experience and think.
There is no universally accepted definition of intelligence, one definition is the “ability to reason plan, solve problems think abstractly, comprehend ideas and language and learn”. The evolution of hominid intelligence can be traced over its course for the past 10 million years and attributed to specific environmental challenges.
It is a misunderstanding of evolutionary theory, however to see this as a necessary process, and an even greater misunderstanding to see it as one directed to a particular outcome.
There are primate species which have not evolved any greater degree of intelligence than they had 10 million years ago this is because their particular environment has not demanded this particular adaptation of them
Intelligence as adaption to the challenge of natural selection is no better no worse than any other adaptation, such as the speed of the cheetan or the venomous bite of the lebra. It is however, the only adaptation which has allowed a species to establish complete domination over the rest of the natural world, whether our species has yet acquired sufficient intelligent to image this responsibility is a matter for debate.
Theories of intelligence as is the case with most scientific theories, have evolved through a succession of models four of the most influential paradigms have been psychological measurement, also known as a psychometric, cognitive psychology which concerns itself with the process by which the mid functions, Cognitivism and Contextualism a combined approach that studies the interaction between the environment  and mental process and biological science which consider the neural bases of intelligence. What follows is a discussion of development within these four areas.


Psychometric theories are based on a model that portrays intelligence as a composite of abilities measured by mental test. This model can be quantified. For example, performance on a number series test might represent a weighted composite of number, reasoning and memory abilities for a complex series. Mathematical models allow for weakness in one area to be offset by strong ability. In another area of test performance in this way, superior ability in reasoning can compensate for a deficiency in a number ability.
One of the earliest of the psychometric theories came from the British psychologist Charles E. Spearman who published is first major articles in intelligence. He noticed what may seem obvious now that people who did on metal-ability test tended to do well on others, while people who performed poorly on one them also tended to perform poorly on others.


During the era dominated by psychometric theories, the study of intelligence was influced most by those investigating of intelligence was influced most by those investigating individual different in people’s test scores. In an address to the American Psychological Association, the American researcher lee croncbach, a leader in the testing field, decried the lack of common ground between psychologists who studied individual difference and those who studied commonalities in human behavior. Cronbach’s plea to unite “two discipline of scientific psychology” led in part to the development of cognitive theories.
Fair assement of performance require an understanding of the process underlying intelligence, otherwise there is a risk of arriving at conclusions that are misleading. If not simply wrong when evaluating overall test scores or other assement of performance. Suppose for example that a student performs poorly on the verb analogies question in a psychometric test. One possible solution conclusion is that the student does not understand the words or is unable to read them in the first place. A student who fails to solve the analogy ‘audacious is to pusillanimous as mitigate is to might be an excellent reasoner but have only a modest vocabulary, or vice vera. By using cognitive analysis the test interpreter is able to determine the degree for which the poor score stems from low reasoning ability and the degree to which it results from net understanding the words.

 The theories discussed above seek to understand intelligence in terms of hypothetical mental constructs, whether there are factors, cognitive processes or cognitive process in interaction with context. Biological theories represent a radically different approach that dispense with mental construct altogether. Adureate of such theories, usually called reductionists, believe that a true Understanding intelligence is possible only be identifying its biological basis. Some world argue that there is no alternative to reductionism if in fact the god is to explain rather than merely to describe behavior, But the case is not an open and shut one especially if intelligence is viewed as something more than the mere processing of information As Howard Gardner pointedly asked in the article “What we do and Don’t know About learning” [2004].    

Intelligence is broken down into nine different types, also called the nine domains of intelligence. This categorization of intelligence was first theorized by developmental psychologist.
Howard Gardner in his book Frames of mind: The Theory of Multiple intelligences. Since then, the Multiple Intelligences theory been used that has gone on concerning human cognition. Gardner argues that there is no true way to measure intelligence and that the human brain is wired with a wide range of cognitive abilities. Framing intelligence in the way Gardner does disrupts the old mold of thinking in which intelligence was ultimately a measure of (what Gardner would call) Logical mathematical intelligence. The premise of Gardner’s theory is that someone can be extremely bad at math yet be the best of the best in another field, such as music. Thus limiting the definition of intelligence is detrimental to our understanding of how the human brain works. So without further ado, I present to you the nine different types of intelligence:
Naturalist Intelligence
Ever wonder why certain people are able to connect with animals just like that? Have you ever encountered someone that possess what is commonly referred to as a “green thumb” Well, those people are great examples of “nature’s different features such as animals, plants, rock configurations, cloud formation and other such things. Today naturalistic intelligence remains a vital component of roles like being a chef or botanist.
Musical Intelligence
Musical intelligence is the capacity to discern pitch, rhyme, timbre and tone. This intelligence enables us to recognize, create, reproduce, and reflect on music as demonstrated by composers, conductors, musicians, vocalist and sensitive listeners. Interestingly, there is often an affective connection between music and the emotions; and mathematical and musical intelligence may share common thinking processes.
Logical-Mathematical Intelligence
Logical-mathematical intelligence is the ability to calculate, quantify, consider propositions and hypotheses, and carry out complete mathematical operations. It enables us to perceive relationships and connections and to use abstract, symbolic thought; sequential reasoning skills and inductive and deductive thinking patterns. Logical intelligence is usually well developed in mathematicians, scientists and detectives
Existential Intelligence
Sensitivity and capacity to tackle deep questions about human existence, such as the meaning of life, why do we die, and how did we get here.
Interpersonal Intelligence
Interpersonal Intelligence is the ability to understand and interact effectively with others. It involves effective verbal and nonverbal communication, the ability to note distinctions among others, sensitivity to the moods and temperaments of others, and the ability to entertain multiple perspectives. Teachers, social workers, actors and politicians all exhibit interpersonal intelligence.
Bodily-Kinesthetic Intelligence
Bodily kinesthetic intelligence is the capacity to manipulate objects and use a variety of physical skills. This intelligence also involves a sense of timing and perfection of skills through mind body union. Athletes, dancers, surgeons and craftspeople exhibit well developed bodily kinesthetic intelligences.
Linguistic Intelligence
Linguistic intelligence is the ability to think in words and to use language to express and appreciate complex meanings. Linguistic intelligence allows us to understand the order and meaning of words and to apply meta- linguistic skills to reflect on our use of language.
Intra-personal intelligence
Intra-personal intelligence is the capacity to understand oneself and one’s thoughts and feelings, and to use such knowledge in planning and directioning one’s life. Intra- personal intelligence involves not only an appreciation of the self, but also of the human condition. It is evident in psychologist, spiritual leaders and philosophers
Spatial Intelligence
Spatial intelligence is the ability to think in three dimensions. Core capacities include mental imagery, spatial reasoning, image manipulation, graphic and artistic skills and an active imagination. Sailors pilots, sculptors, painters and architect all exhibit spatial intelligence

                                                DEFINE IQ
An Intelligence quotient (IQ) is a score derived from one several standardized tests designed to assess human intelligence. The abbreviation “IQ” was coined by the psychologist William Stern for the German term intelligenzquotient, his terms for scoring method for intelligence tests he advocated in a 1912 book. When current IQ tests are developed, the median raw score of the norming sample is defined as IQ 100 and scores each standard deviation (SD) up or down are defined as 15 IQ points greater or less, although this was not always so historically. By this definition, approximately two-thirds of the population scores between IQ 85 and IQ 115. About 5 percent of the population scores above 125, and 5 percent below 75.
IQ scores have been shown to be associated with such factors as morbidity and mortality, parental, social status and, to a substantial degree, biological parental IQ. While the heritability of IQ has been investigated for nearly a century, there is still debate about the significance of heritability estimate and the mechanisms of inheritance.
IQ score are used for educational placement, assessment of intellectual disability, and evaluating job applicants. Even when student improve their scores on standardized tests, they don’t always improve their cognitive abilities, such as memory, attention and speed. In research contexts they have been studied as predictors of job performance, and income. They are also used to study distributions of psychometric intelligence in populations and the correlation between it and other variables. Raw scores on IQ  tests for many populations have been rising at an average rate that scales to three IQ points per decade since the early 20th century, a phenomenon called the Flynn effect. Investigation of different patterns of increase in subtest scores can also inform current research on human intelligence.

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The cognitive –psychology approach vs. psychometric approach to intelligence- American Scientist Magazine
The Limits of intelligence: The laws of physic may well prevent the human  brain from evolving into an ever more powerful thinking  machine by Douglas Fox in Scientific American, June 14, 2011.

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