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Genius: An Overview
by William E. Benet, Ph.D., Psy.D.
January, 2005

Genius is one of the oldest and yet one of the most elusive concepts in the history of psychology, and also one of the most fascinating.  Originally, in Graeco-Roman antiquity, genius referred to a quality that everyone possessed, an animating spirit that represented one's character and interests as much as one's ability. Over time,  however, it became increasingly associated with one's natural ability or talent, and eventually with the special ability of a few.  Nineteenth century British psychologist Francis Galton, citing British author and lexicographer Dr. Samuel Johnson as a paragon example,  described genius as "a man endowed with superior faculties."  And then, in  the early part of the 20th century, as interest in psychometric methods of assessment grew, genius became associated with a quantitative concept known as the Intelligence Quotient or IQ, which further adulterated its original meaning.  Expressed as a ratio score, IQ was was the ratio of  an individual's estimated mental age and chronological age multiplied by 100. In 1916,  Stanford University psychologist Lewis M. Terman, Ph.D., classified an IQ score of 140 or higher as "genius or near genius", a classification that is no longer used.  Ironically, one of the first practical applications of IQ tests was to identify children who were mentally handicapped, not gifted.  Alfred Binet, the French psychologist who developed The Binet-Simon Intelligence Scale in 1905, which Terman would later revise and use to identify gifted children, was dismayed by this subsequent application of his test. Today, not only have high IQ scores become used to identify children for gifted programs, but in popular parlance have become equated with genius. This is very unfortunate since, as we shall see, the relationship between high IQ scores and genius is not always apparent. In fact, history is full of geniuses who more than likely had ordinary IQs.

For qualitative descriptions of various IQ ranges used by psychologists today, see IQ Classifications at

In 1926, Stanford University psychologist Catharine Morris Cox, Ph.D., published a pioneering study, The Early Mental Traits of 300 Geniuses,  which fueled popular interest in the association between genius and IQ. In her study, 301 eminent persons (not 300 as suggested by the title) born between 1450 and 1850 were assigned estimated IQ scores based on ratings of individual case histories of their behavior and performance in childhood and young adulthood, prepared from 1,500 biographical sources. Their IQ scores were reported as ratio quotients using The Stanford Revision and Extension of the Binet-Simon Intelligence Scale as a reference point. Today, Stanford-Binet IQ scores are expressed as deviation quotients based on a normally distributed population with a mean of 100 and a standard deviation of 16. For a normally distributed (bell-shaped) population, a mean of 100 is the point at which a score is equal to or greater than the scores of 50 percent of the population. An average score is generally considered to be any score that falls within one standard deviation above or below the mean (100 +/- 16 or 84-116 on the Stanford-Binet scale and 85-115 on the Wechsler intelligence scales, which have a standard deviation of 15, and are the most commonly used IQ tests today).

The study reported estimates for both age groups and estimates that were corrected for regression to the mean. Cox observed that the more reliable the case history data (for which reliability grades were assigned and coefficients computed), the higher the estimated IQ, and concluded that the lowest IQs may have been spuriously underestimated. To correct for this regression to the mean, she used a a statistical method that adds to the obtained score an increment which it would have received had the estimate been made using the mean of  the averages of the obtained IQ estimates of both childhood and young adulthood case history ratings.

Cox believed that even her corrected scores were too low, but in comparison to the highest scores that today's standard IQ tests are able to measure, they seem spuriously inflated. Not surprisingly, it is these extremely high scores in Cox's study that seem to most fascinate the public, such as the 17 "Great Minds" from Cox's study highlighted in Time's Life Science Library edition, The Mind (1964), lead by Goethe with an IQ of 210.

The highest score that can be obtained on the Wechsler Intelligence Scale for Children-III, which is the preeminent test of intelligence used in the United States today for identifying gifted children, is 160. For the Wechsler Adult Intelligence Scale-III, the ceiling is slightly lower: 155. There are other tests, such as the Stanford-Binet that can yield higher scores, but to what end? Cox wrote that her scores were never intended to be exact measures, but were more useful as indicators for comparing the relative eminence of her 301 geniuses. Yet, even this is questionable. The word "genius" is derived  from the Latin verb "gignere", which means to beget or produce. Historically, genius referred to one's ability to accomplish or create something, something that performance on an IQ test does not measure.  Consider Einstein, for example: as a child, he was delayed in speech and was a poor student who dropped out of school at one point and failed to pass the entrance examination for admission to the Swiss Federal Institute of Technology in Zurich. He was eventually admitted after retaking the examination two years latter, and graduated, but was unable to obtain a university teaching position, and went to work instead as an assistant technical clerk in the patent office in Bern, Germany.  Einstein was well on his way to what appeared to be an entirely uneventful and undistinguished career.  Using the same method that Cox did to rate geniuses based on their behavior and performance either in childhood or young adulthood up to the age of 26, Einstein would have received one of the lowest IQ scores on her list of geniuses.

Einstein's IQ is unknown. It has never been tested, but there is no question that he was one of the greatest geniuses of the 20th century. There have been other geniuses who, if they had been tested,  may not have obtained very high scores, or even above average scores, on an IQ test, especially in the arts and literature. It is interesting but idle to speculate how, say,  Picasso or Hemingway or any number of artists or writers might have scored. And then there are geniuses in other fields of endeavor, such as sports and entertainment, for whom a discussion of IQ seems completely irrelevant.

Harvard University psychologist Howard Gardner, Ph.D., has identified ten different types of Intelligence. Only two or three types (logical-mathematical, linguistic and spatial intelligence) are commonly represented in contemporary IQ tests. The other seven (musical, bodily-kinesthetic, interpersonal, intrapersonal, naturalist, spiritual and existential intelligence ) are generally excluded. Yet, individuals who are gifted in these other areas can have an impact on society that inspires, uplifts, transforms, or simply entertains, which is no less important than the highest achievements in the areas of ability that are measured by most IQ tests. Think of how many people of both high and low intellectual ability have found inspiration or refuge, as well as simple enjoyment, in the music of, say, Ray Charles or Hank Williams, who have had an impact on generations of listeners that is no less profound than the composers of other genres. Genius, as Gardner suggests, can manifest itself in other ways besides a high IQ score.  And a high IQ score is by no means a guarantor of success and accomplishment in life. Consider William James Sidis, who reportedly had the highest IQ in history.

The story of Sidis, whose IQ was estimated to be over 250, was, by every account, phenomenally gifted.  Grady M. Towers, in an article in Gift of Fire (the journal of the Prometheus Society), wrote that at eighteen months Sidis could read The New York Times, at two he taught himself Latin, and at three he learned Greek. By the time he was an adult, he could speak more than forty languages and dialects. He graduated  from Harvard cum laude at sixteen, and became the youngest professor in history at Rice University.  Towers wrote, "Of all the prodigies for which there are records, his was probably the most powerful intellect of all. And yet it all came to nothing. He soon gave up his position as a professor, and for the rest of his life wandered from one menial job to another."

In a longitudinal study of 250,000 gifted California children beginning in the 1920's,  Terman (under whom Cox studied)  found that in 1940 when the group was around 29 years of age, for those who had IQ scores of approximately 140 or higher, there was a moderate inverse relationship between performance on the Concept Mastery Test, Form A, a test of verbal intelligence, and personal adjustment.  In another study by Columbia Teacher's College psychologist Leta S. Hollingworth, Ph.D., Children Above 180 IQ (1942), she concluded that there was an IQ range of optimum productivity and personal adjustment between 125 and 155.  Scores in this range are typical of the scores obtained by U.S. school children who are referred by their teachers for gifted education programs. The cutoff for eligibility in some states is an IQ score that is among the top two percent of the population, which is a score of 130 on the Wechsler scales (or 132 on the Stanford-Binet scale).  But it is not always the sole criterion. Just as importantly, superior academic achievement and interests that foster achievement are often considered in making a final determination for gifted program placement. While this process is commendable for recognizing that IQ is only one facet of giftedness, it is not without controversy for failing to recognize the many gifted, ambitious, and motivated children scoring below the cutoff who would also benefit from an enriched curriculum and the emotional trauma for those children who are not accepted.

I am often asked by children, whom I evaluate for gifted programs, and their parents, what is a "genius IQ score?" And I tell them, quite matter of factly, there is none. Genius is what one accomplishes in life, not the score one makes on a test of mental ability. As a practical guideline, I advise parents, who are typically more concerned than their children about what their scores mean, that any child that scores around 115 (or higher than two thirds of their peers) has the general intellectual ability to succeed in virtually any endeavor that is accompanied by interest and application.  University of California at Berkley educational psychologist Arthur Jensen, Ph.D., wrote that beyond one standard deviation above the mean (an IQ score of around 115), "the IQ level becomes relatively unimportant in terms of ordinary occupational aspirations and criteria of success."

For those who score higher than this, the only limitations are drive and desire plus the ability to initiate and carry out tasks or simply the ability to get things done.  Drive and desire cannot be overstressed. There are many stories of geniuses with extremely high IQs who also had a burning desire to achieve. American chess genius and former world champion, Bobby Fischer, "lived and breathed chess."  No one worked harder at mastering the game than Fischer, even though his reported IQ of 187, was among the highest in history; but, unfortunately, like Sidis, Fischer represented one of the sadder chapters in the annals of American geniuses. Plagued by inner demons,  Fischer completely withdrew from competition after winning the world championship in 1972 at the age of 28 and has accomplished nothing significant since then.  On the other end of the IQ spectrum was one of America's greatest inventive geniuses: Thomas Alva Edison. Like Einstein, he was not a very good student, and quite likely would not have scored very high on an IQ test in childhood. But Edison, like all geniuses of great accomplishment, had boundless drive, and  understood perfectly the essence of genius when he wrote, "Genius is one percent inspiration and 98 percent perspiration."

What then are some of the more meaningful uses IQ scores? IQ testing is one of the most precise psychometric methods used by psychologists for assessing individual differences in general intellectual ability and is extremely useful for assessing academic aptitude. In clinical settings, cognitive testing is indispensable in assessing a wide range of neuropsychological deficits resulting from such disorders as stroke, Alzheimer's disease, and closed head trauma.  These deficits may be sudden or gradual and progressive, and cannot be as precisely measured by other means, such as CT or MRI scans or lab tests as well as psychometric means.  IQ testing is extremely useful in accurately assessing and identifying children who are mentally handicapped as well as gifted. They are also useful in occupational screening and have been used by the U.S. Armed Forces since WWI for screening and classifying recruits for job assignments. See

Where IQ tests are less useful is in making meaningful distinctions between different IQ levels at the extremes of ability, both above and below the mean, but especially the former. This is due in part to the decreasing discrimination between subtest scale scores at the extremes of performance. For example, on the Vocabulary subtest of the Wechsler Intelligence Scale for Children-III, (this subtest correlates more strongly with overall intellectual ability than the other 12 subtests), the raw score difference between a scale score of 10 and 13, which represents a one standard deviation difference, is 7-10 points for a 16-year old; while the difference between a scale score of 16 and 19, which is also a one standard deviation difference, but two to three standard deviations above the mean, is only three points.  Correct responses on the Vocabulary subtest are scored as either one or two points, depending on the quality of the response. Using Wechsler's system of classification, the difference between Average and High Average intelligence on this subtest may reflect a difference of as much as  5-10 correct responses; while the difference between Superior and Very Superior intelligence may reflect a difference of only two correct responses. The latter is hardly a substantial difference, and at the higher levels of IQ, not a particularly meaningful one.

We can conclude, by once again quoting Jensen, who wrote, "That is not to say that there are not real differences between the intellectual capabilities represented by IQs of 115 and 150 or even between IQs of 150 and 180. But IQ differences in this upper part of the scale have far less personal implications than the thresholds just described and are generally of lesser importance for success in the popular sense than are certain traits of personality and character." (italics added--WEB).

William E. Benet, Ph.D., Psy.D.

Selected References

  • Cox, C. M. (1926) The early mental traits of three hundred geniuses. In Terman, L. M. (Ed.). Genetic Studies of Genius (Vol. II). Stanford University Press.

  • Galton, F. (1869). Hereditary Genius: An Inquiry into its Laws and Consequences. London: Macmillan/Fontana.

  • Gardner, H. (1998). Are there additional intelligences? The case for naturalist, spiritual, and existential intelligences. In J. Kane (Ed.), Education, Information, and Transformation (pp. 111-131). Upper Saddle River, NJ: Merrill-Prentice Hall.

  • Gardner, H. (1983). Frames of Mind: The Theory of Multiple Intelligences. New York: Basic Books.

  • Hollingworth, L. S. (1942). Children Above 180 IQ: Stanford-Binet Origin and Development. Yonkers, NY: World Book.

  • Jensen, A. (1980). Bias in Mental Testing. New York: Free Press.

  • Terman, L. M. (1916). The Measurement of Intelligence. Boston: Houghton Mifflin.

  • Terman, L. M. & Oden, M. H. (1947). The gifted child grows up: twenty-five years' follow-up of a superior group. In Terman, L. M. (Ed.). Genetic Studies of Genius (Vol. IV). Stanford University Press.

  • Towers, G. M. (1987). The outsiders. Gift of Fire (Journal of the Prometheus Society),  Issue No. 22.

  • Wechsler, D. (1997). Wechsler Adult Intelligence Scale-Third Edition. San Antonio: The Psychological Corporation.

  • Wechsler, D. (1991). Wechsler Intelligence Scale for Children-Third Edition. San Antonio:   The Psychological Corporation.

  • Wilson, J. (1964). The Mind. New York: Time.

Copyright © 2005 W. E. Benet, Ph.D., Psy.D. All Rights Reserved.

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