IQ is not an absolute measure of intelligence, but rather a measure relative to the rest of the human population. IQ tests are normed so that IQ scores are distributed on a normal curve with mean 100 and standard deviation 15 (Wechsler) or 16 (Stanford-Binet), as shown in the graph below. Someone with IQ of 200 is at the 99.999999987th percentile. This means that (for the Weschler test) only about 1 out of 76 billion people, would score higher. Since the world population is less than 10 billion, the concept of IQ has no meaning at or above 200. For more information, visit: What is the Highest Possible IQ for A Human? – Intelligence and IQ.
For many decades, some psychologists argued that we’re all born with approximately equal intelligence and those of high intelligence merely had richer environmental influences and worked harder than others. In 1990, Thomas J. Bouchard et al. published a seminal article titled, Sources of Human Psychological Differences: The Minnesota Study of Twins Reared Apart in which they assembled 100 sets of identical twins who were separated early in life and raised apart. All participants in the study completed about 50 hours of medical and psychological assessment. Since identical twins come from a single fertilized egg, they share virtually 100% of their alleles and can be considered to be genetically identical. Furthermore, since they were raised apart, the difference in their IQs, when tested at the end of their separation, could be entirely attributable to environmental factors. Hence, Bouchard et al. were able to estimate the difference in IQ attributable to genetics, using the correlation in the IQ scores of the twins. The researchers reported “about 70% of the variance in IQ was found to be associated with genetic variation.” The authors cautioned that this finding did not imply that IQ cannot be enhanced by rich experiences, but merely that people are born with different intellectual potential. Their environmental experiences such as education, rich experiences and hard work can help them reach that potential.
While a person of average IQ cannot increase their IQ by 30 or 40 points through hard work, it is possible to make substantial gains. A significant part of IQ is genetic and genes cannot be changed dramatically though work or practice. The good news is that recent studies in epigenetics suggest that certain genes can be “switched on” or “off” by environmental factors, so it is possible that you could increase your IQ a little during your formative years, i.e., before adulthood. A recent study suggested that some teenagers were able to change their IQ’s by as much as a standard deviation through intense work. (See: Post: Can You change your IQ? – Intelligence and IQ.)
Intense focus, combined with high interest, as well as high IQ can go a long way toward yielding results that some would perceive as “genius.” Alexander Hamilton, one of the major contributors to the creation of the US federal government founded the first US bank and the US mint, but never regarded himself as a genius, merely stating:
Men give me credit for some genius. All the genius I have lies in this; when I have a subject in hand, I study it profoundly. Day and night it is before me. My mind becomes pervaded with it. Then the effort that I have made is what people are pleased to call the fruit of genius. It is the fruit of labor and thought.
Of course, Hamilton was born with high intellectual potential and he reached it through an obsessive commitment to solving problems. Archimedes of Ancient Greece made a similar comment about his own genius in mathematics and physics.
