Twelve-year-old Nishi Uggalle, the newly crowned champion of Channel 4’s Child Genius show, is said to have an IQ “higher than Einstein’s”. It sounds impressive, and well done to Nishi for winning what is in effect a junior Mastermind programme, but does that comparison actually mean anything and how seriously should we take IQ (intelligence quotient) as a measurement of intellectual capacity?

The immediate problem is that no one knows what Einstein’s IQ was, as he was never tested. It is assumed he would have an IQ score of 160+, which is reckoned to equate with genius level. When Nishi was tested almost three years ago by Mensa, a membership organisation for people with very high IQs, she scored 162 – the highest possible score in the test she was taking, though other tests can yield higher scores and IQs of above 200 have been claimed.

The numbers are purely normative: the test-taker’s performance is scored against the average for the same age group, based on a series of tests that usually concentrate on pattern recognition, logic and problem-solving ability. The benchmark for the whole group is 100, and most people (estimates very) fall into a range between 70 and 130. Only 2.5% are reckoned to have an IQ above 130. Mensa only accepts members who are in the top 2% of those tested. Rather elitist, I suggest to a Mensa spokeswoman. “It’s easier to get into Mensa than into certain golf clubs,” she counters.

The aim of an IQ test is not to measure knowledge, but the individual’s ability to learn and their speed in absorbing information. Having zero spatial awareness, I despise them, since they expose me as a complete thicko – I once came plumb bottom in an army intelligence test to determine whether I was potential officer material. Psychologists differ wildly on whether IQ tests are reliable. Some swear by them; all we can say with certainty is that they test a particular, narrow definition of intelligence – the ability to problem-solve under pressure.

The Mensa spokeswoman claims there is a strong correlation between high IQ and good health, longevity and career success, but she also accepts a high IQ can produce social isolation. One of Mensa’s aims is to bring together “gifted” children because their general cohort may find them a little odd. I know many chess players who are brilliant problem-solvers but can barely cope with “real” life. What is intelligence? That remains the key, unanswered question.