IQ tests are available in the thousands online, but it can be difficult to know which are the most reliable.
And while it’s nice to think you can take a quick IQ test and potentially find out you’re actually a genius, people rarely wonder what that actually means – or how a set of questions can actually measure it. .
Stanford psychologist Lewis Terman once explained IQ like this:
If a subject’s “mental age” was the same as their physical age, their “intelligence quotient,” or IQ, was defined as exactly 100.
If a subject was late in mental age relative to physical age, the IQ was less than one hundred; if she was more mentally advanced, she was assigned an IQ over 100.
Unfortunately, the most comprehensive IQ test doesn’t really exist, because it doesn’t really work.
Scientists have argued that intelligence cannot simply be measured by asking a few questions and assigning a score, as much as we would like.
Siddartha Mukherjee, Pulitzer Prize-winning author of The Gene: An Intimate History, explains:
Intelligence and temperament are not marathons: there are no fixed criteria for success, no starting or finishing lines – and running sideways or backwards can ensure victory.
In short, there is no objective measure of intelligence – it’s a multi-faceted thing.