Is I.Q. a Conspiracy Theory?

Walter Lippmann vs. Lewis Terman in 1922.

One hugely popular conspiracy theory in 2025 is that I.Q. is just a hoax made up by a handful of frauds that would come tumbling down if anybody ever asked any questions about it.

It’s striking that liberals usually believe in Trust The Science, but not when it comes to the 120 year old science of psychometrics.

Many of the arguments over IQ that we see in 2025 are more than a century old. In 1922 the leading liberal pundit Walter Lippman, adviser to President Wilson, wrote six articles denouncing the young science of intelligence testing in The New Republic, of which he was one of the founders. They were largely aimed at Lewis Terman, creator of the Stanford-Binet IQ test in 1916.

Lippmann asked a lot of intelligent questions in 1922, but they’ve mostly turned out to be wrong.

The correlation between the various systems enables us to say only that the tests are not mere chance, and that they do seem to seize upon a certain kind of ability. But whether this ability is a sign of general intelligence or not, we have no means of knowing from such evidence alone. The same conclusion holds true of the fact that when the tests are repeated at intervals on the same group of people they give much the same results. Data of this sort are as yet meager, for intelligence testing has not been practiced long enough to give results over long periods of time. Yet the fact that the same child makes much the same score year after year is significant. It permits us to believe that some genuine capacity is being tested. But whether this is the capacity to pass tests or the capacity to deal with life, which we call intelligence, we do not know.

Good question.

But now we largely know.

This is the crucial question, and in the nature of things there can as yet be little evidence one way or another. The Stanford-Binet tests were set in order about the year 1914. The oldest children of the group tested at that time were 142 children ranging from fourteen to sixteen years of age. Those children are now between twenty-two and twenty-four. The returns are not in. The main question of whether the children who ranked high in the Stanford-Binet tests will rank high in real life is now unanswerable, and will remain unanswered for a generation.

Of course, four generations now have gone by.

This is just about what the intelligence test does. It does not weigh or measure intelligence by any objective standard. It simply arranges a group of people in a series from best to worst by balancing their capacity to do certain arbitrarily selected puzzles, against the capacity of all the others. The intelligence test, in other words, is fundamentally an instrument for classifying a group of people. It may also be an instrument for measuring their intelligence, but of that we cannot be at all sure unless we believe that M. Binet and Mr. Terman and a few other psychologists have guessed correctly but, as we shall see later, the proof is not yet at hand.

Well, it turned out that they did get off to a good start and further refinement over the next couple of decades made IQ tests even better at predicting important life outcomes.

Paywall here.