Abstract: In 1987 James Flynn, a political philosopher in New Zealand, observed that intelligence test scores have been rising over the years. (This refers to the absolute score, not the standardized score.) Actually, this had been noted some years earlier, but only in Seattle, by Warner Schaie. This may be why we have a newspaper called the Intelligencer. What Flynn did was (unbeknownst to him) generalize the rise in Seattle intelligence to the rest of the developing world. These findings have been confirmed by several other observers, and in many countries. The "Flynn Effect," as it has become known, appears paradoxical because intelligence has a high genetic loading (perhaps as high as .75), yet the time period over which the Flynn effect has occurred is far too short for genetic effects to occur. (People do not breed like fruit flies.) In 1999 William Dickens and James Flynn published a mathematical model in Psychological Review, which they claimed was a "breakthrough" ! explanation, showing that the Flynn effect could only occur if there were small genetic effects.
Alas, they made some mistakes. In this presentation I will review the effect and then (a) show that their model, when fully analyzed does not require a small genetic effect, (b) that their model, as they present it, is in principle not testable barring a huge breakthrough in behavioral genetics, and (c) that some of their models can be tested by conceivable, albeit expensive, experimentation. I will close with a discussion of the role of models of this sort in scientific discourse. .