I will try to make the problems posed by IQ gains go away, but do not really think that I can say the final word. I claim only that I can at last propose an interpretation that eliminates paradoxes. These paradoxes have been so intimidating as to freeze our thinking about the significance of IQ gains ever since we began to take them seriously (Flynn, 2006a).

Intelligence and the atom

Before I state the paradoxes, there are some concepts to convey. My fundamental line of argument will be that understanding intelligence is like understanding the atom: we have to know not only what holds its components together but also what splits them apart. What binds the components of intelligence together is the general intelligence factor or g; what acts as the atom smasher is the Flynn effect or massive IQ gains over time; the best IQ test to exemplify both of these is called the WISC (Wechsler Intelligence Scale for Children).

The WISC has ten subtests that measure various cognitive skills. For example, the Similarities subtest measures the ability to perceive what things have in common; the Vocabulary subtest measures whether you have accumulated a large number of the words used in everyday life; Information measures your store of general (as distinct from specialized) information; Arithmetic measures your ability to solve everyday mathematical problems (how much change you should have if you bought certain items out of a five-dollar bill); and so forth (see Box 1).