Here are the slides I used in the talk I gave at this year’s Education Festival:

The antipathy of very many otherwise sensible people to the concept of intelligence is really quite remarkable. This aversion seems only to be increased by bringing up the subject of IQ tests. The idea that IQ tests are only useful for showing how good some people are at taking IQ tests is a deeply ignorant view based upon a breathtaking piece of intellectual dishonesty. It’s difficult to believe that people like Professor Guy Claxton who really should know better, are willing to repeat utter garbage like, Angela Duckworth’s construct ‘grit’ is a better predictor of academic success than IQ. This is entirely false. The correlation between ‘grit’ and academic acheivement is only 0.18 whereas an IQ test taken at the age of 11 produces a massive correlation (0.81) with GCSE results. (See here)

In fact, IQ scores seems to correlate positively with pretty much everything we find desirable. Whether you want children to be healthier, happier, safer, more conscientious, more creative, or to live longer, raising intelligence is probably the best route to achieving any of these ends. It even turns out that higher IQ is likely to lead to better mental health – a fact which is routinely ignored by those who believe, in the absence of any evidence that high intelligence is associated with mental illness. One of the only negative correlations that’s been found is that a higher IQ increases your likelihood of needing to wear glasses.

My argument is that increasing IQ is, relatively speaking, not that hard. Although at least 50% of intelligence is heritable, the remaining 50% or so  is a product of our environment. It’s a reasonably safe bet that the bits of intelligence that are heritable are what’s known as fluid intelligence. Crystallised intelligence – our ability to apply what we know to solve problems is most likely a product of our environment. It turns out, much to most people’s surprise, that the aspect of the environment that has the least impact on how we turn out is parenting. What seems to make the most difference is peer culture.

Schools are in a unique position to both mould peer culture and provide the raw material of crystalised intelligence: knowledge. Education has one of the strongest relationships with IQ. Not only does higher IQ lead to better educational outcomes, but more schooling leads to higher IQ. Genetic differences do not determine how children’s lives unfold, but they do have a strong effect. We make choices depending on what we’re good at and children who experience early success in school tend to have a very different academic experience. But our environment can also prevent our genetic potential being expressed. If you have a high fluid intelligence but suffer with undiagnosed glue ear during the first few years of schooling, you may not learn to read with sufficient fluency to comprehend complex texts. An education system can try to flatten the environmental landscape to ensure all children are able to develop to their full genetic potential. In a truly equitable system, all differences between children would be heritable because their experiences would be sufficiently similar so as to ensure all have equal access to a great education.

Not only can education help move the entire bell curve further to the right, individual schools and teachers can make dramatic differences to individual children’s lives.

These thoughts are the basis for a new book I’m writing. Working title: Cleverer.