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Stephen Murdoch, Duckworth Press, £20

IQ: The Brilliant Idea That Failed illuminates many of the issues surrounding the idea of intelligence testing. Stephen Murdoch writes about the impact of eugenics in the US and, in its most horrific manifestation, in Nazi Germany. This is epitomised by the story of Carrie Buck, who was sterilised with the authorisation of the US Supreme Court but without her own consent because of her "feeble mindedness".

This book deals with the wider educational and social issues of IQ testing. At a time when the Tories talk of "a grammar stream in every school" and New Labour forever hark on about exams and classifying children, the author's chapters on testing are instructive. IQ and related tests, as he shows, derive from models first produced by psychologists around the time of the First World War.

Nearly all such tests purport to measure "intelligence" objectively through devices such as verbal reasoning and tests of logic. Nearly all of them involve huge assumptions about race, class and culture. And, as every school in England can prove, it is far easier to teach children to pass tests than it is to actually help them develop intellectually.

As humans we are formed by the complex interaction of our innate capacities and our environment: we are not all the same, but all have huge potential to be so much more than how we are measured.