The Genius Within by David Adam review – to what extent is intelligence determined by genes?

Zapping his brain and taking ‘smart pills’, Adam’s fascinating history of how we define intelligence raises intriguing questions about our future

The old myth that you only use 10% of your brain is obviously rubbish. If an iron spike went through the 90% you never use, why would you care? But what might be true is that we only typically use a small part of our brain’s potential function. What if you could zap your head or take a pill, like Bradley Cooper in the film Limitless, and become insanely clever? Over the last decade, this sci-fi possibility has started to approach reality, and David Adam’s book is a timely prologue to the brave new world that might await us.

On the internet you can now buy gizmos to stimulate your brain with low doses of electricity. There is some evidence that this helps with depression and other disorders, ...