Science has authority not because of white coats or titles, but because of precision and transparency: you explain your theory, set out your evidence, and reference the studies that support your case.

Most bloggers have no institutional credibility, and so they must build it, by linking transparently, and allowing you to easily double check their work. But more than anything, because linking sources is such an easy thing to do, and the motivations for avoiding links are so dubious, I've detected myself using a new rule of thumb: if you don't link to primary sources, I just don't trust you.

And if, by the end [of this book], you reckon you might still disagree with me, then I offer you this: you'll still be wrong, but you'll be wrong with a lot more panache and flair than you could possibly manage right now.

Data is the fabric of the modern world: just like we walk down pavements, so we trace routes through data, and build knowledge and products out of it.

If I was writing a lifestyle book it would have the same advice on every page, and you’d know it all already. Eat lots of fruit and vegetables, and live your whole life in every way as well as you can: exercise regularly as part of your daily routine, avoid obesity, don’t drink too much, don’t smoke, and don’t get distracted from the real, basic, simple causes of ill health. But as we will see, even these things are hard to do on your own, and in reality require wholesale social and political changes.

The placebo effect is one of the most fascinating things in the whole of medicine. It's not just about taking a pill, and your performance and your pain getting better. It's about our beliefs and expectations. It's about the cultural meaning of a treatment.

Real science is all about critically appraising the evidence for somebody else's position.