In her introduction, science writer Jo Marchant describes being offered a homeopathic remedy by another wise, sensible-seeming woman. Having learnt to bite my tongue after many similar encounters, I found her subsequent line of questioning intriguing. What causes otherwise rational people to believe in water memory? Are we all missing something?

She seeks to answer the question by researching the evidence and, in pragmatic opposition to mind–body dualism, argues that those of us of a more positivist bent underestimate the power of mind over matter. She considers all the evidence, interviewing patients and clinicians effectively.

The chapter about placebos, which includes discussion of the concept of the ‘honest placebo’, is especially good. Chronic fatigue, pain and polymyalgia are all covered well. She highlights the areas where the science provides evidence and the neuroimaging work especially supports a paradigm shift.

Some research is rather uncritically reported. Marchant states that both antidepressants (except for in major illness) and z-drugs are little better than placebos. Presented without qualification, this planted a seed of doubt in my mind about the standard of her scrutiny. However, this is not a systematic review, and generally the research she presents is backed up well.

Marchant approaches her subject with an open mind but does not venture into the realms of the incredible. Her disdain at the most obvious hokum (such as when she visits a Reiki healer) is clear. Nevertheless she presents the patients' stories with compassion. Her description of one young patient is particularly memorable; having rejected conventional treatment for breast cancer, her ‘New German Treatment’ for the resultant bone metastases involved chanting ‘I'm valuable. I love myself.’ Marchant also reminds us that other patients are desperate, having tried conventional medicine and found it not to help.

Accessible to both a lay and scientific audience, I recommend this book for anyone who has kissed a bump better, been offered arnica by a friend or asked to prescribe homeopathic remedies by a patient. Marchant reminds clinicians that we do not have all the answers and we need to help patients in the real world. Moving beyond a reductive mind v. body debate, she convinces that to be effective doctors we need to treat both.