‘What we are today comes from our thoughts of yesterday, and our present thoughts build our life of tomorrow: our life is the creation of our mind.’>1 The opening words of the Dhammapada, one of the most revered Buddhist scriptures, articulate an ancient and pervasive idea – the mind is all-powerful, and no element of physical reality is beyond its reach. In the West, too, the supremacy of mind over matter is championed by religious movements old and new. Christians and New Age devotees alike agree that the blind can be made to see, and invalids be made to walk, by the power of faith alone.
Science tells a rather different story. The power of the mind, it says, is strictly limited. Every effect it has on the world beyond the body must pass through the prosaic and puny conduit of muscle-power. The victim of total paralysis is completely impotent, his mind entombed, as the medical term – ‘locked-in syndrome’ – makes painfully clear. Except for the single flutter of an eyelid, which may be the only muscle to remain under voluntary control, the paralytic has no way of influencing the world around him.
But what of the world within? Even science recognises that the brain governs more than the muscles. The discovery, in the 1980s, of the rich supply of nerves linking the brain with the immune system led to the rise of a new branch of medical research known as psychoneuroimmunology (PNI). Advances in PNI have raised hopes that the powers of the mind may not be quite as impoverished as most scientists have thought. Telekinesis and extra-sensory perception may be forever alien to the scientific worldview, but perhaps scientists need not be so pessimistic when it comes to the mind’s capacity to influence events within one’s own body. Walking on water may be out of the question, but maybe – just maybe – science might discover that disease can be cured by thought alone. Will science, having exposed so many magical powers as mere fantasies, at least allow this one to stand? The heavens have been lost to Copernicus, and creation has been vanquished by Darwin. But the soul, perhaps, still lurks in the healing power of the mind.
That phrase – ‘the healing power of the mind’ – could cover a multitude of sins. Many sorts of phenomena might fall under its umbrella. Relaxation, for example, lowers blood pressure and may reduce the risk of coronary heart disease. There is nothing particularly magical about that, however. This book is about something much stranger – the possibility of a direct effect of belief on the body, an effect that is not achieved by means of any muscle, not even by the muscles that control our breathing.
Some of the apparent strangeness of the belief effect is almost certainly due to the ethereal images that are still conjured up in many people’s imaginations by the term ‘mind’. Despite the amazing scientific advances that have transformed our understanding of the brain during the past few decades, it is still common to find people speaking about the mind as if it were something completely separate from the body. While this manner of speaking is thousands of years old, it was most influentially given expression almost four centuries ago by the French philosopher René Descartes (1596–1650). Descartes argued that minds and bodies were composed of completely different kinds of substance – one spiritual in nature, the other material. Given this starting point, it is hard indeed to see how minds can affect bodies, or how bodies can affect minds. And yet they clearly do affect each other. Before I typed this sentence out on the keyboard of my computer, the words formed in my mind; when my fingers then struck the keys, their movement was yet another mundane example of the power of mind over matter. Likewise, if my mood improves after sipping a glass of wine, this is an equally familiar case of the body affecting the mind.