The ghost in the machine

While browsing recently in one of those bookshops with more scented candles than books, I came across an irresistible title on the ‘Wellness’ table: How to Make Your Brain Your Best Friend. I didn’t buy it. At my age, I’ve abandoned hope that any of my body parts might become affectionate companions. My back is aching, my knees are on strike, and as for my brain, we’re on speaking terms, but I wouldn’t call our relationship ‘best friends’.

Still, the title lingered with me. It suggests that you and your brain are two separate creatures, currently in a strained relationship, and the book promises to teach you how to win your brain over. And this way of speaking is everywhere:

• ‘My brain hates me’.

• ‘My brain won’t let me focus’.

• ‘Tell your brain it’s safe’.

• ‘Train your brain the way you train a puppy’.

• ‘I am a woman trapped in a man’s body’.

These phrases are so familiar that we forget how bizarre they are. They smuggle into everyday speech an invisible lodger, a ghostly resident somewhere behind the eyes, issuing orders, filing complaints, or begging for alternative accommodation. We talk as if there is a ‘you’ and a brain, a ghost and a machine. And the more we deny that we believe in ghosts, the more insistently they appear.

To understand why this language comes so easily, we must revisit an old debate. Classical dualism holds that the mind (or soul) is distinct from the brain or body. Plato pictured the mind as an immortal charioteer steering a mortal horse.

René Descartes sharpened the distinction into two substances: res cogitans (a thinking part that exists outside the body) and res extensa (the body).

The philosopher Gilbert Ryle coined the phrase ‘the ghost in the machine’ to mock Descartes. Ryle called dualism a category mistake: treating the mind as a non-physical thing (a ghost) lodged inside a physical body (a machine). Modern science nodded vigorously. There is no ghost, it said, only neurons. Thinking may appear to be magical, but it is just a biological process. The self does not have a separate existence; it is whatever the brain does. ‘Monism’ became the scientific default.

Unfortunately, we do not all think like scientists. For most people, Ryle’s exorcism was unsuccessful. The ghost keeps wandering back because it reflects how life feels. The weight of memory, the ache of grief, and the stubbornness of desire are not easy explained by neurophysiology. And because these experiences resist easy description, we invent dualistic linguistic shortcuts. Saying ‘my brain won’t let me sleep’ is far easier than describing the looping tangle of stress, memory, metabolism, fear, and habit that produces insomnia.

If monism were intuitive, our language would reflect it. Instead, dualism leaks in everywhere. Even scientists talk like dualists. Neuroscientists warn that ‘your brain wants to keep you safe’, as though the brain were a helicopter parent. Psychologists urge you to ‘teach your brain new habits’, as if the brain were an underperforming student. Cognitive scientists talk about ‘the self-model’, inadvertently conjuring up a tiny administrator living in your head updating internal spreadsheets. This is not science; it is simply dualism dressed in a lab coat.

The most consequential modern dualism appears not in philosophy seminars but in operating theatres. In gender medicine, the inner self, the ghost, is treated as the ‘real’ person. The body is simply a correctable error.

This is not an argument against caring. People who suffer from gender dysphoria deserve help and compassion, not slogans. The problem is the metaphysical muddle that too often leaves them without good options. When we treat the body as a mistake and the inner ghost as infallible, we are staging a philosophical and theological conflict while pretending it is merely clinical medicine.

It seems that, for all our modern certainty, the ancient idea of the soul simply refuses to disappear. We keep smuggling it back under gentler names—identity, consciousness, agency, personhood, ‘the real me’. By ‘soul’, I do not mean a stowaway hiding in the skull, but the depth and coherence of a person, the interior life that no MRI or algorithm can meaningfully represent.