Mind, Body and Soul: What the Great Philosophers Have Said About What You Really Are (Part 1)

You walk into the edge of the bed. Pain shoots up your foot. A neuroscientist could, in principle, describe everything happening in your body at that moment: the nerves firing, the signals travelling to your brain, the regions lighting up.

But something seems missing from that description. It does not say what the pain feels like. You know that part better than anyone, and yet it appears nowhere in the science.

That small gap is the doorway into one of the oldest questions people have asked. What is the relationship between your mind, your body and whatever people mean by the soul? You do not need any background to follow the answers. You already have the most important piece of evidence: your own experience.

The Greek philosopher Plato, writing around 2,400 years ago, gave one of the most influential answers. In his dialogue the Phaedo, he argued that the soul is separate from the body and survives death. He thought the soul belonged with eternal, unchanging truths, while the body belonged to the changing physical world.

His student Aristotle took a different path. In his work On the Soul, he defined the soul as what makes a living body alive. For Aristotle, soul and body are not two things stuck together. The soul is the body’s form: its organisation and its way of working.

One everyday way to picture this is a knife. Its ability to cut is not a separate object hidden inside it. It is just what the knife is and does. On Aristotle’s view, plants have a soul that allows growth and nourishment, animals add perception, and humans add the power of reason.

The 13th-century Christian thinker Thomas Aquinas combined Aristotle’s ideas with Christian belief. He agreed that the soul is the form of the body. But he argued that the human intellect, our power to think, works independently of the body, and so the soul can survive death. He also held that a human being is the whole person, body and soul together, not the soul alone.

Buddhist philosophy offers a strikingly different answer. The doctrine of no-self, called anatman in Sanskrit, holds that there is no permanent self or soul at all. What we call a person is a changing bundle of five elements: the body, feelings, perceptions, mental habits and intentions, and consciousness.

A famous Buddhist text, the Questions of King Milinda, compares a person to a chariot. There is no chariot apart from the wheels, axle and frame. ‘Chariot’ is just a useful name for the parts working together. In the same way, ‘self’ is a name for a stream of connected experiences, not a hidden thing behind them.

Religious believers today hold a wide range of views, and many see no conflict between faith and a scientific picture of the brain. This guide sets out the main philosophical positions rather than judging any faith.

The French philosopher René Descartes gave dualism its most famous modern form in his Meditations of 1641. He noticed that he could doubt that his body existed, but he could not doubt that he was thinking. From this he concluded that the mind is a thinking thing, completely different from the body, which takes up space.

The sharpest challenge came quickly, from Princess Elisabeth of Bohemia in her letters to Descartes. If the mind is not physical and takes up no space, how can it move your arm? And how can a knock to the head affect your thoughts? This became known as the interaction problem, and it has never gone away.

In 1949, the Oxford philosopher Gilbert Ryle mocked Descartes’ picture as ‘the ghost in the machine’. In The Concept of Mind, he argued that treating the mind as a separate object was a basic confusion, like a visitor who is shown the colleges, libraries and laboratories of a university and then asks, ‘But where is the university?’

Today, physicalism is the most common view among professional philosophers, as the survey below shows. It says the mind is not something extra. Thoughts, feelings and memories are the activity of the brain and body. Supporters point to how closely the mind depends on the brain: drugs, sleep, injury and illness that affect the brain also change how we think and feel.

One popular version is functionalism. It says a mental state is defined by the job it does. Pain is whatever is caused by damage, makes you want to avoid it and makes you say ‘ouch’. On this view, the mind is a little like software running on the brain’s hardware. The same software could, in principle, run on something else, such as a computer or an alien made of silicon.

Physicalism explains a great deal. But three famous thought experiments suggest something might be left out.

In 1995, the philosopher David Chalmers gave this puzzle a name. The ‘easy problems’, he said, are explaining how the brain processes information, controls behaviour and stores memories. They are hard in practice but science knows how to approach them. The ‘hard problem’ is explaining why all that processing is accompanied by experience at all.

Physicalists have strong replies. Some argue Mary learns no new fact, only a new ability, such as being able to recognise and imagine red. Others argue she learns an old fact in a new way. Interestingly, Frank Jackson himself later changed his mind and came to accept physicalism.

Panpsychism: consciousness all the way down

Panpsychism sounds strange at first. It says that consciousness, in some extremely simple form, is a basic feature of matter, like mass or electric charge. Your rich inner life is built from countless tiny flickers of experience.

Philosopher Philip Goff defends this in his 2019 book Galileo’s Error. He argues that physics tells us what matter does, but not what it is in itself, and that consciousness may fill that gap. Its biggest challenge is the combination problem: how do billions of tiny experiences combine into one unified mind like yours?

Illusionism: consciousness is not what it seems

At the opposite end, the American philosopher Daniel Dennett argued that there is no deep mystery left once all the brain’s functions are explained. Illusionists say that our sense of having private, indescribable inner qualities is itself something the brain produces. Experiences are real, they argue, but they are not the magical inner glow they seem to be.

The neuroscientist’s view

Neuroscientist Anil Seth of the University of Sussex takes a practical route in his 2021 book Being You. Rather than solving the hard problem head on, he focuses on what he calls the ‘real problem’: explaining why particular patterns of brain activity go with particular experiences. He describes perception as a ‘controlled hallucination’, in which the brain constantly predicts the world and checks those guesses against the senses.

This question has moved from science fiction to everyday life. If functionalism is right, a machine running the right program could, in principle, think and perhaps feel.

In 1980, the philosopher John Searle challenged this with the Chinese Room. Imagine you sit in a room with a rulebook. Notes in Chinese are passed in. By following the rules, you pass back perfect replies in Chinese. To people outside, the room understands Chinese. But you do not understand a word. Searle concluded that following rules for symbols is not the same as understanding them.

Critics reply that while the person in the room does not understand Chinese, the whole system of person, rulebook and room might. Others argue a machine connected to the world through cameras and movement could come to understand. The debate is very much alive as AI chatbots become more fluent.

Your body has grown and changed since you were a child, and so have your beliefs. So what makes you the same person?

The 17th-century English philosopher John Locke argued that personal identity rests on psychological connections, especially memory. A rival view, called animalism, says you are simply a human animal, and you continue as long as that living body does.

The Oxford philosopher Derek Parfit pushed the question further in his 1984 book Reasons and Persons. He imagined a teleporter that scans you, destroys your body and builds an exact copy on Mars. Is the person on Mars you? Parfit concluded that what really matters is not identity itself, but the continuation of your memories, character and plans. Some readers find this unsettling. Others find it oddly freeing.

The PhilPapers Survey, run by philosophers David Bourget and David Chalmers, asked professional philosophers, mostly in North America, Europe and Australasia, for their views in 2020. Respondents could accept or lean towards a position.

Two things stand out. Physicalism is the most popular view, but it is far from unanimous. And a clear majority of philosophers, including many physicalists, agree that consciousness poses a genuinely hard problem.

This is a question where the evidence does not settle the matter, and thoughtful people disagree. Here are the strongest versions of the two broad camps.

Between these camps sit many middle positions. The honest summary is that the question remains open, and the best minds who have studied it most closely still disagree.

You will not settle the mind-body problem this week. Nobody has in 2,400 years. But you can enjoy the question. The next time you feel the warmth of the sun or the sting of a stubbed toe, you are standing right at the edge of one of the deepest puzzles there is. That is not a bad place to stand.

This content is for general information only and does not constitute legal, financial, medical or professional advice. It describes philosophical positions for educational purposes and does not endorse or reject any religious or personal belief.