For it is quite certain that we can never adequately come to know the organized beings [living things] and their internal possibility in accordance with merely mechanical principles of nature, let alone explain them; and indeed this is so certain that we can boldly say that it would be absurd for humans even to make such an attempt or to hope that there may yet arise a Newton who could make comprehensible even the generation of a blade of grass according to natural laws that no intention has ordered; rather, we must absolutely deny this insight to human beings.
What did Kant mean by this and what is its application to psychiatry? As a critical psychiatrist I think I am applying Kant’s critical philosophy to psychiatry.
What Kant was saying is that a mechanistic psychology is impossible. Not that people cannot be studied in a mechanical way, particularly parts of themselves - and as far as psychology is concerned this is the brain - nor that we cannot produce descriptions of thoughts, emotions and behaviour. But a mechanistic conception of nature fails to provide a complete characterisation of living systems.
Why is this? Living things are different from inanimate objects. They have functional and goal-directed characteristics. They have designed and designer-like aspects. They seem to be intended for a definite purpose and they have the ability to form their parts. Living things are purposiveness systems, or to use Kant’s words, teleological systems. A machine is different. It does not serve its own interests but the interests of its maker or user. Organisms, unlike machines, are self-organising and self-reproducing systems.
We therefore need different modes of explanation for teleological and mechanical points of views. For example, understanding the meaning of human action is a different kind of explanation from mechanical explanation. The mechanistic conception of causality fails to provide a complete understanding of human and living systems in general.
In fact, Kant goes further than this. What he says is that how living wholes cause their parts is unknowable to us. We just have to accept that our knowledge is limited because we conceptualise organic matter in a different way to inorganic matter. Life and human sciences are doomed to a kind of pre-scientific descriptivism rather than becoming a natural science.
We can never have theoretical knowledge that anything in nature is teleological, but such judgment is nonetheless necessary and beneficial for us. Which is why we attempt to understand human and living behaviour in mechanical terms. We may well wish we could explain life in mechanistic scientific terms and so-called science has often embarked on what Kant called a “daring adventure of reason”. Despite Kant recognising the wish to have a physical understanding of life and human behaviour, nonetheless he argued that it is absurd and futile to expect to be able to explain mental processes in physical terms.
I want to try and apply this kind of thinking to psychiatry. Mental illness is commonly perceived to be due to brain pathology. This is standard understanding. People may even be told by doctors that their mental health problems are due to a chemical imbalance in the brain or some other biological disease. You may even have heard or read something like this yourself. But critical psychiatry is saying you are being misled by perspectives like this.
Of course acute brain disorders can present as a toxic confusional state. More chronically they can lead to a dementia. But most mental health problems are functional in the sense that they are not structurally represented in the brain.
I don’t want to be misunderstood. Of course I’m not saying that mental health problems have nothing to do with the brain. The mind is clearly enabled by the brain. But what I’m saying is that mental health problems should not be reduced to the brain. And, like Kant, this is primarily a statement about how one explains mental health problems. I’m not saying that mind and brain are different substances. I’m not anti-materialist in this sense. Nor am I saying that it’s not important to use scientific methods. In fact, a lot of what passes for science, certainly in mental health, is more to do with speculation than the real world. Considering the amount of money that’s been spent on mental health research, one might hope that progress would have been made. But essentially results are so clouded by inconsistencies and confounders that it’s not been possible to say anything definitive about the biological basis of mental illness.
You may be surprised by me taking such a position as this. And, you may well not be alone. I am taking a minority view within psychiatry. In fact, psychiatry is more like a faith that doctors are expected to believe in rather than a science as such. If I don’t follow the faith of believing that mental illness is a brain disease, then I’m seen as unorthodox. I do, however, have a few other psychiatrists who agree with me. Twenty years ago we formed the Critical Psychiatry Network. If you’re interested in finding out more, there’s an editorial in February's British Journal of Psychiatry entitled ‘Twenty years of the Critical Psychiatry Network’.
(Adaptation of talk given to Cambridge University Psychology Society, 21 February 2019)