Theories of psychiatry do not exist an intellectual vacuum. They must mesh at many points with other bodies of knowledge. Biological psychiatry tries to prove that mental disorder and brain disorder are one and the same thing. This has no rational basis in any accepted theory of mind. This article examines two other philosophical theories that biological psychiatrists might use as their rationale: Dennett's functionalism and Searle's natural biologism. However, these avowedly antidualist theories fail, as they secretly rely on irreducibly dualist notions to complete their explanatory accounts of mind. Biological psychiatry is thus an ideology, not a scientific theory.
Keywords: theories of psychiatry; biological psychiatry; functionalism; natural biologism; dualism
Recent unsavory events in which psychiatrists are alleged to have taken large sums of money in exchange for research that produced results favorable to certain viewpoints (Citizens Commission on Human Rights International, 2009) should come as no surprise. Years ago, it was suggested that the reason psychiatry has periodic scandals is just because it has no formal model of mental disorder to define the field within which interventions may legitimately occur (McLaren, 1996). Without a declared model, there is no coherence, so that the practice of psychiatry is driven by the strongest social forces, as distinct from scientific forces. In the main, this means financial forces. Since the starting point in any scientific endeavor is a declared theory or model to limit the area of study, this renders the whole field of psychiatry prescientific. A detailed critique of the logical status of the various theories used in psychiatry (McLaren, 2007, 2009) shows that each of them fails the minimal criteria of what constitutes a scientific theory. Moreover, not one of them can be developed to the point where it could satisfy those criteria. These days, very few psychiatrists would be surprised to hear that about psychoanalysis and behaviorism, but it also applies to biological psychiatry. Despite the enormous sums of money spent on biological research in psychiatry each year, there is no accepted model of mental disorder that such research addresses. All the activity proceeds in an intellectual vacuum in which practitioners unthinkingly assume that what they are doing represents science. In fact, it is mere scientism, the inappropriate application of scientific methods and procedures to questions with no empirical content.
Because psychiatry has failed so signally to set its intellectual house in order, it is appropriate to look to other disciplines to see what they have to offer. These days, there are really only two possibilities for the title of "the correct theory of mind." The first is a reappraisal of the ancient doctrine of dualism (Chalmers, 1996), now termed "natural dualism" to distinguish it from the many forms of supernatural dualism that went before. Chalmers's case is that "consciousness must be taken seriously," specifically as an ontologically separate and causally effective factor in human behavior. Opposing this view are various forms of monism, the notion that mind and brain are not separate but are, in some crucial sense, one and the same thing. For example, the philosopher Daniel Dennett (1993) has argued powerfully against the "hopelessly contradiction-riddled myth of the distinct, separate soul" (p. 430). He espouses the monist stance known as functionalism, which takes mental states as dispositional states intervening between input and output. These states are biological in nature so that a full understanding of brain physiology will give a complete understanding of the mind.
Another philosopher, John Searle, advocates "biological naturalism." This claims that consciousness is wholly a biological phenomenon which can "no more lie around separate from my brain than the liquidity of water can be separated from the water, or the solidity of the table from the table" (Searle, 1999b, p. …