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Was Descartes a Cartesian?

Descartes' Dualism

Rene Descartes, in Meditations, is the best known exponent of the theory of dualism:
        that material and mental substances are distinct entities.

From his own speculation, he developed what is now called Cartesian Dualism. This is explained separately, but the basic idea is that mental substances were not extended in space, and that material substances were composed of pure extension in space. Minds, though unextended, were thought to exist at specific places, namely, Descartes thought, in the human pineal gland.

Physicists now longer believe that substances in nature are so simply characterised as this, but Cartesian Dualism has become the most widely known formulation of dualism. Widely known, and these days, widely despised!


'Cartesianism' as a doctrine has taken on a life of its own as a position that few people want to defend, but, paradoxically, is widely believed to be held by `other people' (especially ones opponents!).

John Paley, in a recent editorial, explores some of these paradoxes in the modern acceptance and rejection of Cartesian dualism.

As does Descartes' Dualism by Baker and Morris (reviewed here by Steven Nadler).

Very often it is misrepresented. For example, very many ills of modern thought and practice are attributed to the separation of body and mind that resulted from this particular conception. Animals, for example, were not thought to have mentality, but to be like machines. Affections in the body, for another example, were not allowed to be related to mentality as such.

However, Descartes believed that 'affections in the body' were just that: in the body and not in the mind.


From the Nadler review above, we have the following comparisons of legend and a new reading:

The Cartesian Legend

  1. The "Two Worlds View": there is a private, inner world of mental objects that parallels the public, outer world of physical things. The inner world is a world of 'ideas': the outer world, a world of bodies. The mind is identified with consciousness.
  2. Anything that we would now call a 'state of consciousness' or subjective experience—concepts, beliefs, sense perceptions, bodily appetites, pains, pleasures, emotions, etc.—qualifies as a cogitatio and is placed by Descartes in the mind.
  3. The Legend misconstrues the central opposition within Descartes's dualism by setting up a contrast between consciousness and clockwork.
  4. The body is thus nothing but an unconscious, insentient machine, "a complicated bit of clockwork". Any being not endowed with a human soul—and this includes all non-human animals—therefore lacks consciousness, even sentience.
  5. There is union and interaction of the two substances in a human being. Bodily events are the real efficient causes of mental events (such as sensations) and mental events (such as volitions) are the real efficient causes of bodily motions.

What Descartes advocated, it is now argued:

  1. Descartes held that there are two (finite) substances, each with its own modifications. Thinking or having a thought is not an object or thing in a mental world, but a mode of a substance. It is, in fact, an activity or operation.
  2. The mind, they argue, is thought; it is intellectus, the rational soul. The activities of the mind, therefore, are all modalities of rational thinking: judgements, in effect, and thus propositional. Any non-cognitive event is a non-mental event. Having a sense-perception, therefore, is not to have some qualium or sense-datum hovering before the introspective soul. It just is to have a thought with a particular content, and the content describes a possible state of the body ('my eyes are being stimulated by light', for instance). To feel pain (again, in the restricted sense) is to believe or think or judge that one's body is in a certain condition.
  3. The true dichotomy is between rationality and sentience, or the moral/intellectual and the animal.
  4. Non-human animate bodies (and, in theory, even the human body without the soul) are sentient, conscious bodies. While they may not be capable of thinking (since they lack soul), they are capable of feeling and consciousness, in sum, of all those processes which do not require rationality. Brutes do not have conscientia (the self-knowledge that rational beings have of their actions) and thus they are not moral agents, but "they do share with human beings many of the things now called 'states of consciousness' "
  5. The mind-body relationship is not one of efficient causal interaction. What their mutual relationship does consist in can be called "occasionalist interaction". Motions in the brain "occasion" the soul to have (i.e., to efficiently cause or generate in itself) certain perceptions, while the mind's volitional activities are the occasion for certain bodily movements.

Other papers discussing Des Cartes and Cartesianism:

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