Online research in philosophy

Although they are often grouped together in comparison with non-dualist theories, Plato's soul-body dualism, and Descartes' mind-body dualism, are fundamentally different. The doctrines examined are those of the Phaedo and the Meditations. The main difference, from which others flow, lies in Plato's acceptance and Descartes' rejection of the assumption that the soul (= intellect) is identical with what animates the body.

To the extent that dualism is even taken to be a serious option in contemporary discussions of personal identity and the philosophy of mind, it is almost exclusively either Cartesian dualism or property dualism that is considered. The more traditional dualism defended by Aristotelians and Thomists, what I call hylemorphic dualism, has only received scattered attention. In this essay I set out the main lines of the hylemorphic dualist position, with particular reference to personal identity. First I argue that overemphasis of the problem of consciousness has had an unhealthy effect on recent debate, claiming instead that we should emphasize the concept of form. Then I bring in the concept of identity by means of the notion of substantial form. I continue by analyzing the relation between form and matter, defending the traditional theses of prime matter and of the unicity of substantial form. I then argue for the immateriality of the substantial form of the human person, viz. the soul, from an account of the human intellect. From this follows the soul's essential independence of matter. Finally, although the soul is the immaterial bearer of personal identity, that identity is still the identity of an essentially embodied being. I explain how these ideas are to be reconciled. Footnotesa I am grateful to Stephen Braude, John Cottingham, John Haldane, David Jehle, Joel Katzav, Eduardo Ortiz, and Fred Sommers for helpful comments and discussion of a draft of this essay. I would also like to thank Ellen Paul, whose suggestions have helped greatly to improve the essay's style and content.

The origin of matter is one of the last and greatest unsolved mysteries bedevilling modern attempts at understanding the philosophy of the "Enneads." There are two stages in the production of Intellect and of soul. The One or Intellect produces an undifferentiated other, which becomes Intellect or soul by itself turning towards and looking towards the prior principle, with no possibility of the One's "turning towards" or "seeing" itself. But where does matter come from? To arrive at his conception of matter, Plotinus has radically altered the definitions of non-being given by Plato and Aristotle in their refutation of Parmenides. Matter, for Plotinus, is a non-being opposed, not to "the being of each thing", as in Plato's "Sophist," but to all "the beings properly so-called", i.e. to all the forms. It is then further identified with Aristotle's definition of non-being as privation, with the crucial difference that privation, for Plotinus, is made a permanent substratum of change. This re-formulation of ideas from the "Sophist" and the "Physics" proves unmistakably that it is matter which is generated when soul produces a "non-being" which is also a "total lack of definition". The production of matter by soul does not, however, follow the model of the production of Intellect from the One or of soul from Intellect. Since matter is lifeless, it cannot turn towards its source. Soul therefore has to be herself directly responsible both for the production of matter and for the covering of matter with form. Matter is therefore included among the products which stem ultimately from the One. But the origin and the nature of matter have to be understood as very different from the double process of emanation which lies at the origin of Intellect and of soul.

The origin of matter is one of the last and greatest unsolved mysteries bedevilling modern attempts at understanding the philosophy of the "Enneads." There are two stages in the production of Intellect and of soul. The One or Intellect produces an undifferentiated other, which becomes Intellect or soul by itself turning towards and looking towards the prior principle, with no possibility of the One's "turning towards" or "seeing" itself. But where does matter come from? To arrive at his conception of matter, Plotinus has radically altered the definitions of non-being given by Plato and Aristotle in their refutation of Parmenides. Matter, for Plotinus, is a non-being opposed, not to "the being of each thing", as in Plato's "Sophist," but to all "the beings properly so-called", i.e. to all the forms. It is then further identified with Aristotle's definition of non-being as privation, with the crucial difference that privation, for Plotinus, is made a permanent substratum of change. This re-formulation of ideas from the "Sophist" and the "Physics" proves unmistakably that it is matter which is generated when soul produces a "non-being" which is also a "total lack of definition". The production of matter by soul does not, however, follow the model of the production of Intellect from the One or of soul from Intellect. Since matter is lifeless, it cannot turn towards its source. Soul therefore has to be herself directly responsible both for the production of matter and for the covering of matter with form. Matter is therefore included among the products which stem ultimately from the One. But the origin and the nature of matter have to be understood as very different from the double process of emanation which lies at the origin of Intellect and of soul.

Dr Hart sets out to answer this question by showing that the issue is as much about the nature of causation as it is about the natures of mind and matter.

Through the ages, Christians have almost automatically been Mind-Body dualists. The Bible portrays us as spiritual beings, and one obvious way to be a spiritual being is to be (or to have) an immaterial soul. Since it is also evident that we have bodies, Christians naturally have thought of themselves as composite beings, made of two substances—a material body and a nonmaterial soul. Despite the historical weight of this position, I do not think that it is required either by Scripture or by Christian doctrine as it has developed through the ages. So, I want to argue that there is a Christian alternative to Mind-Body Dualism, and that the reasons in favor of the alternative outweigh those in favor of Mind-Body Dualism.

Thomas Aquinas argues that matter is informed by a rational soul to compose a human person. But a person may survive her body’s death since a rational soul is able to exist and function without matter. This leads to the typical characterization of Aquinas as a dualist. Thomistic dualism, however, is distinct from both Platonic dualism and various accounts of substance dualism offered by philosophers such as Richard Swinburne. For both Plato and Swinburne, a person is identical to an immaterial soul that is contingently related to a human body. For Aquinas, a human person is composed of her soul and the matter it informs, but is not identical to either metaphysical component. I explicate Thomistic dualism while critically analyzing Swinburne’s account. I conclude that Aquinas’s account has theresources to address a central issue that arises for substance dualism.