# Dualism_First published Tue Aug 19, 2003; substantive revision Fri Oct 17, 2025_This entry concerns dualism in the philosophy of mind. The term ‘dualism’ has a variety of uses in the history of ideas. In general, dualism is the view that, for some particular domain, there are two fundamental kinds. In theology, for example a ‘dualist’ is someone who believes that Good and Evil – or God and the Devil – are independent and more or less equal forces in the world. In the philosophy of mind, dualism is the theory that mind and body – or the mental and the physical – are, in some fundamental sense, different kinds of things. Dualism contrasts with monism, which says that there is only one fundamental kind; and, rather less commonly, with pluralism, which is the view that there are many fundamental kinds. Dualism usually enters philosophy as a response to the mind-body problem, where its main competitor is materialism, the form of monism that says that mind and body are both ultimately physical. Dualism is very common in the history of ideas. Today, dualism is the second most popular response to the mind-body problem among professional philosophers, after materialism and ahead of idealism and panpsychism.* * *## 1. Dualism and the Mind-Body ProblemHumans have, or seem to have, the sort of properties attributed in the physical sciences. These physical properties include size, weight, shape, colour, and motion through space and time. Humans also have, or seem to have, mental properties, which we do not attribute to typical physical objects. These mental properties include perceptual experience, emotional experience, beliefs, desires, agency, and subjecthood or selfhood. In its broadest form, the mind-body problem is the problem of explaining how humans and other mentally endowed beings end up having, or seeming to have, these very different characteristics (Weir 2023, 1–7). In a more specific form, which takes centre stage after the emergence of mechanistic science in the seventeenth century, the mind-body problem is the problem of reconciling the apparent ontological disparity between mind and body with the fact that they seem to interact closely (Westphal 2016, 1–3, 43).The problem has a number of components. These include the ontological question, what are mind and body, and is one ultimately reducible to, or in some other sense ‘nothing over and above’ the other? They also include the causal question: do physical states influence mental states, do mentals states influence physical states, and if so, how? Different aspects of the mind-body problem arise for different aspects of the mental, such as consciousness, intentionality, agency, personal identity, and subjecthood.Dualism is one of three classic responses to the mind-body problem alongside materialism and idealism (Wolff 1751). Materialism says that the mind, insofar as it truly exists, is fundamentally physical. Idealism is the converse view that matter, insofar as it truly exists, is fundamentally mental. Dualism is the view that mind and body are both real and fundamentally distinct. A fourth option which has gained prominence in recent discussions is a kind of panpsychism according to which the things described by physical science are deep-down, partly or wholly, mental in nature (Freeman 2006, Alter and Nagasawa 2015, Goff and Moran 2022). There is some disagreement as to whether these panpsychist theories form a subclass of one or more of the three classic views, or a distinctive class of their own (Weir 2023, 87–91). For an extensive taxonomy of responses to the mind-body problem as it concerns consciousness see Kuhn (2024).Dualism usually enters philosophical discussions as one possible response to the mind-body problem, especially as it pertains to consciousness. A 2020 survey suggests that dualism is, in this context, the second most popular response to the mind-body problem among professional philosophers (Bourget and Chalmers 2023). Twenty-two percent of respondents indicated that they ‘accept or lean towards’ dualism, compared to fifty-one percent for materialism and eight percent for panpsychism. Idealism was not included as a possible response to this question (though seven percent indicated that they accept or lean towards idealism in response to a question about external-world scepticism).More recently, dualism has also been discussed in the context of the ‘meta-problem of consciousness’. This is the problem of explaining why people report dualist intuitions about consciousness, or why dualism about consciousness seems true, irrespective of whether it is actually true (Chalmers 2018, Rickabaugh and Moreland 2023, 83–86). The meta-problem of consciousness arises because there is general agreement that dualism is intuitively appealing, even among its opponents (see Taliaferro 1994, 26 fn. 10). Analogous ‘meta-problems’ concerning other aspects of the mind-body problem such as intentionality and personal identity exist but have not yet received comparable attention. A final area where dualism is frequently discussed is in the philosophy of religion, where responses to the mind-body problem intersect with religious views about the soul.Other entries which concern aspects of the mind-body problem include (among many others): [behaviorism](https://plato.stanford.edu/entries/behaviorism/), [consciousness](https://plato.stanford.edu/entries/consciousness/), [eliminative materialism](https://plato.stanford.edu/entries/materialism-eliminative/), [epiphenomenalism](https://plato.stanford.edu/entries/epiphenomenalism/), [functionalism](https://plato.stanford.edu/entries/functionalism/), [identity theory](https://plato.stanford.edu/entries/mind-identity/), [intentionality](https://plato.stanford.edu/entries/intentionality/), [mental causation](https://plato.stanford.edu/entries/mental-causation/), [neutral monism](https://plato.stanford.edu/entries/neutral-monism/), [panpsychism](https://plato.stanford.edu/entries/panpsychism/), and [physicalism](https://plato.stanford.edu/entries/physicalism/).