Property dualism describes a category of positions in the
philosophy of mind
Philosophy of mind is a branch of philosophy that studies the ontology and nature of the mind and its relationship with the body. The mind–body problem is a paradigmatic issue in philosophy of mind, although a number of other issues are addre ...
which hold that, although the world is composed of just one kind of
substance—
the physical kind—there exist two distinct kinds of properties:
physical properties and
mental properties. In other words, it is the view that non-physical, mental properties (such as thoughts, imagination and memories) exist in, or naturally
supervene
In philosophy, supervenience refers to a relation between sets of properties or sets of facts. X is said to supervene on Y if and only if some difference in Y is necessary for any difference in X to be possible. Some examples include:
* Whether t ...
upon, certain physical substances (namely
brains
A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a v ...
).
Substance dualism, on the other hand, is the view that there exist in the universe two fundamentally different kinds of substance: physical (
matter
In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic partic ...
) and non-physical (
mind
The mind is the set of faculties responsible for all mental phenomena. Often the term is also identified with the phenomena themselves. These faculties include thought, imagination, memory, will, and sensation. They are responsible for various m ...
or
consciousness
Consciousness, at its simplest, is sentience and awareness of internal and external existence. However, the lack of definitions has led to millennia of analyses, explanations and debates by philosophers, theologians, linguisticians, and scien ...
), and subsequently also two kinds of properties which inhere in those respective substances. Substance dualism is thus more susceptible to the
mind–body problem
The mind–body problem is a philosophical debate concerning the relationship between thought and consciousness in the human mind, and the brain as part of the physical body. The debate goes beyond addressing the mere question of how mind and bo ...
. Both substance and property dualism are opposed to
reductive physicalism
In philosophy, physicalism is the metaphysical thesis that "everything is physical", that there is "nothing over and above" the physical, or that everything supervenes on the physical. Physicalism is a form of ontological monism—a "one substa ...
.
Non-reductive physicalism
Non-reductive physicalism is the predominant contemporary form of property dualism according to which mental properties are mapped to
neurobiological
Neuroscience is the scientific study of the nervous system (the brain, spinal cord, and peripheral nervous system), its functions and disorders. It is a multidisciplinary science that combines physiology, anatomy, molecular biology, developme ...
properties, but are not
reducible to them. Non-reductive physicalism asserts that mind is not ontologically reducible to matter, in that an ontological distinction lies in the differences between the properties of mind and matter. It asserts that while mental states are physical in that they are caused by physical states, they are not ontologically reducible to physical states. No mental state is the same one thing as some physical state, nor is any mental state composed merely from physical states and phenomena.
Emergent materialism
Emergentism is the idea that increasingly complex structures in the world give rise to the "emergence" of novel properties that are something over and above (i.e. cannot be reduced to) their more basic constituents (see ''
Supervenience
In philosophy, supervenience refers to a relation between sets of properties or sets of facts. X is said to supervene on Y if and only if some difference in Y is necessary for any difference in X to be possible. Some examples include:
* Whether t ...
''). The concept of
emergence
In philosophy, systems theory, science, and art, emergence occurs when an entity is observed to have properties its parts do not have on their own, properties or behaviors that emerge only when the parts interact in a wider whole.
Emergence ...
dates back to the late 19th century.
John Stuart Mill
John Stuart Mill (20 May 1806 – 7 May 1873) was an English philosopher, political economist, Member of Parliament (MP) and civil servant. One of the most influential thinkers in the history of classical liberalism, he contributed widely to ...
notably argued for an emergentist conception of science in his 1843 work ''
A System of Logic
''A System of Logic, Ratiocinative and Inductive'' is an 1843 book by English philosopher John Stuart Mill.
Overview
In this work, he formulated the five principles of inductive reasoning that are known as Mill's Methods. This work is important ...
''.
Applied to the mind/body relation,
emergent materialism
In the philosophy of mind, emergent (or emergentist) materialism is a theory which asserts that the mind is irreducibly existent in some sense. However, the mind does not exist in the sense of being an ontological simple. Further, the study of m ...
is another way of describing the non-reductive physicalist conception of the mind that asserts that when matter is organized in the appropriate way (i.e., organized in the way that living human bodies are organized),
mental properties emerge.
Anomalous monism
Many contemporary non-reductive physicalists subscribe to a position called
anomalous monism (or something very similar to it). Unlike epiphenomenalism, which renders mental properties causally redundant, anomalous monists believe that mental properties make a causal difference to the world. The position was originally put forward by
Donald Davidson in his 1970 paper ''Mental Events'', which stakes an identity claim between mental and physical tokens based on the notion of supervenience.
Biological naturalism
Another argument for non-reductive physicalism has been expressed by
John Searle
John Rogers Searle (; born July 31, 1932) is an American philosopher widely noted for contributions to the philosophy of language, philosophy of mind, and social philosophy. He began teaching at UC Berkeley in 1959, and was Willis S. and Mario ...
, who is the advocate of a distinctive form of physicalism he calls biological naturalism. His view is that although mental states are not
ontologically
In metaphysics, ontology is the philosophical study of being, as well as related concepts such as existence, becoming, and reality.
Ontology addresses questions like how entities are grouped into categories and which of these entities exis ...
reducible to physical states, they are causally reducible (see
causality
Causality (also referred to as causation, or cause and effect) is influence by which one event, process, state, or object (''a'' ''cause'') contributes to the production of another event, process, state, or object (an ''effect'') where the cau ...
). He believes the mental will ultimately be explained through neuroscience. This worldview does not necessarily fall under ''property dualism'', and therefore does not necessarily make him a "property dualist". He has acknowledged that "to many people" his views and those of property dualists look a lot alike. But he thinks the comparison is misleading.
Epiphenomenalism
Epiphenomenalism
Epiphenomenalism is a position on the mind–body problem which holds that physical and biochemical events within the human body ( sense organs, neural impulses, and muscle contractions, for example) are the sole cause of mental events (thought, ...
is a doctrine about mental-physical causal relations which holds that one or more mental states and their properties are the by-products (or
epiphenomena
An epiphenomenon (plural: epiphenomena) is a secondary phenomenon that occurs alongside or in parallel to a primary phenomenon. The word has two senses: one that connotes known causation and one that connotes absence of causation or reservation ...
) of the states of a closed physical system, and are not causally reducible to physical states (do not have any influence on physical states). According to this view mental properties are as such real constituents of the world, but they are causally impotent; while physical causes give rise to mental properties like
sensation
Sensation (psychology) refers to the processing of the senses by the sensory system.
Sensation or sensations may also refer to:
In arts and entertainment In literature
* Sensation (fiction), a fiction writing mode
* Sensation novel, a Britis ...
s,
volition,
idea
In common usage and in philosophy, ideas are the results of thought. Also in philosophy, ideas can also be mental representational images of some object. Many philosophers have considered ideas to be a fundamental ontological category of being ...
s, etc., such mental phenomena themselves cause nothing further - they are causal dead ends.
The position is credited to English biologist
Thomas Huxley
Thomas Henry Huxley (4 May 1825 – 29 June 1895) was an English biologist and anthropologist specialising in comparative anatomy. He has become known as "Darwin's Bulldog" for his advocacy of Charles Darwin's theory of evolution.
The stor ...
(Huxley 1874), who analogised mental properties to the whistle on a steam locomotive. The position found favour amongst scientific
behaviourists over the next few decades, until
behaviourism
Behaviorism is a systematic approach to understanding the behavior of humans and animals. It assumes that behavior is either a reflex evoked by the pairing of certain antecedent stimuli in the environment, or a consequence of that individual ...
itself fell to the
cognitive revolution
The cognitive revolution was an intellectual movement that began in the 1950s as an interdisciplinary study of the mind and its processes. It later became known collectively as cognitive science. The relevant areas of interchange were between th ...
in the 1960s. Recently, epiphenomenalism has gained popularity with those struggling to reconcile non-reductive physicalism and
mental causation.
Epiphenomenal qualia
In the paper "Epiphenomenal Qualia" and later "What Mary Didn't Know"
Frank Jackson made the so-called knowledge argument against physicalism. The
thought experiment
A thought experiment is a hypothetical situation in which a hypothesis, theory, or principle is laid out for the purpose of thinking through its consequences.
History
The ancient Greek ''deiknymi'' (), or thought experiment, "was the most anc ...
was originally proposed by Jackson as follows:
Jackson continued:
Panpsychist property dualism
Panpsychism is the view that all matter has a mental aspect, or, alternatively, all objects have a unified center of experience or point of view. Superficially, it seems to be a form of property dualism, since
it regards everything as having both mental and physical properties. However, some panpsychists say that mechanical behaviour is derived from the primitive mentality of atoms and molecules — as are sophisticated mentality and organic behaviour, the difference being attributed to the presence or absence of
complex
Complex commonly refers to:
* Complexity, the behaviour of a system whose components interact in multiple ways so possible interactions are difficult to describe
** Complex system, a system composed of many components which may interact with each ...
structure in a compound object. So long as the ''reduction'' of non-mental properties to mental ones is in place, panpsychism is not strictly a form of property dualism; otherwise it is.
David Chalmers
David John Chalmers (; born 20 April 1966) is an Australian philosopher and cognitive scientist specializing in the areas of philosophy of mind and philosophy of language. He is a professor of philosophy and neural science at New York Universi ...
has expressed sympathy for panpsychism (or a modified variant, panprotopsychism) as a possible resolution to the
hard problem of consciousness, though he regards the
combination problem
In the philosophy of mind, panpsychism () is the view that the mind or a mindlike aspect is a fundamental and ubiquitous feature of reality. It is also described as a theory that "the mind is a fundamental feature of the world which exists thro ...
as an important obstacle for the theory.
Other philosophers who have taken interest in the view include
Thomas Nagel
Thomas Nagel (; born July 4, 1937) is an American philosopher. He is the University Professor of Philosophy and Law Emeritus at New York University, where he taught from 1980 to 2016. His main areas of philosophical interest are legal philosophy, ...
,
Galen Strawson
Galen John Strawson (born 1952) is a British analytic philosopher and literary critic who works primarily on philosophy of mind, metaphysics (including free will, panpsychism, the mind-body problem, and the self), John Locke, David Hume, ...
,
Timothy Sprigge
Timothy Lauro Squire Sprigge (14 January 1932 – 11 July 2007), usually cited as T. L. S. Sprigge, was a British idealist philosopher who spent the latter portion of his career at the University of Edinburgh, where he was Professor of Logic a ...
,
William Seager,
and
Philip Goff.
Other proponents
Saul Kripke
Kripke has a well-known argument for some kind of property dualism. Using the concept of
rigid designator
In modal logic and the philosophy of language, a term is said to be a rigid designator or absolute substantial term when it designates (picks out, denotes, refers to) the same thing in ''all possible worlds'' in which that thing exists. A designat ...
s, he states that if dualism is
logically possible, then it is the case.
Subjective idealism
Subjective idealism, proposed in the eighteenth century by
George Berkeley, is an ontic doctrine that directly opposes
materialism or
physicalism. It does not admit ontic property dualism, but does admit epistemic property dualism. It is rarely advocated by philosophers nowadays.
See also
*
Physicalism
*
Functionalism (philosophy of mind)
In philosophy of mind, functionalism is the thesis that mental states (beliefs, desires, being in pain, etc.) are constituted solely by their functional role, which means, their causal relations with other mental states, sensory inputs and behavio ...
*
Qualia
In philosophy of mind, qualia ( or ; singular form: quale) are defined as individual instances of subjective, conscious experience. The term ''qualia'' derives from the Latin neuter plural form (''qualia'') of the Latin adjective '' quālis'' () ...
* "
What Is It Like to Be a Bat?"
*
Explanatory gap
In the philosophy of mind and consciousness, the explanatory gap is the proposed difficulty that physicalist philosophies have in explaining how physical properties give rise to the way things feel subjectively when they are experienced. It is a ...
*
Chinese room
Notes
References
*
* Davidson, D. (1970) "Mental Events", in Actions and Events, Oxford: Clarendon Press, 1980
* Huxley, Thomas. (1874) "On the Hypothesis that Animals are Automata, and its History", ''The Fortnightly Review'', n.s. 16, pp. 555–580. Reprinted in ''Method and Results: Essays by Thomas H. Huxley'' (New York: D. Appleton and Company, 1898)
* Jackson, F. (1982) "Epiphenomenal Qualia", ''The Philosophical Quarterly'' 32: 127-136.
* Kim, Jaegwon. (1993) "Supervenience and Mind", Cambridge: Cambridge University Press.
* MacLaughlin, B. (1992) "The Rise and Fall of British Emergentism", in Beckerman, et al. (eds), Emergence or Reduction?, Berlin: De Gruyter.
* Mill, John Stuart (1843). "System of Logic". London: Longmans, Green, Reader, and Dyer.
th ed., 1872
External links
M. D. Robertson: Dualism vs. Materialism: A Response to Paul ChurchlandStanford Encyclopedia of Philosophy: DualismStanford Encyclopedia of Philosophy: EpiphenomenalismStanford Encyclopedia of Philosophy: Physicalism
{{DEFAULTSORT:Property Dualism
Metaphysics of mind
Dualism (philosophy of mind)
Theory of mind
Emergence