Physical determinism generally refers to the assertion of a deterministic physical universe (greater physical system). This holds that a complete description of the physical state of the world at any given time and a complete statement of the physical laws of nature together entail every truth as to what physical events happen after that time. Such a position includes nomological determinism, which holds that all future events are governed by the past or present according to all-encompassing deterministic laws.
The concept of physical determinism has also been used to denote the predictability of a physical system, although this usage is uncommon. Physical determinism can also be viewed as an observed phenomenon of our experience, or a thesis only relevant to mathematical models of physics and other physical sciences. Physical determinism has also been used as a specific deterministic hypothesis about human behavior. Although somewhat unrelated to its standard context, physical determinism has also been used in social engineering theory.
The notion of physical determinism takes its classical form in the ideas of Laplace, who posited (in agreement with the physics of his time) that an omniscient observer (called sometimes Laplace's demon) knowing with infinite precision the positions and velocities of every particle in the universe could predict the future entirely. Although such an omniscient observer is a hypothetical construct, and infinite precision exceeds the capacities of human measurement, the illustration is presented as a statement of what in principle would be possible if physical determinism were true, and so reduction to practice is not an issue.
Physical determinism is currently under heavy debate in modern science. For example, physical indeterminism has been proposed to accommodate various interpretations of quantum mechanics. Suggestions have also been made to reformulate the conception of determinism with respect to its application to physical law.
Physical determinism is related to the question of causal completeness of physics, which is synonymous with the weaker form of causal closure. This is the idea that every real event has a scientific explanation, that science need not search for explanations beyond itself. If causal completeness does not apply to everything in the universe, then the door is open to events that are not subject to physical law. For example, a relatively common view of mental events is that they are an epiphenomenon produced as a by-product of neurological activity, and without causal impact. In this case, only a failure of deterministic physical law would allow room for their causal significance.
A more modern formulation of physical determinism skirts the issue of causal completeness. It is based upon connections between 'events' supplied by a theory:
"a theory is deterministic if, and only if, given its state variables for some initial period, the theory logically determines a unique set of values for those variables for any other period."—Ernest Nagel, Alternative descriptions of physical state p. 292
This quote replaces the idea of 'cause-and-effect' with that of 'logical implication' according to one or another theory that connects events. In addition, an 'event' is related by the theory itself to formalized states described using the parameters defined by that theory. Thus, the details of interpretation are placed where they belong, fitted to the context in which the chosen theory applies. Using the definition of physical determinism above, the limitations of a theory to some particular domain of experience also limits the associated definition of 'physical determinism' to that same domain.
- Causal closure
- Epistemological pluralism
- Free will
- Mind–body problem
- Model-dependent realism
- Subject–object problem
- Swinburne,R. G. (1969). "Physical Determinism". Royal Institute of Philosophy Lectures 3: 155–168.
There is for every physical state at some earlier instant a set of conditions jointly sufficient for its occurrence.
- David Papineau (2002). Thinking About Consciousness. Oxford University Press. p. 240. ISBN 978-0-19-924382-2. Retrieved 6 February 2013.
...physical determinism (the doctrine that prior physical conditions alone are enough to determine later physical conditions)
- See for example Popper, K (1972). Of Clouds and Clocks: an approach to the rationality and the freedom of man, included in Objective Knowledge. Oxford Clarendon Press. p. 5.
He pointed out that at any rate we could not possibly claim to know, from experience, of anything like a perfect clock, or of anything even faintly approaching that absolute perfection which physical determinism assumed.See also Felix T Hong (2003). "Towards physical dynamic tolerance: an approach to resolve the conflict between free will and physical determinism". Biosystems 68 (2-3): 85 - 105. doi:10.1016/S0303-2647(02)00089-8.
Classical (physical) determinism is also widely accepted by physicists and philosophers.See also Robert C. Bishop (2003). "On Separating Predictability and Determinism". Erkenntnis 58 (2): 169.
The belief that any deterministic system is predictable has been part of our scientific traditions in some form from their beginnings through the twentieth century. This belief is persistent because of the power of the intuitions that lie behind the concept of physical determinism.See also Robert C Bishop (2011). "Chapter 4: Chaos, indeterminism, and free will (Subtleties Regarding Physical Determinism)". In Robert Kane, ed. The Oxford Handbook of Free Will: Second Edition (2nd ed.). Oxford University Press. p. 94. ISBN 0195399692.
However, our best physical theories are terribly ambiguous regarding the status of physical determinism. There are several examples of violations of UE (unique evolution) in classical physics and the fate of UE in the special and general theories of relativity is currently unclear. As noted earlier, there are both deterministic and indeterministic versions of quantum mechanics that are empirically equivalent to the best of our current knowledge.
- See for example Hoefer, Carl (Apr 1, 2008). "Causal Determinism". In Edward N. Zalta, ed. The Stanford Encyclopedia of Philosophy (Winter 2009 edition).
There is a long tradition of compatibilists arguing that freedom is fully compatible with physical determinism
- Nicholas Bunnin and Jiyuan Yu, ed. (2004). "physical determinism". The Blackwell Dictionary of Western Philosophy. doi:10.1111/b.9781405106795.2004.x. ISBN 9781405106795.
The development of modern science, especially physics, led many to think that physical determinism must be true. Science claims that its aim is to discover these objective laws. If we can provide a complete physical explanation at this time for one thing, we will be able to predict its future on the grounds of natural laws
- John Earman (31 August 1986). A Primer on Determinism. Springer. p. 9. ISBN 978-90-277-2240-9. Retrieved 6 February 2013.
If physical determinism holds and the antecedent state of the universe suffices to fix the future physical state, including all of our movements and thus all of our actions, then "all of our thoughts, feelings, and efforts can have no practical influence upon what happens in the world..."
- Louis de Broglie (1930). "Introduction à l'Étude de la Mécanique Ondulatoire (Recueil d'Exposés sur les Ondes et Corpuscules)". Bull. Amer. Math. Soc. 38: 292 (80).
Beginning with the celebrated statement of physical determinism by Laplace, the author traces the development of the causal idea in physics up to the time when the quantum mechanics began to render its previous strict interpretation doubtful
- Robert C Bishop (2011). "Chapter 4: Chaos, indeterminism, and free will". In Robert Kane, ed. The Oxford Handbook of Free Will: Second Edition (2nd ed.). Oxford University Press. p. 84. ISBN 0195399692.
all physical events are determined to occur according to physical laws
- J. R. Lucas (1970). The Freedom of the Will. Oxford Scholarship Online. pp. Chap 12 (Types of Determinism), Chap 16 (Physical Determinism), Chap 20 (Quantum Mechanics1). doi:10.1093/acprof:oso/9780198243434.001.0001. ISBN 9780198243434. Retrieved 15 February 2013.
Physical determinism is based on there being physical laws of nature, many of which have actually been discovered, and of whose truth we can reasonably hope to be quite certain, together with the claim that all other features of the world are dependent on physical factors... Physical determinism is easily the most important type of determinism today. It is the only one that poses a credible threat to freedom. None of the other sorts of determinism are convincing, even though it may be a little tricky to put one's finger precisely on the mistake. But physical determinism is frightening. The arguments for it are forceful... it remains both well supported and incompatible with freedom... Quantum mechanics suggests a metaphysics less materialist than that of Locke and Newton, and is itself less mechanistic than Newtonian mechanics... The importance of quantum mechanics for the freedom of the will is twofold: it requires us to form a concept of a physical system radically different from that of Newton and Locke, in which particles such as atoms and molecules obey certain laws, and it is possible to know the state of a physical system completely at one time; and it may establish a principle of physical indeterminism relevant to the behaviour of the human body.
- Judy Illes; Barbara J. Sahakian (7 April 2011). Oxford Handbook of Neuroethics. Oxford University Press. p. 156. ISBN 978-0-19-162091-1. Retrieved 7 February 2013.
From the 17th century onwards- and particularly with the success of Newtonian physics, as it was said before- a new concept of nature emerged, superseding the Aristotelian perspective. In this conception, the world is causally closed: every event is caused by another event of the same ontological kind, and there is no place for an event that would not be imprisoned in the causal network of the world. In short, every event in the world is caused, and caused and effects are of the same material nature, their interaction being regulated by the laws of nature. This is physical determinism or determinism tout court.
- John Haugeland (15 September 2000). Having Thought: Essays in the Metaphysics of Mind. Harvard University Press. p. 99. ISBN 978-0-674-00415-3. Retrieved 10 February 2013.
If we believed in strict determinism, we would say: The history of the world could not have been different (physically) at each moment. The apparent failure of physical determinism, however, makes the relevant special authority of the physical more difficult to express. The basic idea seems to be that all the alternatives that are left fundamentally undetermined by physics (such as quantum indeterminancies) are genuinely undetermined - that is, nothing else determines them in lieu of physical factors.
- Neil Campbell (1 December 2002). Freedom, Determinism, and Responsibility: Readings in Metaphysics. Prentice Hall. p. 154. ISBN 978-0-13-048517-5. Retrieved 10 February 2013.
...is much like the physical determinism of Laplace, represented in the first section of this book. According to this view, every event is caused to exist and to have the properties it does because of events that happened in the past. This principle, which Taylor calls "the thesis of causal determinism," has the implication that we cannot really deliberate about our actions, nor is it ever up to us what we do; for our actions are the result of chains of causation that started long before we ever existed.
- This definition is from Carl Ginet (1990). On Action. Cambridge University Press. p. 92. ISBN 052138818X.
- Vihvelin, Kadri (2011). "Arguments for Incompatibilism". In Edward N. Zalta. The Stanford Encyclopedia of Philosophy (Spring 2011 ed.).
At a first approximation, nomological determinism, is a contingent and empirical claim about the laws of nature: that they are deterministic rather than probabilistic, and that they are all-encompassing rather than limited in scope... The laws of nature are all-encompassing if deterministic or probabilistic laws apply to everything in the universe [nature], without any exceptions. If, on the other hand, some individuals or some parts of some individuals (e.g., the nonphysical minds of human beings) or some of the behaviors of some of the individuals (e.g., the free actions of human beings) do not fall under [are not subject to] either deterministic or probabilistic laws [of nature], then the laws [of nature] are not all-encompassing [don't apply to nature as a whole]. [bracketed text added for clarification]
- Steven W Horst (2011). Laws, Mind, and Free Will. MIT Press. p. 98. ISBN 0262015250.
More exactly, even if there are also some things in the sciences called "laws" that are probabilistic and/or limited in scope, so long as there is some set of laws that is both deterministic and all-encompassing, nomological determinism, as characterized by Vihvelin, is entailed by definition.
- Ferenc Huoranszki (2011). Freedom of the Will: A Conditional Analysis. Taylor & Francis. pp. 56, 94, 102. ISBN 978-0-415-87947-7. Retrieved 8 February 2013.
If the analysis or some amended version of it works, then our ability to do otherwise is unproblematically compatible with physical/nomological determinism... At some points in this and the previous chapter I have already indicated that the conditional analysis is not only an ad hoc attempt to reconcile free will with physical or nomological determinism... Some compatibilists claim that we are free and responsible even if physical-nomological determinism is true
- Varadaraja V. Raman (1 May 2009). Truth and Tension in Science and Religion. Beech River Books. pp. 67,71. ISBN 978-0-9793778-6-0. Retrieved 10 February 2013.
Determinism (more exactly, nomological determinism) refers to a particular feature of the world by which every event that occurs is the inevitable outcome of precisely operating physical laws on simple and complex systems... In a famous essay Pierre Simon de Laplace stated: An intelligence knowing, at any given instant of time, all forces acting in nature, as well as the momentary positions of all things of which the universe consists, would be able to comprehend the motions of the largest bodies of the world and those of the smallest atoms in one single formula, provided it were sufficiently powerful to subject all data to analysis... He believed that human beings do not have any free will. Our actions are conditioned by how our bodies respond to external stimuli. The impact of Laplace is evident here... The so called compatibilist view is that both physical determinism and psychological free will are possible.
- See for example John Raymond Smythies; Hartwig Kuhlenbeck (1965). Brain and Mind: Modern Concepts of the Nature of Mind. Taylor & Francis. p. 47. GGKEY:XH37UDEDB7K. Retrieved 10 February 2013.
But since, on Feigl's analysis, physical determinism is in no way affected it follows that we could still, in principle, predict every item of behaviour given only the physical facts, disregarding completely any conscious concomitants. The analogy would be to the case in which one was presented with a clockwork mechanism where one would obviously ignore any optical properties or effects that one might observe as quite irrelevant to the dynamics of the situation.
- Lavinia Gomez (2005). The Freud Wars: An Introduction To The Philosophy Of Psychoanalysis. Psychology Press. p. 183. ISBN 978-1-58391-711-4. Retrieved 10 February 2013.
Intentional causality is teleological, or purposive, whereas physical determinism is nomological, or law-based
- G. M. K. Hunt (June 1987). "Determinism, Predictability and Chaos" 47 (3). Oxford University Press. p. 129.
The thesis of physical determinism is often supported by an appeal to a mechanical view of the world. This mechanical view derives much of its support from an appeal to classical mechanics.
- Bernard d'. Espagnat (2006). On Physics and Philosophy. Princeton University Press. p. 317. ISBN 978-0-691-11964-9. Retrieved 14 February 2013.
- Joseph M. Boyle; Germain Gabriel Grisez; Olaf Tollefsen (1 January 1976). Free Choice: A Self-Referential Argument. University of Notre Dame Press. p. 59. ISBN 978-0-268-00940-3. Retrieved 10 February 2013.
Physical determinism can begin as a specific deterministic hypothesis about human behavior, which then seeks some support from its conformity with the wider scientific worldview. This form of physical determinism can be formulated by saying that no interpretive model in addition to the models used to account for other natural events and processes is required to account for human... Richard Brandt and Jaegwon Kim propose such a formulation of physical determinism: An explanation will be deterministic if and only if the inferential and nomological patterns found in the biological sciences are taken to be sufficient to explain human choice. Any instance of physical determinism of this type would be a hypothesis proposed to explain human choices.
- Marios Camhis (1979). Planning Theory and Philosophy. Tavistock Publications. p. 27. ISBN 978-0-422-76840-5. Retrieved 10 February 2013.
Ebenezer Howard's ideas are the midpoint in the line between nineteenth-century utopians and twentiether-century planners, and mark the gradual transformation of the rational-deductive ideal from socialist utopian to physical determinism (or blue-print-planning). Howard deduced from the goals of a 'healthy, natural and economic combination of town and country life' his ideal community of a town of 5,000 acres with a population of some 2,000.
- For a discussion, see Robert C. Solomon, Kathleen M. Higgins (2009). "Free will and determinism". The Big Questions: A Short Introduction to Philosophy (8th ed.). Cengage Learning. p. 232. ISBN 0495595152.
- Ernest Nagel (1999). "§V: Alternative descriptions of physical state". The Structure of Science: Problems in the Logic of Scientific Explanation (2nd ed.). Hackett. pp. 285–292. ISBN 0915144719.
- See for example, Sahotra Sarkar, Jessica Pfeifer (2006). "Physicalism: The causal impact argument". The Philosophy of Science: N-Z, Index. Taylor & Francis. p. 566. ISBN 041597710X.
- Robert C Bishop, Harald Atmanspacher (2011). "Chapter 5: The causal closure of physics and free will". In Robert Kane, ed. The Oxford Handbook of Free Will: Second Edition (2nd ed.). Oxford University Press. p. 101. ISBN 0195399692.