Core Concepts
Actualism Adequate Determinism Agent-Causality Alternative Possibilities Causa Sui Causal Closure Causalism Causality Certainty Chance Chance Not Direct Cause Chaos Theory The Cogito Model Compatibilism Complexity Comprehensive Compatibilism Conceptual Analysis Contingency Control Could Do Otherwise Creativity Default Responsibility De-liberation Determination Determination Fallacy Determinism Disambiguation Double Effect Either Way Emergent Determinism Epistemic Freedom Ethical Fallacy Experimental Philosophy Extreme Libertarianism Event Has Many Causes Frankfurt Cases Free Choice Freedom of Action "Free Will" Free Will Axiom Free Will in Antiquity Free Will Mechanisms Free Will Requirements Free Will Theorem Future Contingency Hard Incompatibilism Idea of Freedom Illusion of Determinism Illusionism Impossibilism Incompatibilism Indeterminacy Indeterminism Infinities Laplace's Demon Libertarianism Liberty of Indifference Libet Experiments Luck Master Argument Modest Libertarianism Moral Necessity Moral Responsibility Moral Sentiments Mysteries Naturalism Necessity Noise Non-Causality Nonlocality Origination Paradigm Case Possibilism Possibilities Pre-determinism Predictability Probability Pseudo-Problem Random When?/Where? Rational Fallacy Refutations Replay Responsibility Same Circumstances Scandal Science Advance Fallacy Second Thoughts Self-Determination Semicompatibilism Separability Soft Causality Special Relativity Standard Argument Supercompatibilism Superdeterminism Taxonomy Temporal Sequence Tertium Quid Torn Decision Two-Stage Models Ultimate Responsibility Uncertainty Up To Us Voluntarism What If Dennett and Kane Did Otherwise? Philosophers Mortimer Adler Rogers Albritton Alexander of Aphrodisias Samuel Alexander William Alston Anaximander G.E.M.Anscombe Anselm Louise Antony Thomas Aquinas Aristotle David Armstrong Harald Atmanspacher Robert Audi Augustine J.L.Austin A.J.Ayer Alexander Bain Mark Balaguer Jeffrey Barrett William Barrett William Belsham Henri Bergson George Berkeley Isaiah Berlin Richard J. Bernstein Bernard Berofsky Robert Bishop Max Black Susanne Bobzien Emil du Bois-Reymond Hilary Bok Laurence BonJour George Boole Émile Boutroux F.H.Bradley C.D.Broad Michael Burke Lawrence Cahoone C.A.Campbell Joseph Keim Campbell Rudolf Carnap Carneades Ernst Cassirer David Chalmers Roderick Chisholm Chrysippus Cicero Randolph Clarke Samuel Clarke Anthony Collins Antonella Corradini Diodorus Cronus Jonathan Dancy Donald Davidson Mario De Caro Democritus Daniel Dennett Jacques Derrida René Descartes Richard Double Fred Dretske John Dupré John Earman Laura Waddell Ekstrom Epictetus Epicurus Herbert Feigl Arthur Fine John Martin Fischer Frederic Fitch Owen Flanagan Luciano Floridi Philippa Foot Alfred Fouilleé Harry Frankfurt Richard L. Franklin Michael Frede Gottlob Frege Peter Geach Edmund Gettier Carl Ginet Alvin Goldman Gorgias Nicholas St. John Green H.Paul Grice Ian Hacking Ishtiyaque Haji Stuart Hampshire W.F.R.Hardie Sam Harris William Hasker R.M.Hare Georg W.F. Hegel Martin Heidegger Heraclitus R.E.Hobart Thomas Hobbes David Hodgson Shadsworth Hodgson Baron d'Holbach Ted Honderich Pamela Huby David Hume Ferenc Huoranszki William James Lord Kames Robert Kane Immanuel Kant Tomis Kapitan Walter Kaufmann Jaegwon Kim William King Hilary Kornblith Christine Korsgaard Saul Kripke Andrea Lavazza Christoph Lehner Keith Lehrer Gottfried Leibniz Jules Lequyer Leucippus Michael Levin George Henry Lewes C.I.Lewis David Lewis Peter Lipton C. Lloyd Morgan John Locke Michael Lockwood E. Jonathan Lowe John R. Lucas Lucretius Alasdair MacIntyre Ruth Barcan Marcus James Martineau Storrs McCall Hugh McCann Colin McGinn Michael McKenna Brian McLaughlin John McTaggart Paul E. Meehl Uwe Meixner Alfred Mele Trenton Merricks John Stuart Mill Dickinson Miller G.E.Moore Thomas Nagel Otto Neurath Friedrich Nietzsche John Norton P.H.Nowell-Smith Robert Nozick William of Ockham Timothy O'Connor Parmenides David F. Pears Charles Sanders Peirce Derk Pereboom Steven Pinker Plato Karl Popper Porphyry Huw Price H.A.Prichard Protagoras Hilary Putnam Willard van Orman Quine Frank Ramsey Ayn Rand Michael Rea Thomas Reid Charles Renouvier Nicholas Rescher C.W.Rietdijk Richard Rorty Josiah Royce Bertrand Russell Paul Russell Gilbert Ryle Jean-Paul Sartre Kenneth Sayre T.M.Scanlon Moritz Schlick Arthur Schopenhauer John Searle Wilfrid Sellars Alan Sidelle Ted Sider Henry Sidgwick Walter Sinnott-Armstrong J.J.C.Smart Saul Smilansky Michael Smith Baruch Spinoza L. Susan Stebbing Isabelle Stengers George F. Stout Galen Strawson Peter Strawson Eleonore Stump Francisco Suárez Richard Taylor Kevin Timpe Mark Twain Peter Unger Peter van Inwagen Manuel Vargas John Venn Kadri Vihvelin Voltaire G.H. von Wright David Foster Wallace R. Jay Wallace W.G.Ward Ted Warfield Roy Weatherford C.F. von Weizsäcker William Whewell Alfred North Whitehead David Widerker David Wiggins Bernard Williams Timothy Williamson Ludwig Wittgenstein Susan Wolf Scientists Michael Arbib Walter Baade Bernard Baars Leslie Ballentine Gregory Bateson John S. Bell Mara Beller Charles Bennett Ludwig von Bertalanffy Susan Blackmore Margaret Boden David Bohm Niels Bohr Ludwig Boltzmann Emile Borel Max Born Satyendra Nath Bose Walther Bothe Hans Briegel Leon Brillouin Stephen Brush Henry Thomas Buckle S. H. Burbury Donald Campbell Anthony Cashmore Eric Chaisson Gregory Chaitin Jean-Pierre Changeux Arthur Holly Compton John Conway John Cramer Francis Crick E. P. 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Necessity
Necessity is the idea that everything that has ever happened and ever will happen is necessary, and can not be otherwise. Necessity is often opposed to chance and contingency. In a necessary world there is no chance. Everything that happens is necessitated.
The great atomist Leucippus stated the first dogma of determinism, an absolute necessity.
"Nothing occurs at random, but everything for a reason and by necessity."
But we must distinguish between this claim of physical necessity and the simpler logical necessity of formal systems.
Aristotle's logic defended the logical necessity that only one of two contradictory statements can be true, and the other false. Diodorus Cronus developed the Master Argument to show that only one answer to a question about a future event can be true. Either Yes or No. This led to the Megarian idea of actualism, that there is no future contingency and only one possible future.
Diodorus' paradox was the result of the principle of bivalence or the law of the excluded middle. Only one of two logically contradictory statements can be necessarily true. Aristotle solved the paradox by saying that the truth of statements about the future is contingent on the actual future, as follows,
"A sea battle must either take place tomorrow or not,The major founder of Stoicism, Chrysippus, took the edge off strict necessity. Like Democritus, Aristotle, and Epicurus before him, Chrysippus wanted to strengthen the argument for moral responsibility, in particular defending it from Aristotle's and Epicurus's indeterminate chance causes. Whereas the past is unchangeable, Chrysippus argued that some future events that are possible do not occur by necessity from past external factors alone, but might depend on us. We have a choice to assent or not to assent to an action. Later, Leibniz distinguished two forms of necessity, necessary necessity and contingent necessity. This basically distinguished logical necessity from physical (or empirical) necessity. In the eighteenth century debates about freedom and necessity (free will versus determinism), many thinkers distinguished a moral necessity from physical necessity. Moral necessity describes the will being (self) determined by an agent's reasons and motives. Extreme libertarians insisted on a will that was not determined by reasons, fearing that this implies pre-determinism, which it does not. In two-stage models of free will, indeterminism in the generation of alternative possibilities for action breaks the causal chain of determinism.
Chance is regarded as inconsistent with logical determinism and with any limits on causal, physical or mechanical determinism.
Despite abundant evidence to the contrary, many philosophers deny that chance exists. If a single event is determined by chance, then indeterminism would be true, they say, and undermine the very possibility of certain knowledge. Some go to the extreme of saying that chance would make the state of the world totally independent of any earlier states, which is nonsense, but it shows how anxious they are about chance.
Bertrand Russell said "The law of causation, according to which later events can theoretically be predicted by means of earlier events, has often been held to be a priori, a necessity of thought, a category without which science would not be possible." (Russell, External World p.179)
The core idea of indeterminism is closely related to the idea of causality. Indeterminism for some is simply an event without a cause. But we can have an adequate causality without strict determinism, which implies complete predictability of events and only one possible future.
An example of an event that is not strictly caused is one that depends on chance, like the flip of a coin. If the outcome is only probable, not certain, then the event can be said to have been caused by the coin flip, but the head or tails result was not predictable. So this causality, which recognizes prior events as causes, is undetermined and the result of chance alone.
We call this "soft" causality. Events are caused by prior (uncaused) events, but not determined by events earlier in the causal chain, which has been broken by the uncaused cause.
Necessity is critical for the question of free will. Strict necessity implies just one possible future. Chance means that the future is unpredictable. Chance allows alternative futures and the question becomes how the one actual present is realized from these potential alternatives.
The departure required from strict necessity is very slight compared to the miraculous ideas associated with the "causa sui" (self-caused cause) of the ancients.
Despite David Hume's critical attack on the necessity of causes, many philosophers embrace causality strongly. Some even connect it to the very possibility of logic and reason. And Hume himself strongly, if inconsistently, believed in necessity while denying causality. He said "'tis impossible to admit any medium betwixt chance and necessity."
Even in a world with chance, macroscopic objects are determined to an extraordinary degree. This is the basis for physical necessity. Newton's laws of motion are deterministic enough to send men to the moon and back. Our Cogito model of the Macro Mind is large enough to ignore quantum uncertainty for the purpose of the reasoning will. The neural system is robust enough to insure that mental decisions are reliably transmitted to our limbs. Our actions are determined by our thoughts. But our thoughts themselves are free. This means that our actions were not pre-determined from before we began thinking.
we see a world of
soft causality and adequate determinism
We call this kind of determinism (determined but not pre-determined) "adequate determinism." Physical determinism is adequate enough for us to predict eclipses for the next thousand years or more with extraordinary precision.
The presence of quantum uncertainty leads some philosophers to call the world indetermined. But indeterminism is misleading, with strong negative connotations, when most events are overwhelmingly "adequately determined."
There is no problem imagining that the three traditional mental faculties of reason - perception, conception, and comprehension - are for all practical purposes carried on deterministically in a physical brain where quantum events do not interfere with normal operations, unless the agent deliberately seeks to be original and creative.
There is also no problem imagining a role for chance in the brain in the form of quantum level noise. Noise can introduce random errors into stored memories. Noise could create random associations of ideas during memory recall which are the source of novel ideas.
Our Macro Mind needs the Micro Mind for the free action items and thoughts in an Agenda of alternative possibilities to be de-liberated by the will. Chance in the Micro Mind is the "free" in free will and the source of human creativity. The adequately determined Macro Mind is the "will" in free will that de-liberates, choosing actions for which we can be morally responsible.
[Necessity must be limited to its proper use in logic, and disambiguated from its close relatives causality, determinism, certainty, and predictability.]
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