Self-refuting idea

Self-refuting ideas are ideas or statements whose falsehood is a logical consequence of the act or situation of holding them to be true. Many ideas are accused by their detractors of being self-refuting, and such accusations are therefore almost always controversial, with defenders claiming that the idea is being misunderstood or that the argument is invalid. For these reasons, none of the ideas below are unambiguously or incontrovertibly self-refuting. These ideas are often used as axioms, which are definitions taken to be true (tautological assumptions), and cannot be used to test themselves, for doing so would lead to only two consequences: consistency (circular reasoning) or exception (self contradiction). It is important to know that the conclusion of an argument that is self-refuting is not necessarily false, since it could be supported by another, more valid, argument.

Variations

Directly self-denying statements

The Epimenides paradox is a statement of the form "this statement is false". Such statements troubled philosophers, especially when there was a serious attempt to formalize the foundations of logic. Bertrand Russell developed his "Theory of Types" to formalize a set of rules that would prevent such statements (more formally Russell's paradox) being made in symbolic logic. This work has led to the modern formulation of axiomatic set theory. While Russell's formalization didn't contain such paradoxes, Kurt Gödel showed that it must contain independent statements. Any logical system that is rich enough to contain elementary arithmetic contains at least one proposition whose interpretation is "this proposition is unprovable" (from within the logical system concerned), and hence no such system can be both complete and consistent.

Indirectly self-denying statements or "fallacy of the stolen concept"

Objectivists define the fallacy of the stolen concept: the act of using a concept while ignoring, contradicting or denying the validity of the concepts on which it logically and genetically depends. An example of the stolen concept fallacy is anarchist Pierre-Joseph Proudhon's assertion, "All property is theft".

While discussing the hierarchical nature of knowledge, Nathaniel Branden states, "Theft" is a concept that logically and genetically depends on the antecedent concept of "rightfully owned property"—and refers to the act of taking that property without the owner's consent. If no property is rightfully owned, that is, if nothing is property, there can be no such concept as "theft." Thus, the statement "All property is theft" has an internal contradiction: to use the concept "theft" while denying the validity of the concept of "property," is to use "theft" as a concept to which one has no logical right—that is, as a stolen concept.

Others have said the slogan is not an instance of the stolen concept fallacy under Proudhon's intended meaning. Proudhon used the term "property" with reference to claimed ownership in land, factories, etc. He believed such claims were illegitimate, and thus a form of theft from the commons. Proudhon explicitly states that the phrase "property is theft" is analogous to the phrase "slavery is murder". According to Proudhon, the slave, though biologically alive, is clearly in a sense "murdered". The "theft" in in his terminology does not refer to ownership any more than the "murder" refers directly to physiological death, but rather both are meant as terms to represent a denial of specific rights. [3] Others point out that the difference between the two examples is that "slavery is murder," unlike "property is theft," does not make a statement that denies the validity of one of the concepts it utilizes.

Examples

Brain in a Vat

Brain in a vat stands for any thought experiment in philosophy which posits that the world one experiences could in principle not be real (one could actually be a brain in a vat inside a laboratory, receiving electrical input identical to that which would be coming from the nervous system). This is notably similar to Descartes's evil daemon or to the dream argument. Sometimes it is also related to the different but somewhat similar question regarding whether we could be living inside a computer simulation. Philosopher Hilary Putnam claims that the thought experiment is inconsistent on the grounds that a brain in a vat could not have the sort of history and interaction with the world that would allow its thoughts or words to be about the vat that it is in. In other words, if any brain stated "I am a brain in a vat", it would always be stating a falsehood. This rebuttal is not universally accepted.

Determinism

It can be argued that to assert determinism as a rational claim in a debate is doubly self-defeating.

1. To count as rational, a belief must be freely chosen, which according to the determinist is impossible
2. Any kind of debate seems to be posited on the idea that the parties involved are trying to change each others minds.

Both arguments can be countered , for instance:

1. A belief is freely chosen if it is chosen without duress (according to compatibilism).
2. Determinism doesn't assert that people never change their minds, only that such changes are necessitated by causes. If someone changes their mind as the result of hearing an argument, that was a cause.

One can also consider a deterministic computer algorithm which is able to make a rational conclusion, such as a mathematical calculation or fingerprint identification.

Ethical Egoism

It has been argued that extreme ethical egoism is self-defeating. Faced with a situation of limited resources, egoists would consume as much of the resource as they could, making the overall situation worse for everybody. Egoists rejoin that if the situation becomes worse for everybody, that would include the egoist, so it is not in fact in their rational self-interest to take things to such extremes.

Eliminative materialism

The philosopher Mary Midgley claims the idea that "nothing exists except matter" is also self-refuting because if it were true neither it, nor any other idea, would exist, and similarly that an argument to that effect would be self-refuting because it would deny its own existence.

Several other philosophers argue that Eliminative materialism is self-refuting

However, other forms of materialism may escape this kind of argument because, rather than eliminating the mental, they seek to identify it with, or reduce it to, the material.. For instance, identity theorists such as J. J. C. Smart, Ullin Place and E. G. Boring claim that ideas exist materially as patterns of neural structure and activity.

Epimenides paradox

The first notable self-refuting idea is the Epimenides paradox, a statement attributed to Epimenides, a Cretan philosopher, that "All Cretans are Liars". Interpreted (for the present purpose) as meaning "no Cretan ever speaks the truth" this cannot be true if uttered by a Cretan. For the purpose of creating a self-refuting statement, this paradox might be better stated as "I am lying." This is because the first statement does not, if false, necessarily mean that the speaker is telling the truth (the third option being "some Cretans do not speak the truth"). The second statement has no third alternative—the speaker's statement is either true or false.

Evolutionary Naturalism

This is a particularly contentious proposal: Alvin Plantinga argues in his Evolutionary argument against naturalism that the combination of Naturalism and Evolution is "in a certain interesting way self-defeating" because if it were true there would be insufficient grounds to believe that human cognitive faculties are reliable. This argument has been supported and criticised by a variety of thinkers.

First-cause arguments

First cause arguments are described as self-refuting. For example, the philosopher Theodore Schick suggests that an argument by Thomas Aquinas can be formulated in the following terms:

1. Everything is caused by something other than itself
2. Therefore the universe was caused by something other than itself.
3. The string of causes cannot be infinitely long.
4. If the string of causes cannot be infinitely long, there must be a first cause.
5. Therefore, there must be a first cause, namely a divine entity.

– and suggests that this is self-refuting because "if everything has a cause other than itself, then god must have a cause other than himself. But if god has a cause other than himself, he cannot be the first cause. So if the first premise is true, the conclusion must be false."

Schick's argument may be refuted by restating the first premise as "Everything that is observable in the natural universe is caused by something other than itself", or that "Everything that began to exist has a cause."

Foundationalism

The Philosopher Anthony Kenny argues that the idea, "common to theists like Aquinas and Descartes and to an atheist like Russell" that "Rational belief [is] either self-evident or based directly or indirectly on what is evident" (which he termed "foundationalism" following Plantinga) is self-refuting on the basis that this idea is itself neither self-evident nor based directly or indirectly on what is evident and that the same applies to other formulations of such foundationalism. However, the self-evident impossibility of infinite regress can be offered as a justification for foundationalism. Following the identification of problems with "naive foundationalism", the term is now often used re-defined to focus on incorrigible beliefs (modern foundationalism), or basic beliefs (reformed foundationalism).

Relativism

It is often asserted that relativism about truth must be applied to itself. The cruder form of the argument concludes that since the relativist is asserting relativism as an absolute truth, it leads to a contradiction. Relativists often rejoin that in fact relativism is only relatively true, leading to a subtler problem: the absolutist, the relativist's opponent, is perfectly entitled, by the relativist's own standards, to reject relativism. That is, the relativist's arguments can have no normative force over someone who has different basic beliefs.

Skepticism

Skeptics claim "nothing can be known". Can that claim itself be known, or is it self-refuting? One very old response to this problem is Academic skepticism: an exception is made for the skeptic's own claim. This leads to further debate about consistency and special pleading. Another response is to accept that "nothing can be known" cannot itself be known, so that it is not known whether anything is knowable or not. This is Pyrrhonic skepticism.

Scientism

The statement "no statements are true unless they can be proven scientifically", is claimed to be self-refuting insofar as it cannot be proven scientifically; the same goes for essentially similar views like "no statements are true unless they can be shown empirically to be true". (This kind of issue was a serious problem for logical positivism).

Solipsism

On the face of it, a statement of solipsism is — at least performatively — self-defeating, because a statement assumes another person to whom the statement is made. (That is to say, an unexpressed private belief in solipsism is not self-refuting). This, of course, assumes the solipsist would not communicate with a hallucination, even if just for self-amusement.

The solipsist can adopt the rather surreal maneuver of claiming that their interlocutor is in fact a figment of their imagination, but since their interlocutor knows they are not, they are not going to be convinced!

Verification- and falsification-principles

The statements "statements are meaningless unless they can be empirically verified" and "statements are meaningless unless they can be empirically falsified" are both claimed to be self-refuting on the basis that they can neither be empirically verified nor falsified

In logic

Self-refutation plays an important role in some inconsistency tolerant logics (e.g. paraconsistent logics and Direct Logic) that lack proof by contradiction. For example, the negation of a proposition can be proved by showing that the proposition infers its own negation. Likewise, it can be inferred that a proposition cannot be proved by (1) showing that a proof would infer the negation of the proposition or by (2) showing a proof would infer that the negation of the proposition can be proved.

Wittgenstein's Tractatus

The Tractatus Logico-Philosophicus is an unusual example of a self-refuting argument, in that Ludwig Wittgenstein explicitly admits to the issue at the end of the work:

"My propositions are elucidatory in this way: he who understands me finally recognizes them as senseless, when he has climbed out through them, on them, over them. (He must so to speak throw away the ladder, after he has climbed up on it)".

(6.54)

However, this idea can be solved in the sense that, even if the argument itself is self-refuting, the effects of the argument elicit understandings that go beyond the argument itself. Søren Kierkegaard describes it as such:

"[The reader] can understand that the understanding is a revocation--the understanding with him as the sole reader is indeed the revocation of the book. He can understand that to write a book and to revoke it is not the same as refraining from writing it, that to write a book that does not demand to be important for anyone is still not the same as letting it be unwritten." (Concluding Unscientific Postscript)

See also

• Contradiction
• Paradox
• Performative contradiction
• Self-defeating prophecy