Argument from fallacy

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Argument from fallacy is the formal fallacy of analyzing an argument and inferring that, since it contains a fallacy, its conclusion must be false. [1] It is also called argument to logic (argumentum ad logicam), the fallacy fallacy, [2] the fallacist's fallacy, [3] and the bad reasons fallacy. [4]

Contents

Form

An argument from fallacy has the following general argument form:

If P, then Q.
P is a fallacious argument.
Therefore, Q is false. [5]

Thus, it is a special case of denying the antecedent where the antecedent, rather than being a proposition that is false, is an entire argument that is fallacious. A fallacious argument, just as with a false antecedent, can still have a consequent that happens to be true. The fallacy is in concluding the consequent of a fallacious argument has to be false.

That the argument is fallacious only means that the argument cannot succeed in proving its consequent. [6] But showing how one argument in a complex thesis is fallaciously reasoned does not necessarily invalidate its conclusion if that conclusion is not dependent on the fallacy.

Examples

Alice: All cats are animals. Ginger is an animal. Therefore, Ginger is a cat.
Bob: You have just fallaciously affirmed the consequent. You are incorrect. Therefore, Ginger is not a cat.

Alice: I speak English. Therefore, I am English.
Bob: Americans and Canadians, among others, speak English too. By assuming that speaking English and being English always go together, you have just committed the package-deal fallacy. You are incorrect. Therefore, you are not English.

Both of Bob's rebuttals are arguments from fallacy. Ginger may or may not be a cat, and Alice may or may not be English. The fact that Alice's argument was fallacious is not, in itself, proof that her conclusion is false.

Charlie: Bob's argument that Ginger is not a cat is fallacious. Therefore, Ginger absolutely must be a cat.

That one can invoke the argument from fallacy against a position does not prove one's own position either, as this would also be an argument from fallacy, as is the case in Charlie's argument.

Further

Argumentum ad logicam can be used as an ad hominem appeal: by impugning the opponent's credibility or good faith, it can be used to sway the audience by undermining the speaker rather than by addressing the speaker's argument. [3]

William Lycan identifies the fallacy fallacy as the fallacy "of imputing fallaciousness to a view with which one disagrees but without doing anything to show that the view rests on any error of reasoning". Unlike ordinary fallacy fallacies, which reason from an argument's fallaciousness to its conclusion's falsehood, the kind of argument Lycan has in mind treats another argument's fallaciousness as obvious without first demonstrating that any fallacy at all is present. Thus in some contexts it may be a form of begging the question, [7] and it is also a special case of ad lapidem.

See also

Related Research Articles

In propositional logic, affirming the consequent is a formal fallacy that is committed when, in the context of an indicative conditional statement, it is stated that because the consequent is true, therefore the antecedent is true. It takes on the following form:

Ad hominem, short for argumentum ad hominem, refers to several types of arguments that are usually fallacious. Often currently this term refers to a rhetorical strategy where the speaker attacks the character, motive, or some other attribute of the person making an argument rather than the substance of the argument itself. This avoids genuine debate by creating a diversion often using a totally irrelevant, but often highly charged attribute of the opponent's character or background. The most common form of this fallacy is "A" makes a claim of "fact", to which "B" asserts that "A" has a personal trait, quality or physical attribute that is repugnant thereby going off-topic, and hence "B" concludes that "A" has their "fact" wrong – without ever addressing the point of the debate. Many contemporary politicians routinely use ad hominem attacks, some of which can be encapsulated to a derogatory nickname for a political opponent used instead of political argumentation.

The relativist fallacy, also known as the subjectivist fallacy, is claiming that something is true for one person but not true for someone else, when in fact that thing is an objective fact. The fallacy rests on the law of noncontradiction. The fallacy applies only to objective facts, or what are alleged to be objective facts, rather than to facts about personal tastes or subjective experiences, and only to facts regarded in the same sense and at the same time.

<span class="mw-page-title-main">Argument from ignorance</span> Informal fallacy

Argument from ignorance, also known as appeal to ignorance, is a fallacy in informal logic. The fallacy is committed when one asserts that a proposition is true because it has not yet been proven false or a proposition is false because it has not yet been proven true. If a proposition has not yet been proven true, one is not entitled to conclude, solely on that basis, that it is false, and if a proposition has not yet been proven false, one is not entitled to conclude, solely on that basis, that it is true. Another way of expressing this is that a proposition is true only if proven true, and a proposition is false only if proven false. If no proof is offered, then the proposition can be called unproven, undecided, inconclusive, an open problem or a conjecture. In debates, appealing to ignorance is sometimes an attempt to shift the burden of proof. The term was likely coined by philosopher John Locke in the late 17th century.

In propositional logic, modus ponens, also known as modus ponendo ponens, implication elimination, or affirming the antecedent, is a deductive argument form and rule of inference. It can be summarized as "P implies Q.P is true. Therefore, Q must also be true."

In classical rhetoric and logic, begging the question or assuming the conclusion is an informal fallacy that occurs when an argument's premises assume the truth of the conclusion. Historically, begging the question refers to a fault in a dialectical argument in which the speaker assumes some premise that has not been demonstrated to be true. In modern usage, it has come to refer to an argument in which the premises assume the conclusion without supporting it. This makes it an example of circular reasoning.

<span class="mw-page-title-main">Fallacy</span> Argument that uses faulty reasoning

A fallacy is the use of invalid or otherwise faulty reasoning in the construction of an argument that may appear to be well-reasoned if unnoticed. The term was introduced in the Western intellectual tradition by the Aristotelian De Sophisticis Elenchis.

Deductive reasoning is the process of drawing valid inferences. An inference is valid if its conclusion follows logically from its premises, meaning that it is impossible for the premises to be true and the conclusion to be false. For example, the inference from the premises "all men are mortal" and "Socrates is a man" to the conclusion "Socrates is mortal" is deductively valid. An argument is sound if it is valid and all its premises are true. One approach defines deduction in terms of the intentions of the author: they have to intend for the premises to offer deductive support to the conclusion. With the help of this modification, it is possible to distinguish valid from invalid deductive reasoning: it is invalid if the author's belief about the deductive support is false, but even invalid deductive reasoning is a form of deductive reasoning.

Denying the antecedent is a formal fallacy of inferring the inverse from an original statement. Phrased another way, denying the antecedent occurs in the context of an indicative conditional statement and assumes that the negation of the antecedent implies the negation of the consequent. It is a type of mixed hypothetical syllogism that takes on the following form:

Appeal to consequences, also known as argumentum ad consequentiam, is an argument that concludes a hypothesis to be either true or false based on whether the premise leads to desirable or undesirable consequences. This is based on an appeal to emotion and is a type of informal fallacy, since the desirability of a premise's consequence does not make the premise true. Moreover, in categorizing consequences as either desirable or undesirable, such arguments inherently contain subjective points of view.

The association fallacy is a formal logical fallacy that asserts that properties of one thing must also be properties of another thing if both things belong to the same group. For example, a fallacious arguer may claim that "bears are animals, and bears are dangerous; therefore your dog, which is also an animal, must be dangerous."

<span class="mw-page-title-main">Logical reasoning</span> Process of drawing correct inferences

Logical reasoning is a mental activity that aims to arrive at a conclusion in a rigorous way. It happens in the form of inferences or arguments by starting from a set of premises and reasoning to a conclusion supported by these premises. The premises and the conclusion are propositions, i.e. true or false claims about what is the case. Together, they form an argument. Logical reasoning is norm-governed in the sense that it aims to formulate correct arguments that any rational person would find convincing. The main discipline studying logical reasoning is logic.

<span class="mw-page-title-main">Informal fallacy</span> Form of incorrect argument in natural language

Informal fallacies are a type of incorrect argument in natural language. The source of the error is not just due to the form of the argument, as is the case for formal fallacies, but can also be due to their content and context. Fallacies, despite being incorrect, usually appear to be correct and thereby can seduce people into accepting and using them. These misleading appearances are often connected to various aspects of natural language, such as ambiguous or vague expressions, or the assumption of implicit premises instead of making them explicit.

In logic and philosophy, a formal fallacy is a pattern of reasoning rendered invalid by a flaw in its logical structure. Propositional logic, for example, is concerned with the meanings of sentences and the relationships between them. It focuses on the role of logical operators, called propositional connectives, in determining whether a sentence is true. An error in the sequence will result in a deductive argument that is invalid. The argument itself could have true premises, but still have a false conclusion. Thus, a formal fallacy is a fallacy in which deduction goes wrong, and is no longer a logical process. This may not affect the truth of the conclusion, since validity and truth are separate in formal logic.

Logic is the formal science of using reason and is considered a branch of both philosophy and mathematics and to a lesser extent computer science. Logic investigates and classifies the structure of statements and arguments, both through the study of formal systems of inference and the study of arguments in natural language. The scope of logic can therefore be very large, ranging from core topics such as the study of fallacies and paradoxes, to specialized analyses of reasoning such as probability, correct reasoning, and arguments involving causality. One of the aims of logic is to identify the correct and incorrect inferences. Logicians study the criteria for the evaluation of arguments.

Appeal to the stone, also known as argumentum ad lapidem, is a logical fallacy that dismisses an argument as untrue or absurd. The dismissal is made by stating or reiterating that the argument is absurd, without providing further argumentation. This theory is closely tied to proof by assertion due to the lack of evidence behind the statement and its attempt to persuade without providing any evidence.

In argumentation theory, an argumentum ad populum is a fallacious argument which is based on claiming a truth or affirming something is good or correct because many people think so.

An argument from authority is a form of argument in which the opinion of an authority figure is used as evidence to support an argument.

References

  1. K. S. Pope (2003). "Common Logical Fallacies in Psychology: 26 Types & Examples". Fallacies & Pitfalls in Psychology.
  2. Burkle-Young, F. A.; Maley, S. (1997). The research guide for the digital age. University Press of America. p. 324. ISBN   978-0-7618-0779-7.
  3. 1 2 Fischer, D. H. (June 1970). "Fallacies of substantive distraction". Historians' fallacies: toward a logic of historical thought. Harper torchbooks (first ed.). New York: HarperCollins. p. 305. ISBN   978-0-06-131545-9. OCLC   185446787. The fallacist's fallacy consists in any of the following false propositions... 3. The appearance of a fallacy in an argument is an external sign of its author's depravity.
  4. Warburton, Nigel (2007). Thinking from A to Z. Routledge. p. 25. ISBN   978-0-4154-3371-6 . Retrieved 10 August 2013.
  5. Morge, M. (2008). "The Argument Clinic: A Baloney Detection Kit" (PDF). PhD Lunchtime Seminar. Dipartemento di Informatica, Pisa: 20. Retrieved 2010-06-09.



    c since A

    A is fallacious

    ¬c

  6. John Woods, The death of argument: fallacies in agent based reasoning, Springer 2004, pp. XXIII–XXV
  7. Lycan, William G. (1996). "Qualia Strictly So Called". Consciousness and experience (first ed.). Cambridge, Massachusetts: The MIT Press. p. 69. ISBN   0-262-12197-2.

Further reading