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The genetic fallacy (also known as the fallacy of origins or fallacy of virtue) [1] is a fallacy of irrelevance in which arguments or information are dismissed or validated based solely on their source of origin rather than their content. In other words, a claim is ignored or given credibility based on its source rather than the claim itself.
The fallacy therefore fails to assess the claim on its merit. The first criterion of a good argument is that the premises must have bearing on the truth or falsity of the claim in question. [2] Genetic accounts of an issue may be true and may help illuminate the reasons why the issue has assumed its present form, but they are not conclusive in determining its merits. [3]
In The Oxford Companion to Philosophy (1995), it is asserted that the term originated in Morris Raphael Cohen and Ernest Nagel's book Logic and Scientific Method [4] (1934). However, in a book review published in The Nation in 1926, Mortimer J. Adler complained that The Story of Philosophy by Will Durant was guilty throughout of "the fallacy of genetic interpretation." Adler characterized the genetic fallacy generally as "the substitution of psychology for logic." [5]
From Attacking Faulty Reasoning by T. Edward Damer, Third Edition p. 36:
You're not going to wear a wedding ring, are you? Don't you know that the wedding ring originally symbolized ankle chains worn by women to prevent them from running away from their husbands? I would not have thought you would be a party to such a sexist practice.
There are numerous motives explaining why people choose to wear wedding rings, but it would be a fallacy to presume those who continue the tradition are promoting sexism.
Another example would be from How to Win Every Argument: The Use and Abuse of Logic (2006) by Madsen Pirie, p. 82:
The objections of the Council's new bus timetable come only from private property developers, and can be ignored.
As the author points out, private developers may well have legitimate and knowledgeable opinions on such a matter.
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Fallacies of definition are the various ways in which definitions can fail to explain terms. The phrase is used to suggest an analogy with an informal fallacy. Definitions may fail to have merit, because they: are overly broad, use obscure or ambiguous language, or contain circular reasoning; those are called fallacies of definition. Three major fallacies are: overly broad, overly narrow, and mutually exclusive definitions, a fourth is: incomprehensible definitions, and one of the most common is circular definitions.
In a slippery slope argument, a course of action is rejected because the slippery slope advocate believes it will lead to a chain reaction resulting in an undesirable end or ends. The core of the slippery slope argument is that a specific decision under debate is likely to result in unintended consequences. The strength of such an argument depends on whether the small step really is likely to lead to the effect. This is quantified in terms of what is known as the warrant. This type of argument is often used as a form of fearmongering in which the probable consequences of a given action are exaggerated in an attempt to scare the audience.
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.
Special pleading is an informal fallacy wherein one cites something as an exception to a general or universal principle, without justifying the special exception. It is the application of a double standard.
A faulty generalization is an informal fallacy wherein a conclusion is drawn about all or many instances of a phenomenon on the basis of one or a few instances of that phenomenon. It is similar to a proof by example in mathematics. It is an example of jumping to conclusions. For example, one may generalize about all people or all members of a group from what one knows about just one or a few people:
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."
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.
Trivial objections is an informal logical fallacy where irrelevant and sometimes frivolous objections are made to divert the attention away from the topic that is being discussed. This type of argument is called a "quibble" or "quillet". Trivial objections are a special case of red herring.
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.
Attacking Faulty Reasoning is a textbook on logical fallacies by T. Edward Damer that has been used for many years in a number of college courses on logic, critical thinking, argumentation, and philosophy. It explains 60 of the most commonly committed fallacies. Each of the fallacies is concisely defined and illustrated with several relevant examples. For each fallacy, the text gives suggestions about how to address or to "attack" the fallacy when it is encountered. The organization of the fallacies comes from the author’s own fallacy theory, which defines a fallacy as a violation of one of the five criteria of a good argument:
In logic and philosophy, a formal fallacy, deductive fallacy, logical fallacy or non sequitur is a pattern of reasoning rendered invalid by a flaw in its logical structure that can neatly be expressed in a standard logic system, for example propositional logic. It is defined as 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 where 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.
An appeal to nature is an argument or rhetorical tactic in which it is proposed that "a thing is good because it is 'natural', or bad because it is 'unnatural'". It is generally considered to be a bad argument because the implicit (unstated) primary premise "What is natural is good" is typically irrelevant, having no cogent meaning in practice, or is an opinion instead of a fact.
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.
Informal logic encompasses the principles of logic and logical thought outside of a formal setting. However, the precise definition of "informal logic" is a matter of some dispute. Ralph H. Johnson and J. Anthony Blair define informal logic as "a branch of logic whose task is to develop non-formal standards, criteria, procedures for the analysis, interpretation, evaluation, criticism and construction of argumentation." This definition reflects what had been implicit in their practice and what others were doing in their informal logic texts.
Philosophy of logic is the area of philosophy that studies the scope and nature of logic. It investigates the philosophical problems raised by logic, such as the presuppositions often implicitly at work in theories of logic and in their application. This involves questions about how logic is to be defined and how different logical systems are connected to each other. It includes the study of the nature of the fundamental concepts used by logic and the relation of logic to other disciplines. According to a common characterization, philosophical logic is the part of the philosophy of logic that studies the application of logical methods to philosophical problems, often in the form of extended logical systems like modal logic. But other theorists draw the distinction between the philosophy of logic and philosophical logic differently or not at all. Metalogic is closely related to the philosophy of logic as the discipline investigating the properties of formal logical systems, like consistency and completeness.
Ralph Henry Johnson is a Canadian American philosopher, born in Detroit, Michigan. Johnson has been credited as one of the founding members of the informal logic movement in North America, along with J. Anthony Blair who co-published one of the movement's most influential texts, Logical Self-Defense, with Johnson. Alongside its founder, Blair, Johnson co-directed the Centre for Research in Reasoning, Argumentation, and Rhetoric at the University of Windsor. As Johnson and Blair write in the preface to the newest edition of Logical Self-Defense on the influential nature of the text:
"We might note that the theoretical perspective introduced in Logical Self-Defense has proved quite influential among textbook authors. It is to be found in modified form in A Practical Study of Argument by Trudy Govier, in Attacking Faulty Reasoning by T. Edward Damer, in Logic in Everyday Life and Open Minds and Everyday Reasoning by Zachary Seech, in Thinking Logically by James B. Freeman, and in Good Reasoning Matters by Leo Groarke and Christopher W. Tindale."
In argumentation theory, an argumentum ad populum is a fallacious argument which is based on claiming a truth or affirming something is good because many people think so.
