This article needs additional citations for verification .(April 2021) |
An argument from anecdote is an informal logical fallacy, when an anecdote is used to draw an improper logical conclusion. The fallacy can take many forms, such as cherry picking, hasty generalization, proof by assertion, and so on. [1]
The fallacy does not mean that every single instance of sense data or testimony must be considered a fallacy, only that anecdotal evidence, when improperly used in logic, results in a fallacy. Since anecdotal evidence can result in different kinds of logical fallacies, it is important to understand when this fallacy is being used and how it is being used.
The most common form of the fallacy is the use of anecdotes to create a fallacy of Hasty Generalization. Language surrounding the fallacy must indicate a logical conclusion, and includes absolute statements such as "every", "all", and so forth.
However, other forms of the fallacy exist. For instance, a person citing a myth or made-up story as evidence is engaging in proof by assertion. This is because, if the anecdote is fictional, it is not logically part of the argument. All that is left is the assertion that the argument is true, and it is thus the proof by assertion fallacy.
The Cherry-Picking fallacy can occur within the Anecdotal fallacy if an example is used but it is not representative of the average occurrence of such a thing.
Post Hoc Ergo Propter Hoc is another fallacy that is often paired with anecdotes.
"I was stung by a bee, so I know that therefore, all bees sting and all bees are aggressive."
This is an example of an anecdotal fallacy and hasty generalization, because a singular personal experience is being made to generalize to all bees.
This can be contrasted with another statement which is not fallacious:
"I was stung by a bee, some bees sting."
This statement is not fallacious because no logical claims were made about the experience (no use of terms like "therefore" and "all), and because the conclusion drawn from the experience was limited in scope and breadth to that particular experience.
An example of anecdotal evidence within the cherry-picking fallacy would be
I knocked a hornet's nest down once, but I wasn't stung. Therefore, hornets don't sting.
While it is possible to knock down a hornet's nest and not be stung, most people who knock down a hornet's nest will be stung. Here, the person draws the logical conclusion that, because of this singular experience (which is not representative of the average experience), hornets do not sting.
An example of anecdotal evidence within a proof by assertion fallacy would be as follows:
"I was reading a novel where it said that bees don't sting, therefore bees do not sting."
Since the anecdote here cited is admittedly fictional, it cannot be used as evidence. Since it cannot be used as evidence, there is no evidence and all that is left is just an assertion, thus proof by assertion. This can also be applied to anecdotal evidence with no attributable source, such as urban legends, myths, folk sayings and folklore.
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. 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 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.
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.
The genetic fallacy 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.
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:
Argument from fallacy is the formal fallacy of analyzing an argument and inferring that, since it contains a fallacy, its conclusion must be false. It is also called argument to logic, the fallacy fallacy, the fallacist's fallacy, and the bad reasons fallacy.
Cherry picking, suppressing evidence, or the fallacy of incomplete evidence is the act of pointing to individual cases or data that seem to confirm a particular position while ignoring a significant portion of related and similar cases or data that may contradict that position. Cherry picking may be committed intentionally or unintentionally.
Inductive reasoning is any of various methods of reasoning in which broad generalizations or principles are derived from a body of observations. This article is concerned with the inductive reasoning other than deductive reasoning, where the conclusion of a deductive argument is certain given the premises are correct; in contrast, the truth of the conclusion of an inductive argument is at best probable, based upon the evidence given.
Anecdotal evidence is evidence based only on personal observation, collected in a casual or non-systematic manner.
The formal fallacy of affirming a disjunct also known as the fallacy of the alternative disjunct or a false exclusionary disjunct occurs when a deductive argument takes the following logical form:
The fallacy of converse accident is an informal fallacy that can occur in a statistical syllogism, when a rule that applies only to an exceptional case is wrongly applied to all cases in general.
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, 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 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.
In logic and mathematics, proof by example is a logical fallacy whereby the validity of a statement is illustrated through one or more examples or cases—rather than a full-fledged proof.
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.
An argument is a series of sentences, statements, or propositions some of which are called premises and one is the conclusion. The purpose of an argument is to give reasons for one's conclusion via justification, explanation, and/or persuasion.
The invincible ignorance fallacy, also known as argument by pigheadedness, is a deductive fallacy of circularity where the person in question simply refuses to believe the argument, ignoring any evidence given. It is not so much a fallacious tactic in argument as it is a refusal to argue in the proper sense of the word. The method used in this fallacy is either to make assertions with no consideration of objections or to simply dismiss objections by calling them excuses, conjecture, anecdotal, etc. or saying that they are proof of nothing, all without actually demonstrating how the objections fit these terms. It is similar to the ad lapidem fallacy, in which the person rejects all the evidence and logic presented, without providing any evidence or logic that could lead to a different conclusion.
An argument from authority, also called an appeal to authority, or argumentum ad verecundiam, is a form of argument in which the opinion of an influential figure is used as evidence to support an argument.