Accident (fallacy)

Last updated

The fallacy of accident (also called destroying the exception or a dicto simpliciter ad dictum secundum quid) is an informal fallacy and a deductively valid but unsound argument occurring in a statistical syllogism (an argument based on a generalization) when an exception to a rule of thumb [1] is ignored. It is one of the thirteen fallacies originally identified by Aristotle in Sophistical Refutations . The fallacy occurs when one attempts to apply a general rule to an irrelevant situation.

For example:

Cutting people with knives is a crime. →

Surgeons cut people with knives. →

Surgeons are criminals.


This fallacy may occur when limited generalizations ("some; sometimes and somewhere") are mixed with A-type categorical statements ("all; always and everywhere"), often when no quantifiers like "some" or "many" or qualifiers such as "rarely" are used to mark off what is or may be excepted in the generalization.

Related inductive fallacies include overwhelming exceptions and hasty generalizations. See faulty generalization.

The opposing kind of dicto simpliciter fallacy is the converse accident.

Notes

  1. "The Fallacy of Accident". The Fallacy Files.

Reference list


Related Research Articles

<span class="mw-page-title-main">False dilemma</span> Informal fallacy involving falsely limited alternatives

A false dilemma, also referred to as false dichotomy or false binary, is an informal fallacy based on a premise that erroneously limits what options are available. The source of the fallacy lies not in an invalid form of inference but in a false premise. This premise has the form of a disjunctive claim: it asserts that one among a number of alternatives must be true. This disjunction is problematic because it oversimplifies the choice by excluding viable alternatives, presenting the viewer with only two absolute choices when in fact, there could be many.

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 more or less synonymous with 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.

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.

Post hoc ergo propter hoc is an informal fallacy that states: "Since event Y followed event X, event Y must have been caused by event X." It is often shortened simply to post hoc fallacy. A logical fallacy of the questionable cause variety, it is subtly different from the fallacy cum hoc ergo propter hoc, in which two events occur simultaneously or the chronological ordering is insignificant or unknown. Post hoc is a logical fallacy in which one event seems to be the cause of a later event because it occurred earlier.

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 term Inductive reasoning is used to refer to any method 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.

<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 called logic.

The fallacy of four terms is the formal fallacy that occurs when a syllogism has four terms rather than the requisite three, rendering it invalid.

A statistical syllogism is a non-deductive syllogism. It argues, using inductive reasoning, from a generalization true for the most part to a particular case.

Secundum quid is a type of informal fallacy that occurs when the arguer fails to recognize the difference between rules of thumb and categorical propositions, rules that hold true universally.

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.

<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, 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.

Converse may refer to:

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.

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.