The logical fallacy of accident, also called destroying the exception or a dicto simpliciter ad dictum secundum quid, is a deductive fallacy occurring in statistical syllogisms (an argument based on a generalization) when an exception to the generalization is ignored. A logical fallacy is an error in logical argument which is independent of the truth of the premises. ... There are several meanings for the word deduction: Natural deduction Deductive reasoning Deductions in terms of taxation, such as Itemized deductions Standard deduction See also: Logic Venn diagram Inductive reasoning Both statistics and the scientific method rely on both induction and deduction. ... A statistical syllogism is an inductive syllogism. ... Concept A is a generalization of concept B if and only if: every instance of concept B is also an instance of concept A; and there are instances of concept A which are not instances of concept B. Equivalently, A is a generalization of B if B is a specialization...

For instance:

1. Cars should never exceed the speed limit
2. Police cars are cars
3. Therefore, police cars should never exceed the speed limit

As a matter of fact the rule, cars should never exceed the speed limit, is only a general rule and police cars may be a valid exception.

Additionally:

1. Cutting people with a knife is a crime.
2. Surgeons cut people with knives.
3. Surgeons are criminals.

It is easy to construct fallacious arguments by applying general statements to specific incidents that are obviously exceptions.

Generalizations that are weak generally have more exceptions (the number of exceptions to the generalization need not be a minority of cases) and vice versa.

This fallacy may occur when we confuse generalizations ("some") for categorical statements ("always and everywhere"). It may be encouraged when no qualifying words like "some", "many", "rarely" etc. are used to mark the generalization. The word modifier applies to either the adjective or the adverb in a sentence. ...

For example:

Jews killed Jesus

The premise above could be used in an argument concluding that all Jews or current Jews should be responsible for Jesus' death. Qualifying the first term: This 11th-century portrait is one of many images of Jesus in which a halo with a cross is used. ... The major term is the predicate term of the conclusion of a categorical syllogism. ...

Some Jews killed Jesus

This premise may make it more obvious it is making an (extremely weak) generalization and not a categorical rule. The term could be made even more specific, such as "50-60 Jews in Judea living around 30 AD" from which it might be more difficult to attempt to draw a more wide-ranging conclusion.

Related inductive fallacies include: overwhelming exception, hasty generalization. See faulty generalization. The term induction has more than one meaning in the English language. ... Hasty generalization, also known as fallacy of insufficient statistics, fallacy of insufficient sample, fallacy of the lonely fact, leaping to a conclusion, hasty induction or secundum quid, is the logical fallacy of reaching an inductive generalization based on too little evidence. ... A faulty generalization, also known as an inductive fallacy, is any of several errors of inductive inference: Hasty generalization is the fallacy of examining just one or very few examples or studying a single case, and generalizing that to be representative of the whole class of objects or phenomena. ...

The opposing kind of dicto simpliciter fallacy is the converse accident. The introduction of this article does not provide enough context for readers unfamiliar with the subject. ... The logical fallacy of converse accident (also called reverse accident, destroying the exception or a dicto secundum quid ad dictum simpliciter) is a deductive fallacy that can occur in a statistical syllogism when an exception to a generalization is wrongly called for. ...

External links

• Bruce Thompon's fallacies: Accident
• Fallacy files: Accident
• Stephen's Guide: Accident