False analogy

A false analogy is an informal fallacy. It applies to inductive arguments. The fallacy is committed when an analogy is not strong enough to support the conclusion that is drawn.

Usually this fallacy is committed when one reasons that if two things, situations or cases are alike in some respects, then they would be alike in other respects too, without valid justification. One who makes a weak analogy or comparison is often said to be "comparing apples and oranges".

Basic Structure:

 Entity A has attributes a, b, c, and z. 
 Entity B has attributes a, b, c. 
 Therefore, entity B probably has attribute z also.

Evaluating an argument having this form requires a two-step procedure: (1) Identify the attributes a, b, c, . . . that the two entities A and B share, and (2) determine how the attribute z, mentioned in the conclusion, relates to the attributes a, b, c, . . . If some causal or systematic relation exists between z and a, b, or c, the argument is a strong inductive argument; otherwise, it is weak.

 Examples 

The following are examples of false analogies: 

 Amber’s dog is similar in many ways to Kyle’s cat. Both like being petted, they enjoy being around people, they beg for food at the dinner table, and they sleep with their owners. Amber’s dog loves to romp on the beach with Amber. Therefore, Kyle’s cat probably loves to romp on the beach with Kyle.

Related pages
 Moral equivalence

 References 

Category:Logical fallacies