An analogy is a comparison between two different things, in order to highlight some form of similarity.

Analogies are often used to explain new or complex concepts by showing the similarity between something familiar and something else.

Contents

1 Analogy types 2 Linguistic example 3 External links 4 References

Analogy types

• In linguistics, an analogy can be a spoken or textual comparison between two words (or sets of words) to highlight some form of semantical similarity between them. Linguistical analogies can be used to strengthen political and philosophical arguments, even when the semantical similarity is weak or non-existent (if crafted carefully for the audience).
• An analogy can also be the linguistical process that reduces word forms perceived as irregular by remaking them in the shape of more common forms that are governed by rules. For example, the English verb help once had the preterite holp and the past participle holpen. These obsolete forms have been discarded and replaced by helped by the power of analogy. However, irregular forms can sometimes be created by analogy; one example is the American English past tense form of "dive": "dove", formed on analogy with words such as drive-drove.
• Some types of analogies can have a precise mathematical formulation through the concept of isomorphism.
• In anatomy, two anatomical structures are considered to be analogous when they serve similar functions but are not evolutionarily related, such as the legs of vertebrates and the legs of insects. Analogous structures are the result of convergent evolution and should be contrasted with homologous structures.

Linguistic example

The United States-based SAT college entrance test includes "analogy" questions that ask for comparisons between analogies: A is to B as C is to what? For example:

Hand is to palm as foot is to ____?

Elephant is to piano keys as Kitten is to? (hint:Chinatown)

These questions are usually given in the format:

HAND : PALM : : FOOT : ____

External links

• Dictionary of the History of Ideas: http://etext.lib.virginia.edu/cgi-local/DHI/dhi.cgi?id=dv1-09 Analogy in Early Greek Thought
• Dictionary of the History of Ideas: http://etext.lib.virginia.edu/cgi-local/DHI/dhi.cgi?id=dv1-10 Analogy in Patristic and Medieval Thought

References

Holyoak, K.J. et. al. (1996). Mental Leaps: Analogy in Creative Thought. Cambridge, Massachusetts, The MIT Press.