An analogy is a comparison which takes the form "A is to B as C is to D." The relationship of A and B is compared to the relationship of C and D. While the analogy is a rather weak argument, since it can be used to support even the most absurd assertions, it can be emotionally persuasive when carefully constructed and extended in writing.


From simple analogies, we notice the most important thing about analogies: their parallel construction.

Example: A gun is to hunting as a pen is to writing.

While the analogy compares two quite different acts, it does so in a parallel construction, providing the object used, and the activity in which it is used. We would not say autumn is to hunting as a pen is to writing, since the constructions are not parallel; autumn is not an object used in hunting.

Persuasive Function

Making the analogy parallel is the first, and easiest, step in making an analogy. The second step, proving a point by it, is a bit trickier. The comparison above, of writing to hunting, might seem at first to be useless. However, if we were composing an advertisement for writing utensils to be placed in a hunting magazine, it might be profitable to convince hunters that a good pen is as important to writing as a good gun is to hunting. The close emotional attachment of hunters to hunting would be therefore used to sell ink pens.

Limits of Persuasive Function

The flexibility of analogies should be apparent; we can use any parallel comparison we wish to make any point we wish. The analogy's drawbacks should also be apparent: the fact that analogies can be used to prove any assertion, regardless of its truth, undermines their credibility.

Descriptive Function

Analogies are persuasive, even when used as simple description; by our choice of the things we compare, we communicate our feelings about them. The descriptive analogy can be quite useful. We can describe an object, person, or situation which may be unfamiliar to readers by comparing it to a familiar one. For example, we might describe a foreign culture in this way:

Cinco de Mayo, the anniversary of Mexico's independence from Spain, is an occasion of elaborate parades, wild parties, and tons of fireworks. It is much like our own Independence Day, 'The Fourth of July,' with its traditional town pageants, family get-togethers, and our own pyro-technic displays.

Notice the parallel construction of the comparison: in each case the name of the holiday is accompanied by three of its characteristics, which are similar, and offered in parallel order: parades and pageants, parties and get-togethers, fireworks and pyro-technic displays.


Analogies may be as long and elaborate or as short and concise as we wish them to be. In any case, they are best used to communicate our feeling about the things compared; we should not deceive ourselves that they are capable of proving a point beyond argument.


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