Rhetorical device

In rhetoric, a rhetorical device or resource of language is a technique that an author or speaker uses to convey to the listener or reader a meaning with the goal of persuading him or her towards considering a topic from a different perspective, using sentences designed to encourage or provoke a rational argument from an emotional display of a given perspective or action. Rhetorical devices can be used to evoke an emotional response in the audience, but that is not their primary purpose.

Logos is the use of logical ideas to appeal to the audience.

Pathos is an appeal to the audience's emotions.

Ethos describes the guiding tenets that characterize a community, nation, or ideology; it may also appeal to the author's credibility. It is an appeal based on the character of the speaker.

Kairos is an appeal to the timeliness of the argument.

Two common rhetorical devices are irony and metaphor.

The use of irony in rhetoric is primarily to convey to the audience an incongruity that is often used as a tool of humor in order to deprecate or ridicule an idea or course of action.

The use of metaphor in rhetoric is primarily to convey to the audience a new idea or meaning by linking it to an existing idea or meaning with which the audience is already familiar. By making the new concept appear to be linked to (or a type of) the old and familiar concept, the person using the metaphor hopes to help the audience understand the new concept.

An example of rhetorical device is this passage attributed to a speech by Abraham Lincoln about a political adversary in which Lincoln said that his adversary had "dived down deeper into the sea of knowledge and come up drier than any other man he knew".

This attributed quote uses a body of water as a metaphor for a body of knowledge with the ironical idea of someone who gained so little from his education that he achieved the impossible of jumping into a body of water and climbing back out without getting wet.

Sonic devices depend on sound.

Devices of altered signification shift the meaning of words.

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