In rhetoric, logos is a method of persuading someone using reason and logic. If you convince your grandpa that climate change is real by showing him scientific data, you're using logos.

Philosophers have used the term logos since ancient times. Aristotle was the first to define the word as "reasoned discourse," and considered it one of the major forms of persuasion. Christians adopted logos to mean "the word of God," and Jungian psychology labels the rational part of the human mind as logos. Logos is a Greek word meaning "word, discourse, or reason," and it's the root of logic.

Definitions of logos
  1. noun
    a rhetorical appeal to the audience's reason or rationality
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    type of:
    expressive style, style
    a way of expressing something (in language or art or music etc.) that is characteristic of a particular person or group of people or period
Word Family

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