What literary device is primarily used to create comparisons in writing?

The literary device primarily used to create comparisons in writing is metaphor. A metaphor directly states that one thing is another, thereby drawing an implicit comparison between two different concepts to highlight similarities. For example, saying "time is a thief" suggests that time can steal moments from us, creating a vivid image and depth of meaning without using "like" or "as," which would characterize a simile.

This device enhances the reader's understanding by encouraging them to think critically about the relationship between two seemingly different elements. While similes also provide comparisons, they do so explicitly by using "like" or "as," making them a different form of comparison. Additionally, alliteration focuses on the repetition of initial consonant sounds and does not serve the function of comparison, while onomatopoeia relates to words that imitate sounds and is unrelated to comparison. Thus, metaphor stands out as the primary device for drawing complex and layered comparisons in literature.