Chiasmus is a figure of speech in which words, grammatical constructions, or concepts are repeated in reverse order, in the same or a modified form. In other words, the clauses display inverted parallelism. Chiasmus was particularly popular both in Greek and in Latin literature, where it was used to articulate the balance of order within the text. As a popular example, many long and complex chiasmi have been found in Shakespeare and the Greek and Hebrew texts of the Bible.
In classic rhetoric, this figure of speech can be differentiated from an antimetabole, which is repetition of words in successive clauses in grammatical order. In a chiasmus, there is no recurrence of the same two terms. When chiasmus is applied to entire passages or writings, it is called a chiastic structure. Some examples of chiasmus are, "Never let a fool kiss You or a kiss fool you" by Mardy Grothe, "Do I love you because you're beautiful? Or are you beautiful because I love you?" by Oscar Hammerstein, and "They don't care about how much you know until they know how much you care" by Jim Calhoun.
Chiasmus is a figure of speech by which the order of the terms in the first of two parallel clauses is reversed in the second. This may involve a repetition of the same words or just a reversed parallel between two corresponding pairs of ideas.
Readers don't need to write but writers do need to read.