How does Damon Knight use imagery in Creating Short Fiction?

In Part IV, Knight notes that a stage magician works his magic by illusion and sleight-of-hand. The magician brings the audience into his act and controls their reaction by his ability to build anticipation. The writer, in his own way, also uses illusions and tricks to engage his audience, the readers. The magician takes control of his audience in four ways: By taking advantage of their expectation to be controlled; by exhibiting a commanding presence; by his imagery—words and movements; and, by providing the audience with a focal point.