Metaphors state that two objects which seem to be different are actually the same. "He was a mule standing his ground" likens the man to a mule, indicating to the reader that he is stubborn. An implied metaphor does not come right out and make the comparison but instead suggests it more subtly, such as "he brayed his intention to stay." Here the reader understands the man is a mule since he "brayed," but the writer does not state the connection for the reader.
Indirect metaphors allow authors to express ideas in a more concise manner. They give the reader guidance regarding the message without a long-winded explanation. Because of the language, readers must determine the meaning, so writers must use caution to make certain the message received is the intended one.
All types of metaphor help writers convey ideas. They describe concepts and objects for which words do not currently exist, such as English author, Gerard Woodward's description of "the waggle-dance of a small forklift." Since they connect disparate concepts, writers also use indirect metaphors to create an element of surprise for a reader. This surprise reaction may result in humor or discomfort from the surreal relationship, helping a writer develop a specific emotional tone for the work.
Indirect metaphors depend on a knowledgeable reader. Readers who cannot see past the literal meaning in the language or are unfamiliar with the underlying allusions necessary for understanding will lose the message of the metaphor. For instance, a reader who thinks of a mule as a pack animal and does not associate the creature with stubbornness would not understand a "braying" connection. Obscure and confusing references detract from writing instead of enhancing it.