Metaphors juxtapose two nouns in a way that positively asserts their similarities, while not disconfirming their dissimilarities. For example:
War is Hell.
Metaphors contain four key elements: two are the items being compared, two are they in which they relate.
The two comparison elements are:
Tenor: topic of the metaphor (war)
Vehicle: what the tenor is described in terms of (hell)
The two relations are:
Ground: set of similarities between the tenor and the vehicle (both are terrible places)
Tension: set of dissimilarities between the two (hell does not exist, war does)
The conjecture is that the key similarity between war and hell, is that they’re both to be seemingly avoided; the key dissimilarity is that war is a very real thing humans have to deal with, and hell is an imagined element of religious fiction (depending on the person).
Of the various theories proposed to explain how metaphors work, the traditional views highlight either the ways the tenor and vehicle are similar or different. As applied to the metaphor, “Abused children are walking time-bombs”:
Comparison View: underscores the similarity between elements: both are subject to explosive activity
Anomaly View: emphasizes the dissimilarity: adults who’ve been abused don’t have C4 and activating wires in their bodies
The “Class Inclusion” view emphasizes that the elements fall into the same types of categorical classifications. By saying “My co-worker is an iceberg,” the implication is made that said person belongs to a category of objects characterized by an utter lack of warmth, extreme rigidity, and the ability to produce a massively chilling effect on items within the immediate environment.
Reading metaphors change the perception of both elements, and thus enhance the understanding of language and the world in which language thrives, but metaphors can be connotatively positive as opposed to the examples I’ve given:
Her eyes are diamonds that shine beautifully.
Similes are different from metaphors because they introduce the word “like” or “as” into the phraseology:
Her complexion is like silk, and her eyes are as beautiful as the morning sky.
To experience the sharing of a good feeling, create a positive metaphor or simile for someone you love, or maybe even a friend, and tell them, and you might be surprised by the reaction.
Information on metaphors by Robert J. Sternberg