Definitions of Metaphor
The broadest of the tropes, a metaphor is a substitution of any dissimilar terms. It corresponds to the topos of Similarity / Dissimilarity. It is often used in place of "trope".
Simile
For our purposes, a simile is a metaphor with the comparison spelled out—the function otherwise is parallel.
"An implied comparison between two things of unlike nature that yet have something in common." [1].
Notes on Metaphor
Metaphor has been treated as a way of organizing the world since Vico first applied it to a theory of history. It is one of Kenneth Burke's "Four Master Tropes." [2] Northrop Frye (396) [3] followed Vico [4] in his discussion of the metaphorical world view, which he distinguished from the Metonymic and Descriptive world views.
Stephen Pepper [5] introduced the concept of a "root metaphor" in his work World Hypotheses, which also follows Vico in proposing a limited number of ways of organizing the world, each around a basic functional assumption about the nature of structure in the form of a root metaphor.
Examples of Metaphor and Simile
Please contribute current, striking, and enlightening examples of metaphor in public discourse here.
"My love is like a red red rose" from Robert Burns.
"I assume unhesitatingly the leadership of this great army of our people dedicated to a disciplined attack upon our common problems." -Franklin D. Roosevelt, First Inaugural Address
"You walk in and you can kind of envision your life there. It's like a first date. You know in the first 30 seconds." -Katie Couric on house hunting [6].
“America has tossed its cap over the wall of space!”- John F. Kennedy‘s Remarks at the Dedication of the Aerospace Medical Health Center (San Antonio, TX, November 21, 1963)