Probably the ur-text for Conceptual Metaphor.
Lakoff and Johnson, *Metaphors We Live By 
*, 1980. (I read the first edition; there is a second edition I haven't read.)
Some snippets of text or ideas:
* Argument Is War * Abstract Source Domains * Repeated Target Domains * Gestalt * Structured Experience * Metaphorically Structured Concepts * Front and Back * Joint Coherence * Interactional Properties are Key to Concepts * Metaphor Informs Form * Coping With Experience * Defining Experienced Reality * How Can a Statement Be True? * A Constant Shifting of Metaphors * Cafe Phenomenology * Limitations of Communication