This book provides a comprehensive philosophical theory explicating the cognitive contribution of metaphor. Metaphor effects a transference of meaning, not between two terms, but between two structured domains of content, or 'semantic fields'. Semantic fields, construed as necessary to a theory of word-meaning, provide the contrastive and affinitive relations that govern a term's literal use. In a metaphoric use, these relations are projected into a second domain which is thereby reordered with significant cognitive effects. The book is a detailed revision and refinement of 'the semantic theory of metaphor'. Taking into account pragmatic considerations and recent linguistic and psychological studies, the author forges a new understanding of the relation between metaphoric and literal meaning. She amply illustrates her thesis with sensitive and systematic analyses of metaphors found in literature, philosophy, science, and everyday language.