George Lakoff and Mark Johnson's "Metaphors We Live By" explores the concept and function of metaphors in language. Whether we are aware of it or not, they say, metaphors play a role in the construction of realities through our conceptual system. While these metaphors are largely unconsciously recognized, they guide our understanding of experiences and influence what we do in every day life. In this way, metaphors can be perceived as the Agency through which users of language (Agents) develop and communicate an understanding of the world around them--based on the cultural context in which they live.
As an extension, metaphors act as Agency for cultures at large, allowing them to develop cultural-specific norms in language that are guided by their leading ideology, or episteme. We live in a society guided by a capitalist ideology, where acquiring money is of central focus and tools or materials that assist us in acquiring money are of utmost importance. Time is "precisely quantified", we are paid "by the hour, week, or year". Therefore, time is perceived as a limited resource, a valuable commodity. The metaphor "time is money" is an example of Western society's cultural principles manifested in language.
Both are highly regarded resources with close relations to each other in terms of value. Such a metaphor would not hold the same meaning in, say, a Latin American country where time is not valued in the same way as it is here. Metaphorical concepts such as this are systematically analyzed in this reading and various contextual interpretations are explored. Because words and phrases are unstable, that is, they cannot signify one singular idea only and entirely, the context in which a metaphor is used determines the way in which it is interpreted. "Time is money" means that time is both a limited resource and a valuable commodity. Time is money is the metaphorical concept, comprised of subcategories of meaning. The particular meaning being signified by the metaphor depends on what it is referring to. "[S]ome refer specifically to money (spend, invest, budget, probably cost), others to limited resources (use, use up, have enough of, run out of), and still others to valuable commodities (have, give, lose, thank you for)". The context-specific determination of meaning is consistent with Derrida's concept "differance"--the meaning of a word exists in an interrelated network or web of meanings; a word's meaning depends on its relationship to and distinction from other words in time and space.