n. pl. phi·los·o·phies
1. The study of the nature, causes, or principles of reality, knowledge, or values, based on logical reasoning.
2. A system of thought based on or involving such study: the philosophy of Hume.
3. The study of the theoretical underpinnings of a particular field or discipline: the philosophy of history.
4. An underlying theory or set of ideas relating to a particular field of activity or to life as a whole: an original philosophy of advertising; an unusual philosophy of life.
[Middle English philosophie, from Old French, from Latin philosophia, from Greek philosophiā, from philosophos, lover of wisdom, philosopher; see PHILOSOPHER.]
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