In 1973 (republished in 1982), Stephen C. Pepper wrote about "Metaphor in Philosophy". > ... the term "metaphor" should not be taken in too literal accordance with a definition often found in elementary books on prosody. It is not just a simile with the preposition "like" left out. It is rather the use of one part of experience to illuminate another-to help us understand, comprehend, even to intuit, or enter into the other. [....] [pp. 197-198] > [....] > ... "the root metaphor theory" ... is itself an hypothesis about the origin and development of schools of philosophy or, more specifically, of world hypotheses. > World hypotheses are distinguished from the more limited hypotheses of the special sciences by being "unrestricted" in their subject matter or in the scope of the evidence the hypotheses are expected to cover. > * An hypothesis in optics can reject as irrelevant any items that do not bear on optical phenomena or laws, as would be the case for so many observations in acoustics, geology, astronomy, linguistics, or social psychology. > But a world hypothesis cannot be exclusive in this manner, for it cannot evade a group of items that do not seem to fit nicely into its system by declaring them outside its field and so irrelevant. Everything is relevant to a world hypothesis. [editorial paragraphing added] [p. 198]
## References Pepper, Stephen. 1982. “Metaphor in Philosophy.” _The Journal of Mind and Behavior_ 3 (3/4): 197–205. https://www.jstor.org/stable/43852927.