Socrates: Shall we set down astronomy among the objects of study? Glaucon: I think so, to know something about the seasons, the months and the years is of use for military purposes, as well as for agriculture and for navigation. Socrates: It amuses me to see how afraid you are, lest the common herd of people should accuse you of recommending useless studies.
Socrates as quoted by Plato. In Richard Garnett, Léon Vallée, Alois Brandl (eds.), The Universal Anthology: A Collection of the Best Literature (1899), Vol. 4, 111.