Mathematics (from Greek μάθημα máthēma, "knowledge, study, learning") is the study of such topics as quantity, structure, space, and change. It has no generally accepted definition.
Mathematics is a versatile art; it can be applied to widely different purposes. Math has no morality; it does not care what it counts or what it proves.
Brian Stableford, Ashes and Tombstones, in Peter Crowther (ed.) Moon Shots (1999), reprinted in David G. Hartwell (ed.) Year's Best SF 5 (2000), p. 412
The quality and the quantity of fresh water resources face increasing challenges in many parts of Europe. Climate change, rapid population growth and urbanistion, diminishing freshwater resources, and ageing infrastructure are all taking their toll on our water supply.
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