Noun
That science, or class of sciences, which treats of the exact relations existing between quantities or magnitudes, and of the methods by which, in accordance with these relations, quantities sought are deducible from other quantities known or supposed; the science of spatial and quantitative relations.
Source: Webster's dictionaryTo those who ask what the infinitely small quantity in mathematics is, we answer that it is actually zero. Hence there are not so many mysteries hidden in this concept as they are usually believed to be. Leonhard Euler
The mathematics is not there till we put it there. Arthur Eddington
Mathematics is the art of giving the same name to different things. Henri Poincaré
God used beautiful mathematics in creating the world. Paul Dirac
In mathematics you don't understand things. You just get used to them. John von Neumann
Mathematics is the only science where one never knows what one is talking about nor whether what is said is true. Bertrand Russell