# Mathematical object

A mathematical thing is an abstract concept arising in mathematics. In a usual language of mathematics, an object is anything that has been or could be formally defined, and with which one may make-up deductive reasoning as well as mathematical proofs. Typically, the mathematical thing can be a good that can be assigned to a variable, and therefore can be involved in formulas. usually encountered mathematical objects increase numbers, sets, functions, expressions, geometric objects, transformations of other mathematical objects, and spaces. Mathematical objects can be very complex; for example, theorems, proofs, and even theories are considered as mathematical objects in proof theory.