quantity

In mathematics, a quantity refers to an amount or number that can be measured or estimated. It is a fundamental concept that describes the aspect of a thing in terms of its magnitude, whether greater, less, or equal. This can be an indefinite amount or a specific, calculated value.1

The concept of numbers has evolved significantly over time. Initially, mathematicians debated the legitimacy of various types of numbers, such as irrational, negative, and complex numbers. However, these discussions eventually subsided, leading to a new phase of systematization and the search for adequate foundations for different number systems.2