**Arithmetic** or arithmetics (from the Greek word = number) is the oldest and most elementary branch of mathematics, used by almost everyone, for tasks ranging from simple day-to-day counting to advanced science and business calculations. It involves the study of quantity, especially as the result of combining numbers. In common usage, it refers to the simpler properties when using the traditional operations of addition, subtraction, multiplication and division with smaller values of numbers. (Wikipedia)

"Proportion belongs to geometry and harmony, measurement to the object and to **arithmetic**; and one necessitates the other. Proportion is the comparison of sizes; harmony is the relationship to measures; geometry is the function of numbers." [R. A. Schwaller de Lubicz, The Temple in Man, page 61]

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See Also

**Add**
**Addition**
**Division**
**Chord**
**Divide**
**Equals**
**Factoring**
**Geometry**
**Interval**
**law of multiple proportions**
**law of constant composition**
**Law of Definite Proportions**
**Mathematics**
**Minus**
**Multiplication**
**Music**
**Number**
**Proportion**
**Propositions of Geometry**
**Quantum Arithmetic**
**Ratio**
**Stoichiometry**
**Subtraction**
**Sympsionics**
**Times**