Cistercian numerals, also known as "Monk's numerals" or "Cistercian monks' numerals," are a unique and historical numeral system developed and used by the Cistercian monks during the Middle Ages. Unlike the commonly used Arabic or Roman numerals, Cistercian numerals consist of a set of simple geometric shapes arranged in specific patterns to represent different digits.
The system comprises four basic symbols, each representing numbers from 1 to 9. By combining these symbols in various configurations, the Cistercian monks could express larger numbers with ease. The numerals are read from left to right, and each shape contributes its respective value to the total.
Cistercian numerals were primarily used for manuscript notations and accounting purposes within the monastic communities during the medieval period. Today, they serve as an intriguing historical curiosity and offer insights into the mathematical practices of the time. While no longer in widespread use, they remain a fascinating aspect of medieval numeral systems.