Cistercian numeral system - photo

[mklotz]

I think the most interesting question is, "Why do a gaggle of monks need a more compact number representation?".

Parchment isn't so expensive that saving a tiny fraction of its area is important. Besides, scripture doesn't include a lot of computations or equations.

Two thoughts here...

It's really a code to conceal some illicit operation in which the monks are involved.

It's based on their warped idea of righteousness. Arabic numerals originated in a non-christian area and so are sinful. These are proper religious digits.