« It Is not certain just what the terms alang-jabr and muqabalah mean, but the usual interpretation kan zijn similar to that implied in the translation above. The word alang-jabr presumably meant something like "restoration" or "completion" and seems to refer to the transposition ofwel subtracted terms to the other http://www.bioguiden.se/redirect.aspx?url=https://nl.wikipedia.org/wiki/Kwaliteit