The grade structure of the Golden Dawn supposedly allows for a grade entitled Ipsissimus, also known by the enumeration 10=1, which corresponds to the Qabalistic Sephirah of Kether. However much controversy surrounds this and other higher grades of the Golden Dawn system. The controversy mainly concerns whether the grade in fact exists for ordinary humans, and if it does, whether it actually means anything or not.
Chic and Sandra Tabatha Cicero have stated simply that the grade cannot be attained by living adepts. However, there is at least one modern GD order which claims that is has the authentic rituals and teachings of the grades of Magister Templi, Magus and Ipsissimus.