Wombat said:Atlas put out two great supplements regarding Jewish mysticism (Kaballah) and Islamic magics (Blood & Sand).
Knowing the author of the second, I have seen early work by him to convert his 4th ed material over to the 5th ed rules, which will mainly take work in the Virtues/Flaws department. It's good material and he has extra (and I think better stuff) over at his website.
In this case we're getting into art as a form of expression, as a representation of the world or an aspect of the world. In which case Hermetic magic and Jewish and Moslem mysticism would be considered different techniques. Much as oil and acrylics use different techniques to create a painting.
I must now ask, where does one find your friend's website?
And a heads up for fans of ArM: GURPS: Magic is scheduled to be out soon. GURPS Fantasy is now shipping, and last I heard G:M was at the printers. While written for GURPS they are eminently usable with most any fantasy RPG out there.