It's interesting, because it relates the magician with the madman. There are several paintings of this time that speak of the "stone of madness." I dont know if, indeed, conducting operations in the head (trepanation), but Hyeronimus Bosch is one of the activities attributed to the "magician" (the deceiver, Chapman).
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Es interesante, porque relaciona el mago con el loco. Hay varias pinturas de la época que hablan de la "piedra de la locura". No sé si, de verdad, realizaban operaciones en la cabeza (trepanaciones), pero el Bosco es una de las actividades que atribuye a the "magician" (el estafador, el que engaña, el buhonero).

pretty words...