The painting depicts a surgeon, wearing a funnel hat, removing the stone of madness from a patient's head by trepanation.

The inscription in gold-coloured Gothic script reads: (Middle Dutch): Meester snyt die keye ras Myne name Is lubbert Das

Lubbert Das was a comical (foolish) character in Dutch literature.

The woman balancing a book on her head is thought by Skemer to be a satire of the Flemish custom of wearing amulets made out of books and scripture, a pictogram for the word phylactery.

Michel Foucault, in his 1961 book History of Madness, says "Bosch's famous doctor is far more insane than the patient he is attempting to cure, and his false knowledge does nothing more than reveal the worst excesses of a madness immediately apparent to all but himself."