"The medieval mind couldn't conceive of the fact that classical form and classical subject matter belonged together," Erwin Panofsky, art historian of the Institute for Advanced Study in Princeton, told a capacity audience in the Fogg Large Lecture Room last night.

The subject of his talk was "Mithras in Monreale?" Mithras was a sun deity of Indian origin. But Panofsky said he was "not concerned with Mithras so much as the spirit of the Middle Ages."

Panofsky said that the statue of Mithras in the cloisters of Monreale has been cited as an example of a classical subject used in the twelfth century undisguised by medieval form.

Panofsky denied this, asserting that, "not 'til 1615 was Mithras' classical role really rediscovered. Even the Renaissance had no idea of the true signicance of those Roman reliefs which we have learned to understand as the representatives of the Persian Mithras," he said.

"The medieval beholder could appreciate the beauty of classical sculpture only if it was used in behalf of a medieval idea," he added.

Citing many funny examples, Panofsky explained his 'law of disjunction': "Whenever in the high or later Middle Ages a work of art borrows the form of a classical model, this form is always presented in a non-classical image." He discussed the Mithras statue as one of many "instances which have been introduced as refuting my good and cherished 'law of disjunction'."