To anyone looking at it from the fondamenta (the canalside walkway), Palazzo Lezze seems just a long baroque Istrian-stone facade overlooking the rio (a small canal). But on the wall that faces the little campo of the Scuola Nuova the palace hides a riddle: set into the masonry, around and above the arched portal, are carved marble medallions — the patere — which have earned this house the nickname ’the philosopher’s house’.