The toad in European magic: poison, stone and the witches of Navarre

Among the animals that European tradition linked to magic, the toad holds a peculiar place. Repulsive in the eyes of many, it was considered venomous and unclean, and yet it was believed to keep a precious gem inside its head. This double nature, together with its secluded life among mud, stones and damp cellars, made it a constant presence in descriptions of sorcery, in treatises on natural history and, later, in drama and literature.

The ancient sources

As early as the first century, Pliny the Elder devotes ample space in his Natural History to frogs and toads, singling out a species he calls rubeta, the bramble frog. He speaks of it as an animal full of poison and records the many extraordinary virtues that magicians attributed to it, while showing a certain scepticism towards these claims. The text matters because it fixed for centuries the idea of the toad as a favourite material of magicians.

The poison was not entirely imaginary. Many European toads, such as the common toad, secrete irritating substances from glands in their skin that protect them from predators. The observation of this phenomenon, magnified by fear, fed the conviction that the animal could poison by mere contact or even by its gaze, an idea without foundation but remarkably persistent.

The stone in the head

In the Middle Ages and the Renaissance a belief spread in the bufonite, or toadstone, which the animal was supposed to carry in its head. Lapidaries and treatises credited it with the power to reveal poisons by changing colour. In reality the objects sold as toadstones were mostly fossil teeth of an extinct fish, Lepidotes, rounded and glossy in shape.

Shakespeare takes up the belief in As You Like It, where the exiled duke observes that the toad, «ugly and venomous», nevertheless wears a precious jewel in its head. The image becomes a small moral lesson: even the most unpleasant adversity can give rise to something valuable. Toadstones were set in rings and pendants that are kept today in several European museums.

Toads and witches

In the witch trials the toad often appears as a companion of the accused. The most famous case is that of Zugarramurdi in Navarre, judged by the Inquisition at Logroño in 1610: the confessions gathered there spoke of toads dressed in little garments and entrusted to the care of the witches. It was precisely after this trial that the inquisitor Alonso de Salazar Frías expressed strong doubts about the reality of what had been confessed.

English literature records the same association. In Macbeth the three witches throw a toad into the cauldron among the ingredients of their charm, and the scene helped fix the link between the animal and black magic in the modern imagination. Rather than describing real practices, the play draws on stereotypes already widespread in the demonological literature of its time.

The toad sums up well how premodern culture read nature. An animal harmless to anyone who does not handle it was charged with immense powers, for evil as for good. Poison and gem, repugnance and worth coexist in its figure, reminding us that symbols often arise from a partial observation of a real fact, transformed by the collective imagination.