On John M. Allegro’s Suggestion That the Tree of the Knowledge of Good and Evil in the 12th Century Plaincourault Chapel Depicts an Amanita muscaria Mushroom

In his book The Sacred Mushroom and the Cross (1970), John Marco Allegro claimed that an obscure, 12th century CE fresco of the Fall of Adam and Eve in the Plaincourault Chapel in Mérigny, France, provided evidence of the persistence in Christian Europe of an underground sacred mushroom sect that had survived since New Testament times. At the heart of Allegro’s claim is the mushroom-like appearance of the Tree of the Knowledge of Good and Evil in the picture. Following up on Allegro’s claim, a small group of writers, led by Boston University’s Carl A. P. Ruck, spent decades seeking to validate Allegro’s theory by seeking out other examples of psychedelic mushrooms hidden in early Christian and Medieval art. The present article centers its discussion on the claims put forward by Allegro and his followers about the Plaincourault tree, but also about other images concerning which they have made similar claims. It concludes that the claims of Allegro and his followers concerning the Plaincourault tree fail due to their tendency to overpress similarities while ignoring differences.