Greeted by my favourite unicorn, that is, back to Merton College. This 15th-century sculpture over the gatehouse has fascinated me since I joined Merton, eons ago, as a Junior Research Fellow. It is full of religious symbolism, some of it is completely lost on me. On the right is St. John the Baptist, carrying a book, the harbinger of Christ. The life of Christ is variously represented: his incarnation and exaltation (the unicorn); his sacrifice (the Lamb of God); his Resurrection (the lion); the Holy Spirit (the dove). Prominently displayed in the centre is the Book of Seven Seals, described in the Book of Revelation and symbolic of the Day of Judgement. The seven trees in the background have been identified (from the left) as the pomegranate (symbol of eternal life) or apple (tree of knowledge); the orange (fecundity); the ash (tree of the universe), box or hornbeam; the oak (fidelity); the beech (tree of nuts signifying the church) or sallow (medieval substitute for palm); the walnut (its shell standing for Christ’s human flesh covering his divine nature) or myrtle; the poplar (humanity). Attendant upon these mysteries is the kneeling figure of the founder - Walter de Merton wearing his bishop’s mitre.