Nichols, Aidan Op: - Aidan Nichols, OP (PhD, University of Edinburgh), of Blackfriars, Cambridge, is a lecturer at the University of Cambridge. He previously served as John Paul II Memorial Visiting Lecturer at the University of Oxford and as a Fellow of Greyfriars, Oxford. He is one of the most prolific writers of theology in the English language and is the leading authority on the theology of Hans Urs von Balthasar.