Barry R. Clarke is puzzle columnist for Prospect magazine (UK) and has written over 1000 mathematics and logic puzzles for The Daily Telegraph. He has a M.Sc. in theoretical physics with published papers in quantum mechanics, and an academic book 'The Quantum Puzzle: Critique of Quantum Theory and Electrodynamics' that sets out a new theory of the mass vortex ring. His PhD thesis was entitled 'A linguistic analysis of Francis Bacon's contribution to three Shakespeare plays' and it has led to published papers on 'The Tempest'. His book 'Challenging Logic Puzzles Mensa' is an amazon bestseller having sold over 80,000 copies (May 2017).