For over half a century, starting around 1960, physics education was put under the intellectual
microscope of a London-based university lecturer — Dr John Warren. His scrutiny of physics textbooks
and examination papers in particular led him to conduct a sustained assault on error, ambiguity and
lack of rigour in the presentation of our subject. This biographical article attempts to convey
something of the nature of the man and his mission, and perhaps to sow the seeds of the reform for
which he strove.