Not sure

As you walk into the beautiful high Gothic cathedral in Sens (where Thomas à Becket took refuge in the 1160s) you can't miss this little head, gazing across the nave. Visitors always argue about it, and were at it again on my visit today. One legend says it was a cheeky signature by a worker. Another says that the master builder was reviled and this is how the workers expressed their loathing. A third says he was Jean du Cognot, a lawyer who ranted against the privileges of the Church, and was thus ridiculed.