Collected works of A. M. Turing. Volume 4: Mathematical Logic

Although the unpublished papers were left to Robin Gandy in Turing's will, the matter of inquiring into the possibility of their publication seems to have rested in the first instance with Max Newman1. Newman ran into problems with the assessment of some of the unpublished papers, and then on retiring in 1963 he left the whole matter in Robin's hands. It was in fact far too big a task for one person but that was not truly realised until 1988 when Professor Furbank, Turing's executor and overall editor of the Collected Works, stepped in to take a new initiative. There followed an intensive period of activity in which he brought in three additional editors. They did a remarkable job and their volumes were published in 1992. So why has this, the fourth volume, taken so much longer? As often there is no single reason, but some explanation is due...