How to get rid of unwanted fuzz

Antony Galton

(University of Exeter)

Zeno's runner, Thompson's lamp, Littlewood's whip: anyone who sets about trying to systematize the principles of temporal reasoning sooner or later comes face to face with the problem of what to do about the possibility of a proposition's changing its truth-value infinitely often in a finite period of time. This phenomenon is called "fuzz" by Prior, "intermingling" by Hamblin, "clustered variation" by Davis. Should we allow it to happen, and if not, how can we prevent it? I shall take a look at the history of attempts to rule out phenomena of this kind by means of axioms in a temporal logic: and show that most of them fail to do exactly what was intended.
Tuesday 31st January 1995, 14:30
Seminar Room 322
Department of Computer Science