Thanks for sending me exactly the kind of counterexample I need for my foundations book. It will do very nicely as an exercise in the section on factorisation systems. I shall have to think a bit more about the one involving presentations of categories which Art Stone and others mentioned. I am coming to Canada for LiCS in Montreal next month. My flight plan is to arrive in Toronto on Saturday 12 June and return from Montreal (via (!!) Toronto) after LiCS. I wonder whether the people at York would like to hear a seminar from me in return for some local accommodation for a few days? Several subjects are on offer: stable domain/category theory (see the papers in my ftp archive, which I think soem of you already have), intuitionistic ordinals, synthetic domain theory, as you please. Paul Taylor +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++