"Dmitry A. Kazakov" wrote in message news:u02hetbmsmkk$.18b13ph0ab35n.dlg@40tude.net... > On Tue, 30 May 2006 09:11:39 +0200, Jan Vorbr�ggen wrote: > > >> Ah, but an unforeseen error is a bug. One cannot be bug-tolerant, it is > >> self-contradictory, after all. Programming error (bug) means that the > >> system's state is not adequate to the physical system. Which could be the > >> rocket falling right onto the control tower. But that's no matter, because > >> there is no way for the program to know anything about that. Once you start > >> to judge about such undesired program states (even purely statistically), > >> and change the program, they automatically become *foreseen*. > > > > I don't consider that distinction helpful - it's like saying that economically > > important algorithms are NP-complete and thus unsolveable, while experience > > tells you that almost all practical problems turn out to be solveable with > > polynomial algorithms or at least reach approximations to the optimal solution > > that are economically indistinguishable. > > Good example. You cannot solve NP, but you can a practical [sub]problem. > Exactly so, you cannot write a bug-tolerant program, You can have a bug-tolerant program. > but you can a fault-tolerant one. And you can have a fault-tolerant one too.