[cap-talk] Is "Authority" Subjective?

[Jonathan S. Shapiro]

On Sun, 2007-06-24 at 21:29 +0100, David Hopwood wrote:
> David Wagner wrote:
> > Toby Murray writes:
> >> Suppose we have a system represented as the following CSP process:
> >>
> >> P = a1 -> a2 -> b -> STOP [] 
> >>     b -> STOP
> >
> > If yes, my concern with this framework is that the non-determinism
> > in the CSP process P conflates several different kinds of choices or
> > several different sources of non-determinism:
> 
> In CSP as conventionally interpreted, P has no nondeterminism. It is
> a process with deterministic behaviour depending on the environment it
> is placed in. There is a separate operator ⊓ (U+2293 SQUARE CAP), that
> introduces nondeterminism and is quite different from [] (choice).
> It sounds as though Toby may be using a different interpretation,
> but I don't understand precisely what the difference is.

Thank you. Indeed the operation I was after was "choice". In the usual
models we do not know the code obeyed by the program, so we assume that
the program *may* perform any operation that it *can* perform.

But you are indeed correct that the operation I wanted was "choose".