[cap-talk] Is "Authority" Subjective?

[Pierre THIERRY]

Scribit Toby Murray dies 22/06/2007 hora 12:23:
> Now suppose that actions a1 and a2 are performed by some object Alice
> and b is performed by another object Bob. Does Alice have authority to
> cause Bob to perform b?

The problem is maybe the definition of authority. As I have understood
it from various discussions and presentations about capabilities, here
we mean that a subject A has a permission on object B if A can invoke
some methods of B, and that A has an authority on B if A can use some of
its permissions for some methods of B to be invoked.

So authority seems entirely objective to me. Probably undecidable in the
general case, but not subjective.

> Argument 1: Before Alice acts, Bob can perform b -- the system won't
> refuse it. After Alice finishes acting, Bob can perform b -- the
> system won't refuse it. With and without Alice acting, Bob can still
> perform b.  Hence, Alice doesn't cause Bob to perform b and hence, has
> no authority to do so. 

I'm not sure that stands. Wether Bob may decide to do b indepently of
the request of Alice is orthogonal to wether Bob will do b if Alice
requests it.

If Bob is coded to serve each request of Alice to do b, then Alice has
the authority to do b.

Curiously,
Pierre
-- 
nowhere.man at levallois.eu.org
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