[cap-talk] Capabilities giving up control?

[Jed Donnelley]

At 10:53 PM 1/29/2008, Toby Murray wrote:
>On Fri, 2008-01-25 at 08:02 -0800, Norman Hardy wrote:
> > On 2008 Jan 20, at 5:02 AM, John McCabe-Dansted wrote:
> >
> > > "Authority" seems to be very close to the common English meanings of
> > > Influence, Power and Ability.
> > >   See e.g. http://en.wikipedia.org/wiki/Influence
> > >
> > > However I'd like to clarify one possible exception. We may casually
> > > say that X can "influence" Y via a covert channel, but Y might not
> > > be in the transitive closure of permissions. Or would we say that X
> > > and Y have permissions to the shared resource used to implement the
> > > covert channel?
> >
> > We have been vague about the meaning of "transitive closure" I think.
> > Ordinary usage of 'authority' might say that I don't have the
> > authority to stop you from flying just because I am in a position to
> > buy the last available ticket.
>
>I'd disagree.  This is simply about causation. I can cause you to be
>unable to fly by purchasing the last remaining ticket before you do.

So in our technical sense being in the position to buy the
last ticket does grant one the "authority" to stop others
from flying.  However, I think Norm's point was that this
isn't ordinary (common, every day, social English) usage.
I don't believe most people would say that being able to
buy the last ticket confers an 'authority' to stop people
from flying.  I believe in that part of his post he was
just contrasting common usage with the technical usage
that we've adopted on this list - causation as you say.

My interpretation of his words - always a chance to get
into trouble, but also perhaps a chance to clarify
commonly understood usage.

--Jed  http://www.webstart.com/jed-signature.html