[cap-talk] Capabilities giving up control?

[Toby Murray]

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.