[cap-talk] Is "Authority" Subjective?

[Mark Miller]

I'm only recently back in town and this is a long thread that I
haven't yet absorbed. I will try simply responding directly to the
original message mostly without the later context, as I think my reply
might take us in a different direction.


On 6/22/07, Toby Murray <toby.murray at comlab.ox.ac.uk> wrote:
> Hi cap-talk,
>
> I've hit an interesting issue during my work on the formal
> characterisation of authority. I've come to wonder whether the
> definition of "authority" is actually a bit subjective and
> intuition-dependent. I'm hoping this list can confirm or falsify this
> hypothesis.
>
> Suppose we have a system represented as the following CSP process (don't
> worry if you don't know CSP, I'll explain what's going on)
>
> P = a1 -> a2 -> b -> STOP []
>     b -> STOP
>
> Initially the system can perform either of the actions a1 or b. If it
> performs an a1, the only choice for the following action is a2, after
> which the only thing it can do is perform b. In both cases, after
> performing b, the system halts.
>
> 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?

I am among those who don't know CSP. However, your explanation seems
quite clear, thanks. But it does leave open a remaining crucial
ambiguity: Does the expression "b -> ...", combined with your
description "b is performed by another object Bob" mean 1) "If the
system is in a state where only b would be accepted and if Bob does
attempt b, then b will happen and cause the described state
transition." or 2) "If the system is in a state where only b would be
accepted, then Bob will perform b and cause the described state
transition."?

Interpretation #1 is more consistent with my vague sense of what CSP
is about. But this interpretation presumes to describe the actual
behavior of all the players, rendering the players too deterministic
to be considered players of a game, rendering any description of
authority mostly meaningless. As David Wagner says later on, causality
is about counterfactuals. A full characterization of everyone's
behavior leaves open where to draw the counterfactuals.

Interpretation #2 in effect says only what the bounds are on what the
players might do in a given state, without prescribing which of these,
if any, they will do. This interpretation is more consistent with your
arguments below, and with my sense of what authority analysis should
be about. Given this interpretation, I think your argument #2 is more
correct but misphrased. Alice can cause Bob not to be able to perform
b, therefore Alice can cause Bob to be able to perform b. But only if
we know that Bob will always attempt to perform b when it would be
accepted (as in interpretation #1), can we say that Alice can cause
Bob to perform b.

It seems that your arguments as stated require interpretation #2
regarding Alice's actions but interpretation #1 regarding Bob's. This
is consistent with the kind of authority analysis done by SCOLL, where
Alice would be described as a non-relied-upon subject and Bob would be
described as a relied upon subject.


> I can't decide -- I keep dithering between the following two arguments.
> I suspect that in different circumstances, both are valid. But I might
> be wrong -- I'm hoping you can help me decide whether one of them is
> definitely more valid than the other.
>
> Argument 1: Before Alice acts, Bob can perform b -- the system won't
> refuse it.

The above sentence suggests interpretation #1, where Bob might not
perform b even when he could.

> After Alice finishes acting, Bob can perform b -- the system
> won't refuse it.

But in you next argument, you imply that Alice might perform a1 and
not perform a2, which means Alice might have the authority to prevent
Bob from being able to perform b.

> With and without Alice acting, Bob can still perform b.

But if Bob might not actually perform b even when he could, then Alice
can't cause him to perform b, and so Alice doesn't have authority to
cause Bob to perform b.

> Hence, Alice doesn't cause Bob to perform b and hence, has no authority
> to do so.
>
> Argument 2: If Alice performs a1, she can cause Bob to perform b by
> performing a2. In fact, if she refuses to perform a2, the system
> deadlocks and Bob will never perform b.

If Alice can so refuse in a system described by this CSP expression
(as in interpretation #2), then Bob can likewise refuse to perform b.

> Hence, by performing a2, Alice
> causes Bob to perform b. Hence, Alice does have authority to cause Bob
> to perform b.

-- 
Text by me above is hereby placed in the public domain

    Cheers,
    --MarkM