Re: Does an agent have "live" on a world???

[glen e. p. ropella]

Sven N. Thommesen writes:
 > The question of agent "existence" is a multi-faceted one! There are several
 > 'levels' of existence in a Swarm simulation:

Let me see if I can shorten this up:

Existence:
   0) existence in process space (particularly the data segment)
   1) existence in message space (ObjC messages can be sent to it)
   2) existence in event space (it can affect the sim)
      - there's two levels of event space in Swarm, process events and Actions

Affective Visibility:
   3) which objects can see it, directly or indirectly
      5) externally initiated messages to the object

Effective Visibility:
   4) which objects an object must see in order to act
      6) internally motivated messages to other objects

 > In the case of a sim holding lists of 'pre-birth' and 'post-death' agents,
 > these agents will exist in the senses (0) and (1), but they will only
 > "exist" in sense (2) when they are part of some list which is 'visible' to
 > other agents and the Action machinery.

I think it's safe to say that the truth of (2) for an agent implies
the situations described by (3) or (4).  I.e. (3) or (4) are necessary
for (2).

Whether or not (3) or (4) or (3) and (4) are sufficient for (2) is
another question.  And I'm pretty sure the answer is "no."  I think
the further requirement of (6) would be sufficient to ensure (2),
though.  It's questionable as to whether or not the truth of (5)
is sufficient for (2), because a method in an agent can be a null
op.  Does that null op actually "affect the sim"?  It certainly 
does at some level.... but, maybe not at a high enough level for
anyone to care.

 > And forgive me if this got too didactic -- I get this urge sometimes to
 > cross the t's and dot the i's ...

Didactic?!?  Quit yer usin' dem big words!  Just 'cause you's gettin'
your doctorate of filahsofy don't mean you can come back 'round treatin'
us like dirt, now, ya hear?  [grin]

glen
-- 
{glen e. p. ropella <address@hidden> |  Send lawyers, guns, and money!  }
{Hive Drone, SFI Swarm Project         |            Hail Eris!            }
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