The basic idea is this.
Some
aggregate subjects exists in virtue of several individuals
(self-)representing themselves as that aggregate subject.
-- long-term
Seems to depend on long-term collaboration, or at least the potential for it
‘A corporate attitude (of a collective) is an attitude held by the collective as an
intentional agent. To say that a collective holds a corporate belief or desire in
some proposition p is to say that the collective is an agent in its own right,
which holds that belief or desire. Thus not all collectives are capable of
holding corporate attitudes; only those that qualify as group agents are.
For example, the United States Supreme Court and other collegial courts arguably
fall into this category, as do commercial corporations, NGOs, and other purposive
organizations such as cohesive political parties, universities, and especially states.
In consequence, they are capable of holding corporate attitudes. By contrast, a random
collection of individuals, such as the people who happen to be on Times Square at a
particular time, does not. Such a collection cannot hold corporate attitudes.’
\citep[p.~1615]{list:2014_three}
-- depends on shared intention
What kind of attitudes must individuals have towards a group agent in
order to bring it into being? Typically they need a shared intention (which they may have
prior to constituting a group agent) to form a group.
‘we shall abstract from some differences between these approaches and adopt the
following stipulative approach, broadly inspired by Bratman (1999). We say that
a collection of individuals ‘jointly intend’ to promote a particular goal if
four conditions are met:
Shared goal. They each intend that they, the members of a more or less salient collection, together promote the given goal.
Individual contribution. They each intend to do their allotted part in a more or less salient plan for achieving that goal.
Interdependence. They each form these intentions at least partly because of believing that the others form such intentions too.
Common awareness. This is all a matter of common awareness, with each believing that the first three conditions are met,
each believing that others believe this, and so on.’
\citep[p.~33]{list_pettit:2011}
-- inferrential integration
The aggregate agent is something with a life of its own, which you may influence
but certainly do not control.
So *if* we said (and I don’t think Pettit does) that having a shared intention is a
matter of the aggregate agent having an intention, we would
fails the to meet the requirements on inferential and normative integration of shared intentions
with intentions.
This is not to say there aren’t such things as aggregate agents that result
from shared intentions or other attitudes towards the aggregate agent.
My point is just that these can hardly be foundational.
Note especially that this is no objection to List & Pettit given their aims; just qualifications
on what we can achieve by borrowing their ideas.
‘Since a joint action can be an isolated act performed jointly by several individuals,
it does not necessarily bring into existence a fully fledged group agent in our sense
... In particular, the performance of a single
joint action is too thin ... to warrant the ascription of a unified agential
status ... For example, in the case of fully fledged agents
... we can meaningfully hypothesize about how they would behave
under a broad range of variations in their desires or beliefs, whereas there is a severe limit
on how far we can do this with a casual collection that performs a joint action. Moreover, any
collection of people, and not just a group with an enduring identity over time, may perform a
joint action, for instance when the people in question carry a piano downstairs together or
spontaneously join to help a stranger in need. Thus mere collections may be capable of joint
agency, whereas only groups are capable of group agency in the stronger sense we have in mind.
However, joint actions, and the joint [shared] intentions underlying them, may play a role in the
formation of group agents’
\citep[n.~18, pp.~215-6]{list_pettit:2011}