In considering joint action from a philosophical point of view
we face a counterpart to the The Problem of Action:
What distinguishes doing something jointly with another person from acting in parallel with
them but merely side by side?  (I’ll call this The Problem of Joint Action)
Here is a recent, more careful formulation of the Problem:
‘When we act together [...] we are not each simply acting in light of expectations of the
actions of others while knowing that those actions of others depend on their expectations
of our actions.
[...] merely publicly walking alongside
each other on a crowded sidewalk
without colliding, while involving complex forms of mutual responsiveness, is not yet walking
together in a shared intentional way.
Can we articulate conditions that go beyond such strategic
interaction and are sufficient for and illuminating of our acting together?’
(Bratman, 2014, pp. 1--2)
Why?
Philosophers’ ultimate aims are to ‘discover the nature of social groups in general’ (Gilbert, 1990, p. 2) and to understand the conceptual, metaphysical and normative aspects of basic forms of sociality (Bratman, 2014, p. 3).
But one route to these lofty goals is to focus on
solving The Problem of Joint Action—that is, on
distinguishing genuinely joint from merely parallel activities
in mundane cases involving two or three people.
Aim
After this section, you should understand what The Problem of Joint Action is.
But is it really a problem?
 
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