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Togetherness vs the Simple Theory of Joint Action

The Simple Theory

Two or more agents perform an intentional joint action
exactly when there is an act-type, φ, such that
each agent intends that
they, these agents, φ together
and their intentions are appropriately related to their actions.

This will generate an objection. But, first, why do we need ‘together’ at all?
First simplify by switching to the simpler statement of the view ...
[Not covering it in this version because I no longer think the Schweikard and Schmid (2013) objection is good. They ask, ‘[H]ow can an individual refer to a joint activity without the jointness [...] already being in place?’ (Schweikard & Schmid, 2013). Obvious reply is that lots of intentions ultimately concern things that are not already in place (intention to poison does not require that the poison is already in place); so either reference is possible or else it is not necessary. (Of course this cannot be what Schweikard and Schmid have in mind; but their objection doesn’t seem very helpfully formulated.) ]
Recall that the Simple Theory is an answer to our question, What distinguishes joint action from parallel but merely individual action?

We each intend that we, you and I, cycle to school together.

Consider a first objection to the Simple Theory, a threat of circularity. You might imagine that appealing to togetherness in the specifying the content of the intention introduces circularity.
**Doesn’t doing something together involve exercising shared agency? And if it does, aren’t we explaining shared agency by appeal to intentions to exercise shared agency?**
To see how this objection arises, consider whether the ‘together’ is necessary. Here are two possible intentions:

Contrast:

We each intend that we, you and I, cycle to school together.

We each intend that we, you and I, cycle to school apart.

Suppose we each had and acted on the latter intention (that we, you and I, cycle to school apart). Then our actions would not be joint actions. So apparently, appealing to togetherness is essential.
But doesn’t invoking the togetherness of our this mean assuming the very thing we were supposed to be characterising---namely joint action?
Two ropes hanging over either side of a high wall are connected to a heavy block via a system of pulleys. Ayesha and Beatrice pull the ropes simultaneously, causing the heavy block to rise as a common effect of their actions. Each individually intends to raise the block. Each can see the block’s rise but, because of the high walls, neither of them is aware of the other, nor even that anything other than her own action is necessary for the block to rise.
In fact neither is aware that they are acting with another individual. Each believes, falsely, that there is a simple motor on the other end of the pulley, and that when the rope tenses the motor will turn.
Consider two questions ...

Are Ayesha and Beatrice
acting together?

Is Ayesha and Beatrice’s
lifting the block together
a joint action?

This question is less straightforward to answer than the first two. There actions are coordinated and have a common effect, but we saw earlier that this is true of many things which merely involve people acting in parallel rather than exercising shared agency.
I think most people working in this area would say that Ayesha and Beatrice’s lifting the block together is not a joint action. But in this area there is a real danger that we are just trading intuitions. So let’s see if we can find a basis for deciding whether this is a joint action.

collective vs distributive

Here are two sentences:

The tiny drops fell from the bottle.

- distributive

The tiny drops soaked Zach’s trousers.

- collective

The first sentence is naturally read *distributively*; that is, as specifying something that each drop did individually. Perhaps first drop one fell, then another fell.
But the second sentence is naturally read *collectively*. No one drop soaked Zach’s trousers; rather the soaking was something that the drops accomplised together.
If the sentence is true on this reading, the tiny drops' soaking Zach’s trousers is not a matter of each drop soaking Zach’s trousers.
[*Might need more examples. Bad pint? Ask them to think of an example?]
Here is a second example contrasting distributive vs collective interpretations. Consider the sentence ‘The ants carried tiny stones’. This is naturally interpreted as implying only that each ant carried a tiny stone, which is a distributive interpretation. By contrast, consider this ...
Some ants harvest plant hair and fungus in order to build traps to capture large insects; once captured, many worker ants sting the large insects, transport them and carve them up (Dejean, Solano, Ayroles, Corbara, & Orivel, 2005). There’s a lot you might extract from this behaviour (and we will return to the ants later), but for now just focus on the killing. Each ant stings the large insect they have captured, where none of the stings are individually fatal although together they are deadly. So when I tell you that the ants killed the large insect, this should be interpreted collectively. That is, it is not a matter of each ant killing the large insect; rather killing is collectively predicated of the ants.
You have two minutes to think of two sentences which, like mine, illustrate the contrast between collective and distributive.

Give another
collective-distributive
contrast pair.

Here are is my first example of the distinction between distributive and collective interpretations again ...

The tiny drops fell from the bottle.

- distributive

The tiny drops soaked Zach’s trousers.

- collective

Now consider an example involving actions and their outcomes:

Their thoughtless actions soaked Zach’s trousers. [causal]

- ambiguous (really!)

This sentence can be read in two ways, distributively or collectively. We can imagine that we are talking about a sequence of actions done over a period of time, each of which soaked Zach’s trousers. In this case the outcome, soaking Zach’s trousers, is an outcome of each action.
Alternatively we can imagine several actions which have this outcome collectively---as in our illustration where Ayesha holds a glass while Beatrice pours. In this case the outcome, soaking Zach’s trousers, is not necessarily an outcome of any of the individual actions but it is an outcome of all of them taken together. That is, it is a collective outcome.
(Here I'm ignoring complications associated with the possibility that some of the actions collectively soaked Zach’s trousers while others did so distributively.)
Note that there is a genuine ambiguity here. To see this, ask yourself how many times Zach’s trousers were soaked. On the distributive reading they were soaked at least as many times as there are actions. On the collective reading they were not necessarily soaked more than once. (On the distributive reading there are several outcomes of the same type and each action has a different token outcome of this type; on the collective reading there is a single token outcome which is the outcome of two or more actions.)

Claim:

When collective, they act together.

Compare these three sentences ...

The tiny drops soaked Zach’s trousers together.

The three legs of the tripod support the camera together.

Ayesha and Beatrice lifted the block together.

I want to suggest that reflection on these allows us to distinguish merely acting together from performing a joint action. Why? ...
  1. In each case there is a collective interpretation.
  2. The collective interpretation is what makes ‘together’ appropriate.
  3. It is the same sense of ‘together’ in each case.
  4. The truth of the collective interpretation of (c) does not depend on there being any intentional joint action.
  5. (Ayesha and Beatrice need have no awareness of each other’s existence or actions; nor need they have intentions concerning anyone else.)
  6. So two or more people can do something together without thereby performing a joint action

We each intend that we, you and I, cycle to school together.