A telegraphic preview ...
If you ask scientists about action, they will tell you a story about motor representations
and processes.
And if you ask philosophers, they will tell you a story about intentions and practical reasoning.
Both stories seem reasonably compelling, and there is even evidence for one of them.
The stories have different strengths:
In cognitive science ... little to say about actions whose purposes
involve things the motor system doesn’t care about---your motor system
doesn’t care whether the plane you are stepping is headed for Milan or
for Rome, but this sort of difference can affect whether your actions succeed or fail.
You might just say that the two disciplines are talking past each other,
or you might say that they are offering two complementary but independent
models of action.
Call this the ‘Two Stories View’ (or divorced, but living together).
[Alt: quick version --- Ask a phil about action and they'll tell you a story about
intentions and processes of practical reasoning. Ask a psych ...
Do we need to connect these largely separate stories or is it
fine for each discipline to tell its own story about action? Let's see ...]
How are the two stories related?
One possibility is that they are two ways of talking about a single thing.
But this doesn't seem right because the stories explain different, if overlapping, phenomena.
The philosophers are interested in everything from extremely large scale actions which may take
days, like the action of competing in the Tour de France to very small scale actions such as the
action of turning a crank.
The psychologists, by contrast, are mostly interested in the small and very small scale actions.
So there is some overlap in actions like turning a crank, breaking an egg, taking and eating a
biscuit.
How are the two stories related if they are not using different words for the same thing?
Another possibility is that they are just completely unconnected. One is about the ‘space of reasons’,
another about the space of something else.
But this possibility is hard to square with the idea that intentions are causal elements in
processes which, often enough, result in the body moving.
It seems that the practical reasoning has to influence the motor processes, and perhaps conversely
too.
As Elisabeth suggested in a ground-breaking ‘dynamic theory of intentions’
(Pacherie, 2008, p. 181ff.), it is plausible that motor representations can
inherit goals from, and be influenced by, intentions (pp.~186--7).
Just here we face a practical problem. Because of the separation of concerns,
there very little research on how the two stories---the one about intentions and practical reasoning,
and the one about motor representations and processes---might join up.
So it is that the interface problem falls into the gap between philosophers’ concerns with practical
reasoning and scientists’ concerns with motor control.
But I'm getting ahead of myself.
‘Now what is an action? Not one thing, but a series of two things: the state of mind called a volition, followed by an effect. The volition or intention to produce the effect, is one thing; the effect produced in consequence of the intention, is another thing; the two together constitute the action.’
Mill, System of Logic (1.3.6) quoted in Hyman (2015, p. 218)
Intention to produce the effect
Speech actions also complex ...
And those component actions are instrumental ...
Each phonetic gesture involves a complex, coordinated movement of
lips, larynx, tounge and velum that is sensitive to context.
Jusczyk (1997, p. 44)
Why care about very small scale instrumental actions?
What is the relation between an instrumental action and the outcome or outcomes to which it is directed?
What is the relation between an instrumental action and the outcome or outcomes to which it is directed?
The same question arises for very small scale actions.
To illustrate ... on the left you see an actor pushing a ball;
on the right you see an actor part way through grapsing a ball.
But what makes it true that these actions are directed to those outcomes?
You might say: well it's just a matter of what the outcomes are.
But of course you can be attempting to grasp something and accidentally
end up pushing it (and conversely).