So I was trying to figure out what agency is. Let’s try the usual starting point first:
What does it mean “to act in a world”? Wikipedia, again:
Basic action theory typically describes action as behavior caused by an agent in a particular situation.
…And we are back to “what is agency?” (and what is behavior).
OK, let’s try SEP:
Donald Davidson [1980, essay 3] asserted that an action, in some basic sense, is something an agent does that was ‘intentional under some description,’ and many other philosophers have agreed with him that there is a conceptual tie between genuine action, on the one hand, and intention, on the other.
…So action is, again, something that an agent does. (SEP does not have a separate entry for agency.) Under Causation and Manipulability is admits to the potential circularity:
von Wright responds as follows:
The connection between an action and its result is intrinsic, logical and not causal (extrinsic). If the result does not materialize, the action simply has not been performed. The result is an essential “part” of the action. It is a bad mistake to think of the act(ion) itself as a cause of its result. (pp. 67–8)
Here we see a very explicit attempt to rebut the charge that an account of causation based on agency is circular by contending that the relation between an action (or a human manipulation) and its result is not an ordinary causal relation.
Next section is A More Recent Version of an Agency Theory (of causation). It muses about the difference between “free agency” and causation in the usual philosophical ways, with no clear definition ever given. Here is a typical sentence:
The idea is thus that the agent probability of B conditional on A is the probability that B would have conditional on the assumption that A has a special sort of status or history—in particular, on the assumption that A is realized by a free act.
Further about this “free act”:
(What “free act” might mean in this context will be explored below, but I take it that what is intended—as opposed to what Price and Menzies actually say—is that the manipulation of X should satisfy the conditions we would associate with an ideal experiment designed to determine whether X causes Y—thus, for example, the experimenter should manipulate the position of the barometer dial in a way that is independent of the atmospheric pressure Z, perhaps by setting its value after consulting the output of some randomizing device.)
So a free act is an act of an “observer”, who is by definition an agent. I don’t know how to read this section charitably. It all seems very circular to me.
OK, let’s try the next section: Causation and Free Action:
It seems clear, however, that whether (as soft determinists would have it) a free action is understood as an action that is uncoerced or unconstrained or due to voluntary choices of the agent, or whether, as libertarians would have it, a free action is an action that is uncaused or not deterministically caused, the persistence of a correlation between A and B when A is realized as a “free act” is not sufficient for A to cause B.
OK, so what’s a “free act”? Alas, there is no definition anywhere in there, not that I can find. There is a related notion of “intervention”, which is somehow different from “free action”:
The simplest sort of intervention in which some variable Xi is set to some particular value xi amounts, in Pearl’s words, to “lifting Xi from the influence of the old functional mechanism Xi = Fi (Pai, Ui) and placing it under the influence of a new mechanism that sets the value xi while keeping all other mechanisms undisturbed.” (Pearl, 2000, p. 70; I have altered the notation slightly). In other words, the intervention disrupts completely the relationship between Xi and its parents so that the value of Xi is determined entirely by the intervention. Furthermore, the intervention is surgical in the sense that no other causal relationships in the system are changed. Formally, this amounts to replacing the equation governing Xi with a new equation Xi = xi, substituting for this new value of Xi in all the equations in which Xi occurs but leaving the other equations themselves unaltered. Pearl’s assumption is that the other variables that change in value under this intervention will do so only if they are effects of Xi.
Bummer, so an intervention is also defined in terms of some external “lifter” who “disrupts completely the relationship” and “replaces equations”. And that external lifter is presumably an agent. So, we are again, back to square one, what is an agent? Appropriately, the next section is called Is Circularity a Problem?:
Suppose that we agree that any plausible version of a manipulability theory must make use of the notion of an intervention and that this must be characterized in causal terms. Does this sort of “circularity” make any such theory trivial and unilluminating?
No, of course not, says the article, but how it justifies this conclusion is not at all clear to me. It muses about non-reductionism and how (emphasis mine)
Whether one regards the verdicts about these cases [something about a “failure of a gardener to water his plants”] reached by causal process accounts or by interventionist accounts as more defensible, the very fact that the accounts lead to inconsistent judgments shows that interventionist approaches are not trivial or vacuous, despite their “circular”, non-reductive character.
I don’t understand how they came to this conclusion, but fine, let’s see if there is anything at all that I can salvage from this entry. Another section talks about Interventions That Do Not Involve Human Action (emphasis mine):
a purely “natural” process involving no animate beings at all can qualify as an intervention as long as it has the right sort of causal history—indeed, this sort of possibility is often described by scientists as a natural experiment. Moreover, even when manipulations are carried out by human beings, it is the causal features of those manipulations and not the fact that they are carried out by human beings or are free or are attended by a special experience of agency that matters for recognizing and characterizing causal relationships. Thus, by giving up any attempt at reduction and characterizing the notion of an intervention in causal terms, an “interventionist” approach of the sort described under §§5 and 6 avoids the second classical problem besetting manipulability theories—that of anthropocentrism and commitment to a privileged status for human action.
So, it’s the “causal features” that matter but “not the fact that they are carried out by human beings” that matter, yet they still have to be caused by human beings at some point? Yep, back to the missing definition of agency, yet again.
So, my attempt to understand the intuitively obvious concept of agency using the accessible philosophical resources was a complete flop.