I am currently reading Brian Epstein’s book The Ant Trap (Oxford University Press). Epstein is Assistant Professor of Philosophy at Tufts University and is a specialist of social ontology and philosophy of social science more generally. Though I do not like the subtitle at all (“Rebuilding the Foundations of the Social Sciences”), the book provides an interesting and stimulating attempt to build a metaphysical framework for studying the social world. Epstein is mainly interested in working out the metaphysical reasons that ground social facts, i.e. what is it that makes facts like “I have a 20$ bill in my pocket” or “Barack Obama is the President of the United States of America” possible. The book has two parts: the first one develops the metaphysical framework on the basis of a critique of the “standard model of social ontology”. The second part applies the framework to the specific topic of groups and what ground facts about groups. A recurring theme throughout the book is the critique of ontological individualism, i.e. the claim that only facts about individuals ground social facts, including facts about groups.
In this post, I will only discuss Epstein’s key concept of frame principles. Epstein offers this concept as an alternative to Searle’s constitutive rules and it is instructive to see if and how it avoids the problems I discuss in my preceding post. Epstein’s framework builds on a key distinction between anchoring and grounding. This distinction is not essential here but helps to better understand both the critique of ontological individualism and Epstein’s points about the nature of social facts. Grounding is a relation between two facts through what the author calls a frame principle: it states the conditions (the “metaphysical reasons”) for a fact to generate another (social) fact. For instance, through a given frame principle, the (physical) fact that I raise my hand at some time and some place grounds the (social) fact that I have voted for some candidate in an election. Anchoring is different: it is “a relation between a set of facts and a frame principle” (p. 82). An anchor is what is making a given frame principle to hold in some population. The nature of the anchor may vary depending one’s favorite model of social ontology. For instance, in Searle’s account of institutional facts the anchor is the collective acceptance or recognition of some constitutive rules. Epstein does not much discuss anchoring but argues convincingly against the “conjunctivist” (scholars who conflate grounding and anchoring) that the distinction is important because it is the only way to avoid falling in an infinite regress.
For the rest of this post, I will ignore issues related to anchoring. The grounding relation is more significant because Epstein suggests that it is an alternative to Searle’s account of constitutive rules (which, according to the author, are “neither constitutive nor are they rules” (p. 77)). As said above, the grounding relation is a relation between two facts or set of facts. More exactly, it is established through a frame principle that articulates a link between a grounding (set of) condition(s) X and a grounded fact of type Y. This gives the following formula for a frame principle (p. 76):
For any z, the fact “z is X” grounds the fact “z is Y”.
Consider for instance the following frame principle:
For all z, the fact “z is a bill printed by the Bureau of Printing and Engraving” grounds the fact “z is a dollar”.
Given this frame principle, any fact of the type “this particular bill z* is printed by the bureau of Printing and Engraving” grounds the social fact “this particular bill z* is a dollar”. A frame principle can also be alternatively formulated in a semantic model of possible worlds: a frame is simply a set of possible worlds P where the grounding conditions for social facts are fixed. Denote w(z-X) and w(z-Y) as the propositions “In world w, the fact “z is X” holds” and “In world w, the fact “z is Y” holds” respectively. Then, if zX is the event “z is X” (i.e. the subset of possible worlds where the proposition w(z-X) is true), then zX ⊆ zY for all w ∈ P, with zY the event “z is Y”. In words, for any possible worlds where the frame holds, whenever z has property X, it also has property Y.
Epstein does not state clearly why his formulation his superior to Searle’s. One advantage is that it may help to make the distinction between grounding and anchoring more salient. In particular, it appears clearly that grounding is captured by a “possible worlds/unique frame” model, while anchoring corresponds a “unique world/possible frames” model. Another advantage is that it seems to rule out all the debates over the nature of rules. Epstein’s frame principles are not (necessarily) rules, so that to ask whether they are regulative or constitutive seems meaningless. Still, as far as I can see, the “linguistic argument” presented in the preceding post is still valid. The issues of the nature of (regulative) rules and of their differences with frame principles remain in Epstein’s framework. Does a regulative rule of the kind “In Britain, drive at the left side of the road” also counts as a frame principle? At first sight, it seems not. But the problem is that it is not difficult to reformulate any frame principle as a regulative rule along exactly the same lines that the one discussed in the preceding post. This is not surprising: Epstein’s frame principles are semantically identical to Searle’s constitutive rules (i.e. the underlying semantic model is the same). And any regulative rule can be captured by a similar semantic model. So the question of the nature of the grounding relation is not completely answered. Epstein’s account suggests nevertheless a possible direction to look at: it is possible that the more or less “constitutive” nature of frame principles depends on the conditions of their anchoring. That is a possibility that could be worth to be explored.
 Consider a regulative rule “if z is X, then z is Y” (e.g. if Bill is under 18, then Bill cannot vote”). Now, using the same notation than above, in all possible worlds w ∈ P where the rule holds, zX ⊆ zY.