Groups behave in a variety of ways. To show that this behavior amounts to action, it would be best to fit it into a general account of action. However, nearly every account from the philosophy of action requires the agent to have mental states such as beliefs, desires, and intentions. Unfortunately, theorists are divided over whether groups can instantiate these states—typically depending on whether or not they are willing to accept functionalism about the mind. But we can avoid this debate. (...) I show how a more general view of action captures what is central to action without mentioning mental states, and I argue that a group’s members can fulfill the role in group action that mental states play in our actions. Group behavior is explicable in terms of reasons, regardless of whether the group itself cognizes those reasons. After discussing the kind of reasons at issue and arguing that groups can act in light of them without minds, I assess how this account bears on the question of group responsibility. (shrink)

Given a group , G⊆Mm, definable in a first-order structure equation image equipped with a dimension function and a topology satisfying certain natural conditions, we find a large open definable subset V⊆G and define a new topology τ on G with which becomes a topological group. Moreover, τ restricted to V coincides with the topology of V inherited from Mm. Likewise we topologize transitive group actions and fields definable in equation image. These results require a series of preparatory facts concerning (...) dimension functions, some of which might be of independent interest. (shrink)

In recent years there has been an interesting turn in the philosophical literature to groups and collective action. At the same time there has been a renewed interest in various forms of methodological individualism. This paper attempts to show the diversity of group action that is overlooked by much of the literature, to clarify some of the ambiguities that plague our language about groups and collectives, and to support the view that social entities are genuine. Some important arguments against social (...) entities being genuine are rebutted. The existence of social entities gives some substance to the debate about methodological individualism, but the resolution of the debate has depended too much on empirical results in the distant future. The article ends with some suggestions on how the debate matters in looking for biases in the directions of current social theorizing. (shrink)

We extend a theorem of Barwise and Nadel describing the relationship between approximations of canonical Scott sentences and admissible sets to the case of orbit equivalence relations induced on an arbitrary Polish space by a Polish group action.

In this paper a social group’s (retrospective) responsibility for its actions and their consequences are investigated from a philosophical point of view. Building on Tuomela’s theory of group action, the paper argues that group responsibility can be analyzed in terms of what its members (jointly) think and do qua group members. When a group is held responsible for some action, its members, acting qua members of the group, can collectively be regarded as praiseworthy or blameworthy, in the light of some (...) normative standard, for what the group has done. The paper gives a necessary and sufficient conditions analysis of a group’s responsibility for its actions and their outcomes, and the conditions can be cashed out in terms of the group members’ joint (and other) actions. (shrink)

Presents a unified semantics for various readings of 'together', using event mereology.

We interpret the basic notions of topological dynamics in the model-theoretic setting, relating them to generic types of definable group actions and their generalizations.

We study the situation when the automorphism group of a recursively saturated structure acts on an ℝ-tree. The cases of and models of Peano Arithmetic are central in the paper.

Let G be a closed subgroup of S∞ and X be a Polish G -space. To every x ∈ X we associate an admissible set Ax and show how questions about X which involve Baire category can be formalized in Ax.

The paper argues that there are two main kinds of joint action, direct joint bringing about (or performing) something (expressed in terms of a DO-operator) and jointly seeing to it that something is the case (expressed in terms of a Stit-operator). The former kind of joint action contains conjunctive, disjunctive and sequential action and its central subkinds. While joint seeing to it that something is the case is argued to be necessarily intentional, direct joint performance can also be nonintentional. Actions (...) performed by social groups are analyzed in terms of the notions of joint action (basically DO and Stit).A precise semantical analysis of the aforementioned kinds of joint action is given in terms of time-trees. With each participant a tree is connected, and the trees are joined defining joint possible worlds in terms of state-expressing nodes from the trees. Sentences containing DO and Stit are semantically evaluated with respect to such joint possible worlds. Intentional joint actions are characterized in terms of the notion of we-intention (joint intention), characterized formally by means of a special operator. (shrink)

We study model theory of actions of finite groups on substructures of a stable structure. We give an abstract description of existentially closed actions as above in terms of invariants and PAC structures. We show that if the corresponding PAC property is first order, then the theory of such actions has a model companion. Then, we analyze some particular theories of interest (mostly various theories of fields of positive characteristic) and show that in all the cases considered the PAC property (...) is first order. (shrink)

In this paper I analyze the nature of groups and collective actions, focusing primarily upon those groups that do not possess either a formal organizational structure or formalized decision procedures. I argue that the unity relation for all groups is a common interest and that the existence of this common interest makes even informal groups specific and enduring entities which can act and be acted upon.In light of this discussion, I proceed to examíne the issue of affirmative action programs and (...) policies of preferential treatment. I argue that by utilizing my theory of groups the most serious objections to such policies --- viz., that they unjustly discriminate against innocent and arbitrarily selected white males in favor of undeserving and arbitrarily selected African Americans and women --- are shown not to be applicable. These objections depend upon reducing groups to their constituent individuals whereas I maintain that some groups ought to be treated as entities themselves. (shrink)

Let G be a finite group. We explore the model-theoretic properties of the class of differential fields of characteristic zero in m commuting derivations equipped with a G-action by differential fie...

In this paper I analyze the nature of groups and collective actions, focusing primarily upon those groups that do not possess either a formal organizational structure or formalized decision procedures. I argue that the unity relation for all groups is a common interest and that the existence of this common interest makes even informal groups specific and enduring entities which can act and be acted upon.In light of this discussion, I proceed to examíne the issue of affirmative action programs and (...) policies of preferential treatment. I argue that by utilizing my theory of groups the most serious objections to such policies --- viz., that they unjustly discriminate against innocent and arbitrarily selected white males in favor of undeserving and arbitrarily selected African Americans and women --- are shown not to be applicable. These objections depend upon reducing groups to their constituent individuals whereas I maintain that some groups ought to be treated as entities themselves. (shrink)

It is shown that for invariance under the action of special groups the statements "Every invariant PCA is decomposable into (1 invariant Borel sets" and "Every pair of invariant PCA is reducible by a pair of invariant PCA sets" are independent of the axioms of set theory.

In this paper, we continue the construction done in [3], so that under model-4-CA or 4-CA, given a bounded quadrangle C induced from a group configuration, we build a canonical hyperdefinable homogeneous space equivalent to C. When C is principal, we can choose the homogeneous space principal as well.

We study algebraic and model-theoretic properties of existentially closed fields with an action of a fixed finite group. Such fields turn out to be pseudo-algebraically closed in a rather strong sense. We place this work in a more general context of the model theory of fields with a group scheme action.

This article endorses a familiar, albeit controversial, argument for the existence of group-based reasons for action, but then rejects two doctrines which other advocates of such reasons usually accept. One such doctrine is the willingness requirement, which says that a group-based reason exists only if (sufficient) other members of the group in question are willing to cooperate. Thus the paper argues that there is sometimes a reason, which derives from the rationality of some group action, to play one's part unilaterally (...) in that group action. This seems implausible only because we tend wrongly to accept a second doctrine, monism about the unit of agency. Monism claims that, for any given deliberative problem, there is only one unit of agency to which reasons attach. If we are monists who believe in group-based reasons, the willingness requirement will seem necessary in order to avoid recklessness. We should reject monism, and if we do so we can recognise genuine conflict between individual-based and group-based reasons, and in doing so we can explain, without endorsing the willingness requirement, why we should not act recklessly. (shrink)

An important thesis discussed in the literature on shared agency is that group identification motivates pre-school children to act together. This paper aims at further illuminating this thesis by clarifying what triggers the process of group identification in young children. It is argued that joint attention, among other functions in supporting joint actions, can reveal to the co-attenders that they share some preferences. Since sharing preferences has been established by the literature to be a reliable motivation of group identification and (...) since joint attention has an early emergence in development, one can consider joint attention to be a putative trigger of group identification in pre-school children. If this is on the right track, group identification, joint attention, and preferences identify a cluster of minimal pre-conditions for joint actions. (shrink)

Actions are usually generalized among social group members. Importantly, the efficiency of an action with respect to achieving an external target determines action understanding, and it may have different degrees of social relevance to social groups. Thus, this study explored the role of action efficiency in action generalization. We used computer animations to simulate actions in social groups initiated by visual action cues or category labels, and we measured differences in response times between identifying actions that were and were not (...) consistent with group members, without explicit requirements regarding generalization. It was found that in both visually introduced and explicitly labeled social groups, when the group members acted inefficiently toward the external object, perceivers identified group‐consistent actions faster than group‐inconsistent actions, indicating that the exemplars' common inefficient actions are generalized to the unknown ingroup member, accordingly facilitating the identification of expected consistent inefficient action (Experiment 1). As this effect was not present when removing social group cues, it was determined to be specific to social groups (Experiment 2). Importantly, such generalization was not observed when the identical action was deemed efficient toward the external object (Experiment 3) and was specific to the demonstration of the action being completed by multiple group members rather than being repeated twice by one group member, supporting the group‐based inference and ruling out the possibility of the increased memorability of inefficient actions leading to more generalization relative to efficient actions (Experiment 4). Therefore, the efficiency of an action bounds the generalization of the action across social group members through a process that is spontaneous and implicit. This constrained action generalization may be due to inefficient actions being represented as culture‐specific conventional forms. (shrink)

Contemporary philosophers and scientists have done much to expand our understanding of the structure and neural mechanisms of joint action. But the phenomenology of joint action has only recently become a live topic for research.One method of clarifying what is unique about the phenomenology of joint action is by considering the alternative perspective of agents subsumed in group action. By group action we mean instances of individual agents acting while embedded within a group agent, instead of with individual coordination. Paradigm (...) examples are educational bureaucracies, corporations, and nation states. There is a phenomenological difference between agents whose actions are subsumed within a group action as compared to agents who act jointly. Attending to this difference clarifies what is phenomenologically distinctive about joint action.Appealing to an Aristotelian account of agency and to the metaphysical concept of weak emergence, we argue that what makes paradigmatic group action distinctive is the relative inaccessibility, un-revisability, and evaluative simplicity of the group agent’s goal from the perspective of individual agents. This suggests that a distinctive feature of joint agency is the maintenance of a greater sense of individual agency. Put simply, joint agency is often experienced as an enhancement of the individuals’ agency precisely because our paradigmatic agential powers are extended intersubjectively as we act together. In contrast, group agency often involves a loss of the sense of agency, precisely because it is the emergent group agent that maintains the agential powers. (shrink)

University of Cologne, Germany Joint action and group agency have emerged as focuses of attention in recent social theory and philosophy but they have rarely been connected with one another. The argument of this article is that whereas joint action involves people acting together to achieve any sort of result, group agency requires them to act together for the achievement of one result in particular: the construction of a centre of attitude and agency that satisfies the usual constraints of consistency (...) and rationality in adequate measure. The main discovery in the recent theory of group agency is that this result is not easily achieved; no regular voting procedure will ensure, for example, that a group of individually consistent agents will display consistency in group judgments. Key Words: groups • group agents • collective agents • joint action • joint intention. (shrink)

People implicitly generalize the actions of known individuals in a social group to unknown members. However, actions have social goals and evaluative valences, and the extent to which actions with different valences (helpful and harmful) are implicitly generalized among group members remains unclear. We used computer animations to simulate social group actions, where helping and hindering actions were represented by aiding and obstructing another's climb up a hill. Study 1 found that helpful actions are implicitly expected to be shared among (...) members of the same group but not among members of different groups, but no such effect was found for harmful actions. This suggests that helpful actions are more likely than harmful actions to be implicitly generalized to group members. This finding was replicated in Study 2 by increasing the group size from three to five. Study 3 found that the null effect for generalizing harmful actions among group members is not due to the difficulty of detecting action generalization, as both helpful and harmful actions are similarly generalized within particular individuals. Moreover, Study 4 demonstrated that weakening social group information resulted in the absence of implicit generalization for helpful actions, suggesting the specificity of group membership. Study 5 revealed that the generalization of helping actions occurred when actions were performed by multiple group members rather than being repeated by one group member, showing group-based inductive generalization. Overall, these findings support valence-dependent implicit action generalization among group members. This implies that people may possess different knowledge regarding valenced actions on category-based generalization. (shrink)

If group members aim to fulfill a collective obligation, they must act in such a way that the composition of their individual actions amounts to a group action that fulfills the collective obligation. We study a strong sense of joint action in which the members of a group design and then publicly adopt a group plan that coordinates the individual actions of the group members. We characterize the conditions under which a group plan successfully coordinates the group members' individual actions, (...) and study how the public adoption of a plan changes the context in which individual agents make a decision about what to do. (shrink)

We show that each non-compact Polish group admits a continuous action on a Polish space with non-smooth orbit equivalence relation. We actually construct a free such action. Thus for a Polish group compactness is equivalent to all continuous free actions of this group being smooth. This answers a question of Kechris. We also establish results relating local compactness of the group with its inability to induce orbit equivalence relations not reducible to countable Borel equivalence relations. Generalizing a result of Hjorth, (...) we prove that each non-locally compact, that is, infinite dimensional, separable Banach space has a continuous action on a Polish space with non-Borel orbit equivalence relation, thus showing that this property characterizes non-local compactness among Banach spaces. (shrink)

This article argues against the view that affirmative action is wrong because it involves assigning group rights. First, affirmative action does not have to proceed by assigning rights at all. Second, there are, in fact, legitimate “group rights” both legal and moral; there are collective rights—which are exercised by groups—and membership rights—which are rights people have in virtue of group membership. Third, there are continuing harms that people suffer as blacks and claims to remediation for these harms can fairly treat (...) the (social) property of being black as tracking the victims of those harms. Affirmative action motivated in this way aims to respond to individual wrongs; wrongs that individuals suffer, as it happens, in virtue of their membership in groups. Finally, the main right we have when we are being considered for jobs and places at colleges is that we be treated according to procedures that are morally defensible. Morally acceptable procedures sometimes take account of the fact that a person is a member of a certain social group. (shrink)

A Polish group G is tame if for any continuous action of G, the corresponding orbit equivalence relation is Borel. When [Formula: see text] for countable abelian [Formula: see text], Solecki [Equivalence relations induced by actions of Polish groups, Trans. Amer. Math. Soc. 347 (1995) 4765–4777] gave a characterization for when G is tame. In [L. Ding and S. Gao, Non-archimedean abelian Polish groups and their actions, Adv. Math. 307 (2017) 312–343], Ding and Gao showed that for such G, the (...) orbit equivalence relation must in fact be potentially [Formula: see text], while conjecturing that the optimal bound could be [Formula: see text]. We show that the optimal bound is [Formula: see text] by constructing an action of such a group G which is not potentially [Formula: see text], and show how to modify the analysis of [L. Ding and S. Gao, Non-archimedean abelian Polish groups and their actions, Adv. Math. 307 (2017) 312–343] to get this slightly better upper bound. It follows, using the results of Hjorth et al. [Borel equivalence relations induced by actions of the symmetric group, Ann. Pure Appl. Logic 92 (1998) 63–112], that this is the optimal bound for the potential complexity of actions of tame abelian product groups. Our lower-bound analysis involves forcing over models of set theory where choice fails for sequences of finite sets. (shrink)

Large Groups are not constituted simply by adding further members to small groups. There is a qualitative difference between the social actions which take place in small communities and those in large ones. Large communities are irreducibly characterized by anonymity, i.e., the members of large groups don’t know of most of the other members as individual. Therefore, social action in large groups is based on a sign process: each member of a large group is understood as a representative of the (...) other anonymous members of the group as well as a sign for the group as a whole. (shrink)

A consensus has emerged among many normative theorists of cultural pluralism that dialogue is the key to securing just relations among ethnic or cultural groups. However, few normative theorists have explored the conditions or incentives that enable inter-group dialogue versus those that encourage inter-group conflict. To address this problem, I use Habermas’s distinction between communicative and strategic action, since many models of inter-group dialogue implicitly rely upon communicative action, while many accounts of inter-group conflict rest upon strategic action. Drawing on (...) explanatory accounts of inter-group conflict, I outline five strategic logics of group conflict, what I call the resource, political, information, positional, and security logics. I then argue that these strategic logics cannot be overcome by three motivations commonly thought to support communicative action: moral-cognitive consistency, the normative characteristics of modernity, and publicity constraints. At this point, I turn to an empirical case, the reception of African-American concerns within the Jewish public sphere prior to the Second World War, in order to suggest that, although strategic incentives might hinder inter-group dialogue, they may also encourage it. In conclusion, I provide three recommendations for how theorists might utilize strategic incentives in order to recognize which actors, policies, or institutions can encourage inter-group dialogue. (shrink)

We classify actions of groups of finite Morley rank on abelian groups of Morley rank 2: there are essentially two, namely the natural actions of SL(V) and GL(V) with V a vector space of dimension 2. We also prove an identification theorem for the natural module of SL₂ in the finite Morley rank category.

The following paper continues discussions within this journal about how the work of Delueze and Guattari can inform radical pedagogy. Building primarily on Noel Gough's 2004 paper, we take up the challenge to move towards a more creative form of 'becoming cyborg' in our teaching. In contrast to work that has focused on Deleuzian theories of the rhizome, we deploy Guattari's work on institutional schizoanalysis to explore the role of group creativity in radical pedagogy. The institutional therapies of Felix Guattari's (...) schizoanalytic practice in the 1950s and 1960s and, before him, the Francophone educationalist Celestin Freinet, who founded the Modern School Movement, are explored and used to illuminate examples of some of our own attempts to set the classroom up as a space for collective engagement. We conclude by exploring how this understanding of the class as subject group may be used to mobilise action and de-stabilise the coordinates of existing academic divisions of labour. (shrink)