² On the relatively narrow sense of ‘group’, or ‘social group’, in question see On Social Facts, chapter 4. I also explore there the conditions for the appropriate use of the first person plural pronoun ‘we’, which had been neglected by theorists of other such expressions.

³ See for instance the essays in Schmitt, Frederick, ed., 1994, Socializing Epistemology, Rowman and Littlefield:Google Scholar Lanham, MD; see also, in Italian, , Esperienza e Cognoscenza, 1995, ed. Piazza, Gianguido, Milan: Citta Studi,Google Scholar which translates a number of texts that are generally taken to be contributions to social epistemology. Each of these collections includes at least one essay on a collective cognitive state, but the majority of the essays are concerned with other matters.

⁴ Deborah Tollefsen uses this phrase in a roughly similar way in a paper presented at Leipzig University, June 2004, “Collective Epistemic Agency and the Need for Collective Epistemology” (2004ms).

⁵ See, for instance, Charles Taylor, 1980, notice, Critical, Bennett's, JonathanLinguistic Behavior, Dialogue, vol. 19; Charles Taylor, 1985,Google ScholarHuman Agency and Language, Cambridge University Press: Cambridge,Google Scholar chapter 10, ‘Theories of Meaning’, section III.1. ‘Common knowledge’, undoubtedly an important topic for epistemology, has been variously defined. For present purposes what is important about these definitions is that they generally refer to individual human beings, what each knows, what each knows about each one's knowledge, and so on. Two classic sources are Lewis, David, 1969, Convention: A Philosophical Study, Harvard University Press: Harvard;Google Scholar and Schiffer, Stephen, 1972, Meaning, Oxford University Press: OxfordGoogle Scholar. See also Gilbert, Margaret, 1989, On Social Facts, Princeton University Press: PrincetonGoogle Scholar.

⁶ Margaret Gilbert, ‘Modeling Collective Belief’, 1987, Synthese, reprinted in Gilbert, Margaret, Living Together: Rationality, Sociality and Obligation, 1996, Rowman and Littlefield: Lanham, MD,Google Scholar and Gilbert, Social Facts. Due to the vagaries of publishing, the 1987 article was written after the 1989 book was sent to the press. I have developed my position in a number of subsequent publications including, most recently, ‘Belief and Acceptance as Features of Groups’, 2002, Protosociology, vol. 16, 35–69CrossRefGoogle Scholar.

⁷ Tuomela, Raimo, 1992, ‘Group beliefs’, Synthese vol. 91, 285–318,CrossRefGoogle Scholar responds to my proposals in ‘Modeling’ and Social Facts and presents an alternative but in many ways similar account. See also his book The Importance of Us, 1995, Stanford University Press: StanfordGoogle Scholar. Other philosophers who have addressed one or more aspects of the topic in the 1990s or later include, in alphabetical order, Alban Bouvier, Austen Clark, Angelo Corlett, Christopher MacMahon, Anthonie Meijers, Philip Pettit, Gianguido Piazza, Gerhard Preyer, Abraham Sesshu Roth, Frederick Schmitt, Deborah Tollefsen and Bradley Wray. Preyer edits the online journal Protosociology in which relevant publications by a number of these authors have recently appeared in special issues: web address: www.protosociology.de.

⁸ Relatively few of the authors mentioned in the last footnote specialize in mainstream epistemology.

⁹ See Durkheim, Emile, 1982, The Rules of Sociological Method, translated from the French by Halls, W. D., Free Press: New YorkCrossRefGoogle Scholar (first published 1895). I suggest an interpretation of key passages in this work in On Social Facts, chapter 5, and subsequently in ‘Durkheim and Social Facts’, 1994, in Debating Durkheim, Martins, Herminio and Pickering, William, eds., Routledge: London,Google Scholar reprinted in French translation in Gilbert, Margaret, Marcher Ensemble: Essais sur les Fondements de la Vie Collective, 2003, Presses Universitaires de France: Paris.Google Scholar As I interpret him Durkheim presents us with an intriguing, nuanced proposal that requires further elaboration. My own proposals on the topic indicate one way in which such elaboration out might proceed.

¹⁰ In On Social Facts I referred to my approach as ‘conceptual analysis’, a phrase open to various construals. The preceding description of my approach may be less tendentious. The main point is that everyday judgments about when, say, a group believes something, and when it fails to believe something are carefully considered to arrive at a description of what (according to everyday understandings) collective belief is. No substantive ‘theory of concepts’ is presupposed.

¹¹ Angelo Corlett pays attention to the question of collective knowledge in his book Analyzing Social Knowledge, 1996, Rowman and Littlefield: Lanham, MAGoogle Scholar.

¹² See, for instance, Quinton, Anthony, 1975, ‘Social Objects’, Proceedings of the Aristotelian Society, vol. 75Google Scholar. Quinton assumes the simple summative account en passant. Related assumptions have been made for specific forms of belief or judgement, such as moral judgement. On this see Margaret Gilbert, ‘Shared Values, Social Unity, and Liberty’, forthcoming in Public Affairs Quarterly, e.p.d. January 2005.

¹³ More extensive discussions are to be found in Gilbert, ‘Modeling’, and Gilbert, Social Facts.

¹⁴ I develop an example involving a poetry discussion group in more detail in Gilbert, ‘Modeling’. The example derives from an actual, unexpectedly long-standing group founded by the author together with Mairie McInnes and Priscilla Barnum.

¹⁵ I take interpersonal discussions generally to be a form of acting together or collective action. I offer accounts of such action in On Social Facts, chapter 4, and elsewhere. See, for instance, ‘What is it for Us to Intend?’ 1997, in Contemporary Action Theory, vol. 2Google Scholar, The Philosophy and Logic of Social Action, Holmstrom-Hintikka, G. and Tuomela, R., eds, reprinted in Margaret Gilbert, 2000,Google ScholarSociality and Responsibility: New Essays in Plural Subject Theory, Rowman and Littlefield: Lanham, MDGoogle Scholar. These accounts are formally similar to the account of collective belief sketched here.

¹⁶ For an example of how there might be a complete lack of corresponding personal beliefs see Gilbert, Social Facts, p.290.

¹⁷ This might not be so in special circumstances. For instance, the group has previously opined that a given poet is so talented he is incapable of writing a poem that is less than brilliant.

¹⁸ See Gilbert, ‘Modeling’; also ‘Remarks’.

¹⁹ Cf. Hart, H. L. A., 1961, The Concept of Law, Clarendon Press: OxfordGoogle Scholar. Hart sees ‘informal reproofs’ and legal punishment as in the same category.

²⁰ For related discussion see Gilbert, ‘Modeling’; Gilbert, Social Facts, Chapter 5.

²¹ For detailed discussion and critique of two such complex summative accounts see Gilbert, Social Facts, Chapter 5.

²² I have formulated this account differently on different occasions. Essentially the same idea is expressible in different ways. The Introduction to my book Living Together: Rationality, Sociality, and Obligation, 1996, Rowman and Littlefield: Lanham, MD, pp. 7–10,Google Scholar explains the way the main formulations I have used relate to one another. See also Gilbert, Social Facts, Chapter 7, on different formulations of the general schema of which this is an exemplification.

²³ Other theorists have used the same phrase; sometimes they have not indicated what they mean by it; at other times the sense explicitly given has been different to the one I give. In any case I am concerned with joint commitment in my own technical sense here.

²⁴ For a more extended discussion see the Introduction to Living, pp. 7-15.

²⁵ See Gilbert, Margaret, Social Facts, Living, and Sociality and Responsibility: New Essays in Plural Subject Theory, 2000, Rowman and Littlefield: Lanham, MDGoogle Scholar.

²⁶ For more on such commitments see Gilbert, Margaret, forthcoming, ‘Towards a Theory of Commitments of the Will: On the Nature and Normativity of Intentions and Decisions’, Rabinowicz, Wlodek, ed., Patterns of Value 2, Lund University: LundGoogle Scholar. For a distinction between ‘reasons’ and ‘rational requirements’ see Broome, John, ‘Are Intentions Reasons? And How Should we Cope with Incommensurable Values?’, 2001, in Practical Rationality and Preference: Essays for David Gauthier, eds. Morris, Christopher and Ripstein, Arthur, Cambridge University Press: Cambridge, pp. 98–120CrossRefGoogle Scholar.

²⁷ On this see Margaret Gilbert, 1999, ‘Obligation and Joint Commitment’, Utilitas, reprinted in Gilbert, Sociality; this cites Kenny, Anthony, 1963, Action, Emotion, and Will, Routledge and Kegan Paul: LondonGoogle Scholar.

²⁸ For a more extended discussion of joint commitment see Gilbert, Margaret, 2003, ‘The Structure of the Social Atom: Joint Commitment as the Foundation of Human Social Behavior’, in Schmitt, Frederick, ed., Social Metaphysics, Rowman and Littlefield: Lanham, MD;Google Scholar see also the Introduction, Living, pp. 7-15, and ‘Obligation’.

²⁹ For discussion of the consequences of such violation see the Introduction, Living, pp. 14-15. I there incline to the view that generally speaking violation by one or more parties renders a joint commitment rescindable by the remaining parties, as opposed to nullifying it.

³⁰ I focus on the relationship of joint commitment and rights in my book Rights Reconsidered, to be published by Oxford University Press.

³¹ See Gilbert, ‘Obligation’, and elsewhere.

³² For discussion of the distinctiveness of these obligations see my article ‘Agreements, Coercion, and Obligation’, Ethics, 1993, vol. 103,Google Scholar reprinted with some revisions in Living.

³³ I assume here that a rebuke is the after-the-fact correlate of a demand.

³⁴ See Gilbert, Social Facts, Living, and other writings.

³⁵ I emphasize the point in response to various comments.

³⁶ For more on this see the text below.

³⁷ See Margaret Gilbert, ‘Shared Values, Social Unity, and Liberty’, forthcoming in Public Affairs Quarterly, e.p.d. January 2005.

³⁸ On the question of context see also Gilbert, Margaret, ‘Remarks on Collective Belief’, 1994, in Schmitt, Frederick, ed., Socializing Epistemology, Rowman and Littlefield: Lanham, MDGoogle Scholar (revised as ‘More on Collective Belief’ in Living).

³⁹ For further discussion of the role of collective beliefs in science see Gilbert, 2000, Sociality, chapter 3, ‘Collective Beliefs and Scientific Change’, first published in Italian in 1998.

⁴⁰ I make this point in response to a query from the developmental psychologist Letitia Nagles in discussion at a University of Connecticut cognitive science colloquium. A related point was brought up by the anthropologist Maurice Bloch in discussion at a roundtable on collective belief held at the Sorbonne, Paris.

⁴¹ See, for instance, Wray, K. Bradley, 2002, ‘Collective Belief and Acceptance’, Synthese, 129: 319–333;CrossRefGoogle ScholarMeijers, Anthonie, 1999, ‘Believing and Accepting as a Group’, in Belief, Cognition and the Will, ed. Meijers, A.. Tilburg: Tilburg University Press. 59–71;Google Scholar also Meijers, A., 2002, ‘Collective Agents and Cognitive Attitudes’, Protosociology, 16: 70–86CrossRefGoogle Scholar.

⁴² See Gilbert, ‘Belief and Acceptance’.

⁴³ See Wray, K. Bradley, 2003, ‘What Really Divides Gilbert and the Rejectionists’, Protosociology 17,Google Scholar and related papers, in the same volume, by Christopher MacMahon, Anthonie Meijers, Deborah Tollefsen. See also Abraham Sesshu Roth, 2003ms, ‘Remarks on Collective Belief and Acceptance’.

⁴⁴ See Gilbert, ‘Belief and Acceptance’.

* A version of this paper, ‘Collective Belief as a Subject for Cognitive Science’, was given to the cognitive science group at the University of Connecticut, Storrs, CT, February 14 2003, and to the Roundtable on Collective Belief at the Sorbonne, Paris, April 4 2003. I thank those present for discussion, and Ludger Jansen for some pertinent conversation on a related topic, August 2004.