Cedric Paternotte

Les concepts de sens commun et de connaissance commune, bien qu’intuitivement proches, divergent selon leurs analyses philosophiques traditionnelles. Le sens commun est polysémique et possède une dimension sociologique, tandis que la connaissance commune est un état épistémique collectif qui a reçu des définitions formelles. Cet article montre que ces divergences ne sont qu’apparentes en révélant plusieurs points de convergence significatifs entre les deux concepts. En particulier, le sens commun inclut souvent une connaissance commune ; et la connaissance commune ne saurait exister sans un certain sens commun sous-jacent. De façon secondaire, l’analyse montre par l’exemple que les différences entre les versions d’un concept en philosophie analytique formelle et en philosophie non formelle peuvent être artificielles et nuire à sa bonne compréhension.

There exist many definitions of human joint action, or of what makes a group similar to an individual. However, they do not agree and are not directly reducible to each other. This multiplicity is due to a lack of constraints on them. I argue that they should at least meet an efficiency constraint: any account of joint action has to justify how it reliably leads agents to cooperation. One avenue consists in exploring the analogy between definitions of joint action and of biological individuality. The main components for biological individuality have been identified and their relations are much better understood than those between the components of human joint action. I show that there are surprisingly strong analogies between the criteria and mechanisms for joint action and for biological individuality. As a result, we can import some insights of the biological literature to define what a joint action is, and when a group can and should be considered as an individual.

The repeated attempts to characterise joint action have displayed a common trend towards minimalism – whether they focus on minimal situations, minimal characterisations, cognitively minimal agents or minimal cognitive mechanisms. This trend also appears to lead to pluralism: the idea that joint action may receive multiple, equally valid characterisations. In this paper, I argue for a pluralist stance regarding joint action, although one stemming from maximalism. Starting from the description of three cases of "maximal" joint action – demonstrations, deliberations and free collective improvisation – that stretch our conceptual characterisations of joint action, I introduce and defend contextual minimalism, which focuses on joint actions occurring in contexts from which the factors that typically favour successful cooperation are absent. Although maximalist as compared to the other forms of minimalism, contextual minimalism does fit the minimalist trend and its recent emphasis on specific cognitive cooperative mechanisms.

There exist many competing philosophical definitions of joint action and no clear criteria to decide between them; so far the search for definitions has by and large been a semantical enterprise rather than an empirical one. This chapter describes and assesses several constraints that could help converge towards a set of necessary and sufficient conditions for joint action. The tightness constraint favours definitions that fit joint actions in which the links between agents are as relaxed as possible, so as to better pinpoint the conceptual core of jointness. The developmental constraint asks for definitions based on realistic psychological states that could be entertained by agents less cognitively developed than ideal human beings. The motor constraint holds that definitions should refer to psychological mechanisms involved in actual human coordination. These first three constraints are discussed and dismissed, mainly because they manage to establish vague limits at best (for various reasons). I then introduce a fourth one, the efficiency constraint, based on the fact that most of our joint actions are generally successful, and according to which definitions should involve conditions that help justify this success. Finally, the rational and evolutionary versions of the efficiency constraint are examined and defended against objections.

Marcher ensemble, porter une table à plusieurs, participer à une manifestation, et même discuter, sont autant d’exemples de coopération humaine – d’action conjointe. Par opposition, les mouvements d’une foule dans la rue, la course simultanée d’individus vers un abri lorsque l’orage se déclare ne sont que des actions collectives. Mais comment distinguer les unes des autres? Quand pouvons-nous dire que des personnes ont vraiment agi ensemble? Et comment expliquer qu’ils coopèrent même lorsque le risque d’échec est considérable? Cet ouvrage se propose de répondre à ces questions, en se penchant sur toutes les dimensions de la coopération : les buts collectifs, la connaissance commune, ainsi que les facteurs psychologiques, cognitifs et stratégiques qui la favorisent. À partir de notions telles que l’identification de groupe, on défendra en particulier la thèse que certains types d’actions de masse, comme les manifestations, peuvent constituer des exemples légitimes de coopération.