Is joint action necessarily based on shared intention? Nicolas Lindner & Gottfried Vosgerau Department of Philosophy - Heinrich-Heine-Universität Düsseldorf KogWis2014: How Language and Behavior Constitute Cognition Tübingen So, if you heard Natalie Sebanz great plenary talk on Monday, you might remember that she willingly left two puzzle pieces out of her picture of joint action. Shared intenions and Social Cognition – and these are basically the two main aspects I will be talking about today. The title of my talk today is „Is joint action necessarily based on shared intention“. In this talk I want to invesitigate whether a leading account of collective intentionality by Michael Bratman succeeds in explaining all varieties of joint action sufficiently.

Acting together comes in many forms Acting together comes in many forms. From spontaneous and simple examples like TAKING A WALK TOGETHER..

..to more complex and coordinated ones like DANCING A TANGO..

..to highly sophisticated actions with many participants like A SYMPHONIC ORCHESTRA PLAYING A CLASSICAL PIECE OF MUSIC:

…and many, many more! …

There are also early and basic forms that are widely regarded as joint action and occur at the beginning of life – a child playing with an adult…

Or together with her peers..

Those kinds of early joint action have recently become the focus of attention for theses that regard cooperation as the cradle of human cognitive development. First and foremost, this line of thought has been advocated by Michael Tomasello and colleagues. Their idea is summed up in the following quote, which is the first line of his influential 2005 paper. Here he writes, and I quote: “We propose that the crucial difference between human cognition and that of other species is the ability to participate with others in collaborative activities with shared goals and intentions: shared intentionality.” (Tomasello et al. 2005)

Coming Attractions Bratman‘s Account of Shared Intention Criticisms of Bratman‘s Account and Children‘s Joint Action A New Approach – Acquiring the Concept of Intention Summary With regard to a philosophical account of joint action Tomasello mostly draws on Bratman’s account of shared intention – as many accounts of JA in cognitive science. So, this lead us to the following procedure in our talk. First of all, I will give a brief introduction to shared intention. Then, I will present criticisms regarding the explanatory scope of this account regarding children’s joint action. In the next part, I will present our original account of children’s joint action and –in the end- I will wrap everything up.

Bratman‘s Account of Shared Intention (SI) Bratman proposes a Reductive, functionalist, constructivist account of SI SI construed of interrelated individual intentions / attitudes of the participants Small-scale activities Only a pair of participants Non-asymmetric authority relations Follows a two-fold strategy Characterising the role of shared intention Giving a substantial account of / sufficient conditions for SI

The Role of Shared Intention Three interrelated jobs: Help coordinate our intentional actions E.g. Scrape paint off before, not after, new paint is applied Help coordinate our planning E.g. Check whether you get the brushes when I plan on getting the paint Structure relevant bargaining E.g. Bargaining when conflicts about who scrapes and who paints occur Doing these jobs is a necessary condition for any construction of SI

Sufficient Conditions for Shared Intention We intend to J if and only if (a) I intend that we J and (b) you intend that we J I intend that we J in accordance with and because of 1a, 1b, and meshing subplans of 1a and 1b; you intend that we J in accordance with and because of 1a, 1b, and meshing subplans of 1a and 1b. 1 and 2 are common knowledge between us. (Bratman 1993)

The Common Knowledge (CK) Condition Bratman often uses a rather unanalysed notion of CK: “[…]in shared intention the fact that each has the relevant attitudes is itself out in the open, is public” (Bratman 1993) “In SCA the fact that there is this mutually uncoerced system of intentions will be in the public domain.” (Bratman 1992) CK in Shared Agency: Mutual knowledge of the others‘ intentions plus knowledge of the others‘ knowledge „[…] it is common knowledge among A and B that p just when (a) A knows that p, (b) B knows that p, (c) A knows that B knows that p, (d) B knows that A knows that p, (e) A is in an epistemic position to know that (d), (f) B is an epistemic position to know that (c), and so on.“ (Bratman 2014) Bratman: unanalysed notion of common knowledge – a bit metaphorical. Only ‘epistemic position’ – not what participants explicitly know! CK about intention&belief, not vast deep of others’ mind. No CK of shared intention, because no circularity wanted

The Cognitive Basis for Common Knowledge Ability to form beliefs Ability to form beliefs about beliefs Mental state attribution (oneself and others) Recursive mindreading Robust theory of mind!

Is SI Too Demanding? Criticisms stating SI is cognitively too demanding (Tollefsen 2005, Pacherie 2011) Robust T.o.M. not developed before the age of four (false-belief task) Children engage in joint action much earlier Si cannot account for children’s joint action Problems of these criticisms: Controversial empirical claims Bratman’s substantial account aims at sufficient conditions “Constructivism aims at sufficient conditions for shared intention. It allows for the possibility that there are multiple constructions, […] the best thing to say, in the end, may be that shared intention is multiply realizable” (Bratman 2009) Young children engage in different forms of joint action: with adults from around 18 months of age & from the end of 2nd year of life also with peers (Brownell 2011) Onset of possession of robust T.o.M. (Baillargeon et al. 2010; De Bruin/Newen 2012) (Early) Understanding of common ground / common knowledge (Carpenter 2009; Liszkowski, Carpenter, & Tomasello 2008; Tomasello & Haberl 2003)) Development of mentalizing and meta-representational abilities

Does SI Presuppose What It Should Help Explain? Butterfill (2012) Joint action regularly used to explain early development of understanding of minds: “…the unique aspects of human cognition … were driven by, or even constituted by, social cooperation.” (Moll & Tomasello 2007) “The motivations and skills for participating in this kind of “we” intentionality are woven into the earliest stages of human ontogeny and underlie young children’s developing ability to participate in the collectivity that is human cognition” (Tomasello et al. 2005) Ideas on cooperation rest upon Bratman’s construction of SI Bratman’s “Shared Cooperative Activity” (1992)

Roles of SI and Understanding of Other Minds I Butterfill’s objection focuses on functional roles / necessary conditions for SI Help coordinate our intentional actions Help coordinate our planning Structure relevant bargaining Coordinating & bargaining doesn’t always require intentions which refer to other intentions Coordination of intentions often based on a shared background (preferences, habits & conventions) Bratman’s account of SI builds on Individual planning agency - Planning: coordinate agent’s various activities over quite long intervals of time – practical reasoning&forming intentions, possibly require futher planning & generating hierarchy of plans and subplans EXAMPLE: Giving a talk in a conference like this

Roles of SI and Understanding of Other Minds II In some cases monitoring or manipulating others’ intentions is required Novel aims / unusual circumstances / unfamiliar partners Lack of sufficient background Joint action of young children involves said aspects Joint action would presuppose psychological concepts whose development it should explain Early joint action of children cannot involve Bratman’s SI According to Tomasello & the likes

Is Bratman’s Account Incorrect? Bratman’s account cannot explain children’s joint action Other construction won’t do – necessary conditions cannot be met Problematic for approaches that regard joint action / cooperation as pivotal for development of cognitive / socio-cognitive abilities Explains joint action of mature cognitive agents Planning Future-directed intentions Stability and rationality of plans (norms) Deliberation

An Alternative Account of Children’s Joint Action Pictures of children who obviously fail at playing hide and seek. Seemingly, this is so because they cannot abstract from their own perspective. I hope you will see how this is related to our approach in a few seconds…

Children’s JA Grounded in Other Abilities Lack of the concept of a mental state (esp. intentions) produces behaviour that looks like JA If a child hasn’t learned that a mental state is something that ‘belongs’ to single persons the concept of a mental state is not acquired She might be able to introspect the content of her own intentions – paraphrased: ‘there is the intention to J’

Children’s JA Grounded in Other Abilities Child hasn’t developed the ability to differentiate between own intentions and those of others Effect of this lack will result in behaviour that looks like JA In cases where intentions of child and adults match Matching might be triggered by aspects of the environment: e.g. pointing gestures, affordances or alignment

Empirical Evidence in Favour of Our Account Acquisition of concepts of mental states depends on the use of mental state terms (Rakoczy, Tomasello and Striano 2006) Comprehension of mental state language correlates to T.o.M. abilities (Grazani/Ornaghi 2012) Mental state discourse is related to T.o.M. development, in particular the development of representational models of self / other as distinctive mental agents (Symons 2004)

Advantages of Our Account Specifies how (seemingly) JA might be pivotal to the development of socio-cognitive abilities: JA-like scenarios create environment that helps children to gradually learn that intentions can differ between individuals Learning phase results in acquisition of the concept of a mental state Learning of a T.o.M. starts with acquisition of a concept of a mental state This can be best acquired in (seemingly) JA scenarios, in which children directly experience effects of differing mental states (intentions / beliefs)

Summary Bratman’s account of SI not suited to explain early (seemingly) JA of children if it is pivotal for development of socio-cognitive abilities Accurately describes JA of cognitively mature agents (planning and deliberation) Our approach takes pivotal role of JA for socio-cognitive development into account Shows how learning phase of early forms of acting together fosters acquisition of mental state concepts Once these concepts are acquired, a T.o.M. can be learned and JA involving SI is possible

References Baillargeon, R., Scott, R. M., & He, Z. (2010). False-belief understanding in infants. Trends in cognitive sciences, 14(3), 110–118. doi:10.1016/j.tics.2009.12.006 Bratman, M. (1992). Shared Cooperative Activity. Philosophical Review, 101(2), 327–341. Bratman, M. (1993). Shared Intention. Ethics, 104(1), 97–113. Bratman, M. (2009). Shared Agency. In Philosophy of the Social Sciences: Philosophical Theory and Scientific Practice. Cambridge University Press. Brownell, C. A. (2011). Early Developments in Joint Action. Review of philosophy and psychology, 2(2), 193–211. doi:10.1007/s13164-011-0056-1 Butterfill, S. (2012). Joint Action and Development. The Philosophical Quarterly, 62(246), 23–47. doi:10.1111/j.1467-9213.2011.00005.x Carpenter, M. (2009). Just How Joint Is Joint Action in Infancy? Topics in Cognitive Science, 1(2), 380–392. doi:10.1111/j.1756-8765.2009.01026.x De Bruin, L. C., & Newen, A. (2012). An association account of false belief understanding. Cognition, 123(2), 240–259. doi:10.1016/j.cognition.2011.12.016 Grazzani, I., & Ornaghi, V. (2012). How do use and comprehension of mental-state language relate to theory of mind in middle childhood? Cognitive Development, 27(2), 99–111. doi:10.1016/j.cogdev.2012.03.002 Liszkowski, U., Carpenter, M., & Tomasello, M. (2008). Twelve-month-olds communicate helpfully and appropriately for knowledgeable and ignorant partners. Cognition, 108(3), 732–739. doi:10.1016/j.cognition.2008.06.013 Moll, H., & Tomasello, M. (2007). Cooperation and human cognition: the Vygotskian intelligence hypothesis. Philosophical Transactions of the Royal Society B: Biological Sciences, 362(1480), 639–648. doi:10.1098/rstb.2006.2000 Pacherie, E. (2011). Framing Joint Action. Review of Philosophy and Psychology, 2(2), 173–192. Rakoczy, H., Tomasello, M., & Striano, T. (2006). The role of experience and discourse in children’s developing understanding of pretend play actions. British Journal of Developmental Psychology, 24(2), 305–335. doi:10.1348/026151005X36001 Symons, D. K. (2004). Mental state discourse, theory of mind, and the internalization of self–other understanding. Developmental Review, 24(2), 159–188. doi:10.1016/j.dr.2004.03.001 Tollefsen, D. (2005). Let’s Pretend! Children and Joint Action. Philosophy of the Social Sciences, 35(1), 75–97. doi:10.1177/0048393104271925 Tomasello, M., Carpenter, M., Call, J., Behne, T., & Moll, H. (2005). Understanding and Sharing Intentions: The Origins of Cultural Cognition. Behavioral and Brain Sciences, 28(5), 675–691. Tomasello, M., & Haberl, K. (2003). Understanding attention: 12- and 18-month-olds know what is new for other persons. Developmental Psychology, 39(5), 906–912. doi:10.1037/0012-1649.39.5.906 Wellman, H. M., Cross, D., & Watson, J. (2001). Meta-Analysis of Theory-of-Mind Development: The Truth about False Belief. Child Development, 72(3), 655–684. doi:10.1111/1467-8624.00304