Imagine a group of kids kicking a ball, evolving certain patterns of play, and, over time, shared skills and a shared practice. Imagine further that they jointly form intentions to meet regularly a narrative, a body of beliefs about how their group and their game came abou, and negotiate a set of rules for it, which is passed on in the oral tradition. Finally, imagine these rules are written down various kinds of functionaries are enforce them and organize various aspects of the sport, fixed procedures are put into place for electing these officials and for resolving disagreements within the organization, and so on.

This vignette is supposed to illustrate that there are different layers or levels of collective intentionality. These layers can roughly be distinguished as the pre-conceptual layer of joint attention, joint bodily action, shared emotions and corresponding dispositions; the conceptual layer of we-beliefs, we-intentions and other joint propositional attitudes and the documental layer of institutional reality. We want to discuss these issues at a workhop in Vienna from August 16-18, 2018.

Questions to be addressed include the following:

•Can these layers be distinguished in terms of the representational formats of the representational states and artefacts that are involved, as suggested above, or are there problems with such an approach?

•What other parameters might be helpful in distinguishing layers?

•Is the distinction between layers categorial or should we rather think in terms of a continuum?

•To what extent and in which way do higher level layers depend on lower level? For example, how do joint beliefs depend on joint attention episodes? How do do the rules of group depend on its practices??O or otherwise defective

•Is the distinction between layers helpful at all, or might it also be misleading or counterproductive in certain ways?

•What is the relation between layers and the phylogeny and ontogeny of human and animal minds?