 Another suggestion is that a participant intends not the entirety of the activity, but only his or her part in it. Such an intention is more modest in that it does not purport to settle what other people do. An account of shared activity in terms of such intentions (e.g. Tuomela &amp; Miller 1998, Kutz 2000) does not entail the authority or control over others that would be difficult to reconcile with the activity being shared. But this modest intention involves a commitment only to one’s part in our J-ing and doesn’t seem to account for a participatory commitment to our J-ing as a whole. To see why not, consider the case of walking together from Gilbert 1990. We might describe my part as walking at a certain pace. But intending to do that is entirely compatible with undermining my partner’s contribution, for example by tripping him. Suppose instead that we avail ourselves of some robust conception of part, so that each participant intends to do his part in shared activity, as such. This would appear to rule out attempts to undermine a partner’s contribution. But what exactly is this intention? It seems to presuppose an understanding of the concept of shared activity, which is the notion we’re trying to  elucidate.[31]