Next, I will review and evaluate the case for cooperative hunting among one specific community of chimpanzees and compare it with collective hunting in other observation sites. In the next section, I will discuss the concept of common ground, both from a descriptive standpoint as a set of mutual assumptions about other agents and the action they are partaking in and from a participative standpoint, as the assumptions an individual formulates about what the other is aware of. Over time, it will become easier for agents to predict each other’s actions and understand their state of mind with the support of the mutually understood procedure of the practice itself. Specifically, I will propose that the consolidation of a shared practice over time can help the individuals participating anticipate how others will behave, due to the constraints dictated by the procedures of the shared practice for it to be efficient. In this essay, I will suggest that the consolidation of a shared practice can explain the passage from the (probably) low cognitive abilities of early hominids to the sophisticated capacities of modern human beings to understand the mental states of others in the course of a joint action. This problem stands in the way of explaining the evolution of cooperation in general ( Koren 2016) and especially the evolution of communication ( Geurts 2019a, 2019b), which is extremely important for human beings and incomparable to other animals’ when it comes to sophistication. Specifically, there is somewhat of an explanatory gap between our hominid ancestors’ (presumably) unsophisticated cognitive abilities and the complex capacity to represent others’ intentions of human beings. Tomasello’s account of cooperation, which requires collective intentionality, is unsatisfying because whereas it is safe to assume that cognitively mature humans are well capable of collective intentionality, it does not answer the question of the evolution of cooperation. Therefore, the absence of 1) a shared motivation to act with others for anything other than merely instrumental goals and 2) the mutual awareness among individuals that they are acting together would suggest that non-human primates do not engage in cooperative activities strictu sensu ( Carpenter and Call 2013). Furthermore, it would be unwise to assume that non-human primates are capable of something as cognitively complex as representing others’ intentions and of second-person engagement. Non-human primates are occasionally capable of cooperation, but for Tomasello they do not have the motivation to engage in cooperative abilities (they mostly do so in experimental conditions): on the contrary, non-human primates (especially chimpanzees) are much more competitive than cooperative. This second-person representation of others’ mental states is a complex cognitive ability that only human beings seem to have. This means that while carrying out a cooperative action, not only must the individuals be aware of the shared collective goal and of the state of affairs wherein the action takes place, but they also need to mentally represent the intentions of others. In his view, human beings are capable of performing complex cooperative activities thanks to having collective intentionality. Tomasello in particular (2014) argues that collective intentionality is a specifically human capacity, and that it constitutes an important divide between humans and other animals. This capacity is either understood as a specific mental state (a “we-intention”, as Searle (1995) puts it) or as a way to coordinate one’s own intentions with the intention of other people ( Bratman 1992, 2009). 2012 Tomasello 2014) share the belief that cooperation is enabled by collective intentionality, understood as the intention to perform an action φ knowing that other agents are taking part in φ. Joint action is generally considered to be made possible by advanced cognitive abilities that only humans have: Searle (1995), Bratman (1992, 2009) and Tomasello ( Fahy et al. Human beings engage in daily cooperation, from modest cases such as walking together to much more complex practices: human communication, exceptional in the animal kingdom for the use of language, is a form of coordinated action. Cooperation and joint action are pervasive in everyday life.