In the multi-agent setting, it is relevant to model group dynamics of agents, and logic has proved to be an excellent tool. We have proposed in previous work an epistemic logic that allows one to formalize the new beliefs formed or removed by a group of agents, where several groups can co-exist and where an agent can pass from one group to another. A novelty introduced in this paper is that an agent can be lent by a (willing) group to another one in case of need. Another distinguished feature we introduce in this paper is time and temporal instants/intervals to express the time periods in which agents’ beliefs hold.
