  In recent years, a new class of models for multi-agent epistemic logic has
emerged, based on simplicial complexes. Since then, many variants of these
simplicial models have been investigated, giving rise to different logics and
axiomatizations.
  In this paper, we present a further generalization, where a group of agents
may distinguish two worlds, even though each individual agent in the group is
unable to distinguish them. For that purpose, we generalize beyond simplicial
complexes and consider instead simplicial sets. By doing so, we define a new
semantics for epistemic logic with distributed knowledge. As it turns out,
these models are the geometric counterpart of a generalization of Kripke
models, called "pseudo-models". We identify various interesting sub-classes of
these models, encompassing all previously studied variants of simplicial
models; and give a sound and complete axiomatization for each of them.
