1. A computer program product, comprising: a non-transitory computer readable storage medium having program instructions embodied therewith, the program instructions readable by a processing circuit to cause the processing circuit to perform a method of facilitating a meeting of a group of participants, the method comprising: generating a data structure that represents a graph of words from speeches of the participants, as the words are received from the participants in electronic text form, wherein the graph includes a plurality of nodes and a plurality of edges, each node representing a word or a phrase said by a participant, and each edge representing a temporal precedence of utterance of the words; analyzing the graph of words to determine cognitive states of each of the participants respectively; determining a combined cognitive state for a subgroup of participants, wherein the combined cognitive state for the subgroup of participants represents a composite of the cognitive states of each respective participant of the subgroup, wherein determining the combined cognitive state comprises: retrieving, from an information repository, weights associated with respective participants of the subgroup of participants, wherein a weight assigned to each respective participant is based on a prior social network post of the each respective participant that is automatically retrieved and analyzed from an external information repository; and combining the cognitive states of the participants of the subgroup according to the corresponding weights of the participants of the subgroup; and informing, electronically, at least one of the participants about the combined cognitive state of the subgroup of participants, wherein the informing comprises displaying the combined cognitive state on an electronic display.