We develop a model of deliberation under heterogeneous beliefs and incomplete information, and use it to explore questions concerning the aggregation of distributed information and the consequences of social integration. We show that when priors are correlated, all private information is eventually aggregated and public beliefs are identical to those arising under observable priors. When priors are independently distributed, however, some private information is never revealed, and communication breaks down entirely in large groups. Interpreting integration in terms of the observability of priors, we show how increases in social integration lead to less divergent public beliefs on average. (JEL D82, D83, Z13)