Abstract: A business or social networking method described herein enables mobile device users to meet one another, on a permission basis. Whether a given pair of mobile device users are introduced depends on whether a server determines they are in intellectual or “cognitive” proximity, which is typically a function of one or more factors. Individuals who match to a given degree or threshold are said to be in intellectual proximity. When given mobile devices users are within physical proximity of one another during an overlapping time window, the server determines whether the users are also within a given intellectual proximity. If so, and if both users have opted to receive new introductions, the server issues a mutual collaboration opportunity message to the users to determine whether they desire an introduction. If the mobile device users agree to be introduced, the server establishes a direct private messaging session between them.