According to Robin Dunbar, researcher in neuroscience who has studied human relationships, 150 numbers have been reached. According to surveys, that speech seems to be the limit of meaningful human relations.

”The figure of 150 seems to represent the maximum number of individuals with whom we can have a genuinely social relationship, the kind of relationship that goes with knowing who they are and how they relate to us,” Dunbar has written. ”Putting it another way, it’s the number of people you would not feel embarrassed about joining uninvited for a drink if you happened to bump into them in a bar.”

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Source Bloomberg

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