Building on earlier studies which indicate we have four levels of relationships: acquaintances, casual friends, friends and good/best friends, Hall conducted several studies arriving at these conclusions - it took about 50 hours of interaction to move from acquaintance to casual friend, about 90 hours to move from casual friend to friend, and more than 200 hours to qualify as a best friend. Those who never got beyond being acquaintances usually had spent no more than 30 hours together—the equivalent perhaps of being in the same class a few hours a week, but not seeing each other outside of the classroom.
The conclusions Hall draws from this work are straightforward, but important. “You have to invest," time and energy in order to have a deeper and authentic friendship.
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