We're all embedded in vast social networks of friends, family, co-workers and more. We hate to admit but we are all clustered in herds and groups and tribes. We "like" and "dislike", are passionate or dull, and maintain the illusion that we solely decide how we feel and what we do. 

Nicholas Christakis tracks how a wide variety of traits -- from happiness to obesity -- can spread from person to person, showing how your location in the network might impact your life in ways you don't even know. His work has inspired us here at SocialCaddy and we wanted to share this talk with you.