Once you get your zealots excited and talking, social network theory and the subsequent effects of contagion suggest that they can in turn influence 10s, 100s and 1000s of like-minded social citizens.

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Without walking over his IP, his six principles of fomenting contagion nicely packaged in a handy acronym, STEPPS, are Social currency, Triggers, Emotion, Public, Practical value and Stories.

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While fears that the Suez Canal might close due to the social uprising in Egypt helped push up costs, it was the fear of contagion that shook markets more strongly.

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