Zarrella's Hierarchy of Contagiousness: The Science, Design, and Engineering of Contagious Ideas
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Zarrella's Hierarchy of Contagiousness: The Science, Design, and Engineering of Contagious Ideas

SIX PRINCIPLES OF CONTAGIOUSNESS
Social Currency
We share things that make us look good
Triggers
Top of mind, tip of tongue
Emotion
When we care, we share
Public
Built to show, built to grow
Practical Value
News you can use
Stories
Information travels under the guise of idle chatter