As our social structures grew more complex, we developed more elaborate ways to identify members of our tribes such as manners of speech, clothing, body piercings, ID cards and so forth.

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Millennials love to find unique ways to express themselves one only need note the difference in the number of tattoos and body piercings between generations to validate this observation so novelty, marks that are fresh and exciting, and the unexpected quickly signal cool.

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At this time of year, walking from one to the other will probably involve negotiating four jugglers, two unicyclists, a retro-clad maiden doing light operatics and a local who's trying make a quid from her world-record number of body-piercings.

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