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"Permaculture is a philosophy or design discipline that seems to mean a lot of different things to different people - from a fairly purist focus on 'permanent agriculture', as the term was originally coined, to a"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/sustainable-product-design/permaculture-principles-clearing-up-the-ambiguity.html>