

Wealth-production mechanisms: a followup - lisper
http://rondam.blogspot.com/2009/10/wealth-production-mechanisms-followup.html

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frig
Pedant:

6\. Extract natural resources from the earth or space.

with your 1, 2, and 3 could be seen as including all there is to say about
energy; there are many perils trying to classify things.

