The Collective Brain

Matt Ridley has recently spoken at TED and at Google on his new book entitled "The Rational Optimist".
In his book, Ridley describes a species named homo economicus.  This species transcends biological evolution with the introduction of exchange.  Exchange (or simply known as trade) is unique to humans and predates farming.  Ridley argues that exchange is to technological progress as sex is to biological evolution.

With the advent of exchange, humans technology for the first time advanced faster than human biological evolution. Ridley uses the example of the Australian hand axe that changed very little over one million years.  The humans who used this tool evolved genetically faster than the design of the tool evolved (over a period of 30,000 human generations).  Ridley argues that neither tool making nor language can explain the remarkable ascent of the human species.   Neanderthal man (H. neanderthalensis) is now believed to have had language and is believed to have had a brain bigger than that of homo sapiens but yet, remained at a subsistence level of existence until it went extinct.

What allowed humans to flourish and rise above mere subsistence survival, in contrast to other species such as H. neanderthalensis, was the advent of trade and exchange.  Obsidian knives dating back 40,000 years are found hundreds of miles from their source in Ethiopia. This is evidence that human populations were employing trade long before developing agriculture.  In the 1800's David Ricardo described the power of trade.  How it multiplies human effort and knowledge.  In 1958, Leonard E. Reed wrote "I Pencil" about how technologies can be created by the "collective brain".  The knowledge behind these technologies is not held by any one person but rather in the collective brain of society.  Ridley says this collective intelligence is the result of "ideas having sex".  Our collective intelligence is now growing expedentially as the internet allows ideas to be shared and combined in new ways as never before.

Ridley borrows heavily from many thinkers in his book.  Adam Smith and David Ricardo on specialization.  Jane Jacobs on the history of trade and rise of cities.  Leonard E. Reed on collective knowledge and Paul Romer on the sharing of ideas.  Ridley readily admits that he borrows liberally from past thinkers but adds that this is the very point of his book... how ideas and knowledge can be shared and exchanged, thus creating new ideas and fostering increasing intelligence and technology.  In this respect, Ridley has succeeded in writing a very convincing and inspiring book.

http://www.youtube.com/watch?v=OLHh9E5ilZ4