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I live in Bedford, England. Having retired from teaching; I am now a research student at the University of Bedfordshire researching into Threshold Concepts in the context of A-level Physics. I love reading! I enjoy in particular fiction (mostly great and classic fiction although I also enjoy whodunnits), biography, history and smart thinking. I have also recently become a keen playgoer to London Fringe Theatre. I enjoy mostly classics and I read the playscripts and add those to the blog. I am a member of Bedford Writers' Circle. See their website here: http://bedford-writers.co.uk/ Follow me on twitter: @daja57

Thursday, 30 July 2015

"How nature works" by Per Bak

This book is subtitled The Science of Self-Organized Criticality and explains the new discipline of Complexity Theory, the the process making it distinct from Chaos Theory.

Per Bak is a critical (pun not intended) researcher in this field, having been one of the first to devise the famous sandpile experiments in which grains of sand are dropped one by one onto a pile of sand and the size of the subsequent avalanches recorded. From here to theoretical models of ridiculous simplicity modelled on desk top computers which provide results which closely match phenomena as diverse as:

  • The distribution of earthquake size
  • The distributions of extinctions within the fossil record
  • Learning
  • Economics
  • Traffic jams

The suggestion is that many systems evolve into a position of 'Self Organized Criticality'. At this point small external events will trigger adjustments of the system, some of which will be unnoticeably small and some of which will be enormous. Key insights are:

  • That you do not need to postulate an external trigger for a catastrophe, systems such as the world's ecosystem or a the world's stock markets are always on the edge of catastrophe anyway so that a very small trigger can create a massive landslide (but normally doesn't, of course)
  • That these systems are very large so that you need to consider the entire ecosystem of the world (which might include the atmosphere - life creates oxygen - and the oceans and the landscape) or the entire geological system of the world (earthquakes and plate tectonics etc) or the economics systems of the world or an entire brain etc
  • That these systems may be hierarchical such that complex astrophysical systems give rise to complex geological systems which give rise to complex biological systems (eg life) which give rise to complex ecological systems etc etc.


This was a fascinating book, mostly very readable, which gives insight into this fascinating new science. A slight criticism is that the bibliography appears quite selective and some of the researchers mentioned in the text do not appear, making it difficult to access their original work.

July 2015; 198 pages

Other books covering this interesting topic include:



Other books not reviewed on this blog on this topic include:

  • The Wisdom of Crowds 
  • Tipping Point by Malcolm Gladwell about fads
  • Ubiquity which is brilliant about fractals and power laws
  • Critical mass by Philip Ball which is a brilliant explanation about phase changes


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