Ridley’s first and most consistent argument is that specialization (the ability of one person or organization to do one thing while another does another thing) and exchange (the ability to trade the products of those two things) set humans apart from other animals and enable growth / prosperity because the whole us greater than the sum of the parts. He provides a great deal of evidence for this position and his argument is quite compelling.
His second argument is that time and again humans have found ways to overcome dire threats to their well-being, hence the cause for the optimism in the title. He also argues that government regulation by and large interferes with economic growth (through specialization and exchange) and inhibits human innovation (which we need to overcome all of those dire threats).
These arguments are cogent and, if the book had stopped here, I would have given it a higher rating.
Ridley goes a step further, though, and effectively argues that, because humans have a long tradition of overcoming threats, we shouldn’t concern ourselves with said threats. I take umbrage with this kind of fatalism and counter-argue that concerning ourselves with said threats is exactly HOW we keep overcoming them – but them I’m an entrepreneur while he is a [minor] British noble heir so he and I may have very different ideas about self efficacy and agency.
The author also contradicts himself frequently when convenient for his arguments. For example, in one section, he demonstrates how foolhardy it would have been to extrapolate trends from pre-industrial-revolution economies into the 20th century. The industrial revolution changed the rules of the game dramatically such that some things that had previously been linear became exponential.
Yet, when arguing against the seriousness of some current threats – like climate change – he extrapolates trends from long ago to support his point. Not only is this fallacious and hypocritical, it seems willfully ignorant in his particular case: Ridley was Chairman of the first English bank to go insolvent in 150 years at the outset of the 2007 financial crisis. If anyone should understand the folly of making decisions on anachronistic data, it should be he!
As another example, he cites multiple reasons (high cost, inconsistency of production, etc.) why green energy technologies are inferior to fossil fuels (Ridley has been accused of a conflict of interest in Parliament due to his investments in the coal industry.). However, he spends chapters describing how humans invariably overcome exactly those types of challenges. Indeed it is instructive to read this 2010 book through the hindsight of 2017 as we have seen innovations drive down the costs of green energy technologies substantially. He should listen to his own advice and be optimistic!
Ridley’s worst offense in this book is a liberal use of the straw man fallacy. He portrays all environmentalists, for example, as being anti-growth and anti-technology. He also frequently uses impractical biofuels as a green energy punching bag as if they are the only alternative to fossil fuels. His data are quite selective and he introduces false dichotomies, e.g. between combating climate change and combating malaria.
This book started out well and then really fell apart for me. It’s almost as if Ridley had a good concept for the first few chapters but then was compelled by his publisher to stretch it into a longer book. In doing so, he introduced many logical fallacies and made proclamations that haven’t held up even just a few years after publication. That said, it was an interesting read – especially the beginning – but the content might be better suited for a TED talk than a 450-page book.