**Rational optimism** <<>>

Last week the centre-right think tank Policy Exchange hosted a [talk](http://www.policyexchange.org.uk/events/event.cgi?id=273 “”) by Matt Ridley about his new book The Rational Optimist. I was very pleased to attend on Sandbag’s behalf, not least because I have been a reader and admirer of Ridley’s work for some time.

In Ridley’s latest book, he attempts to identify the main engine of human progress. What was it, he asks, that launched our culturally static hominid ancestors on an accelerating trajectory of prosperity, longevity and innovation leading to the present? His answer: trade – the exchange of ideas, goods or services between non-kin.

An unapologetic modernist, Ridley, very convincingly demonstrates how the global present is better than even the very recent past thanks largely to the power of trade, and his work is a powerful antidote to the nostalgia too many hold for some pre-industrial or pre-consumerist golden age.

**Rational pessimism**

As a kind of sociobiologist of economic liberalism, Ridley is suspicious of the good governments can achieve by intervening in the market and suspicious of those issues or agitators which demand such intervention. This makes Ridley overly damning of those “pessimists” who predicted resource crunches along the way to our present prosperity and he singles out panic-mongers on overpopulation, carcinogenic chemicals, sperm depletion and acid rain for particular scorn. But sometimes, even by Ridley’s own admission, we only escaped those Malthusian crunches by the skin of our teeth, and sometimes – though Ridley is less inclined to admit it – we have the pessimists to thank. Some prophets only become “false prophets” because the world heeded their warnings and acted. Prophets of avoidable doom are rational optimists too! One such prophet Ridley does seem to grudgingly accept is the British chemist Sir William Crookes who in 1898 prophesied mass starvation if a way of synthesizing nitrogen fertilizer were not soon invented. Fortunately for us, the fertilizer was subsequently invented.

During his presentation Ridley’s showed various graphs showing positive trends for human welfare. One of these, which also opens chapter 9 of his book, shows how US emissions of 4 conventional air pollutants have decreased between 1980 and 2008. The trouble is, the majority of these reductions were achieved by government policy, with two of them (SO2 and N2O) directly brought to heel by – you guessed it – [the Acid Rain Program](http://en.wikipedia.org/wiki/Acid_Rain_Program “”)!

**Irrational pessimism**

Ridley’s resistance distrust of government interventionism makes him dispositionally sceptical of climate change, too. For a self-styled optimist he is irrationally pessimistic about the damage climate mitigation could do to global prosperity, suggesting in Chapter 10 of his book, that it risks bringing about a “steep decline in living standards”. This is an extreme exaggeration: taking Nicholas Stern’s worst expectations of the costs of mitigation, [Adair Turner](http://www.sd-commission.org.uk/file_download.php?target=/publications/downloads/Turner-EconomicsClimateChangeFeb07.pdf “”) calculated this would delay the doubling to trebling of the global economy expected in 2050 by roughly one year. This represents neither a steep decline, nor even a deceleration, but an almost imperceptibly gentler acceleration of global growth.

Contrary to either the climate alarmists or the mitigation alarmists, the economic outlook for the 21st century is very good indeed – we can expect massive growth moderately diminished by climate change or we can expect massive growth minutely diminished by our efforts to stop it. Given the negligible differences between either scenario, isn’t it better that we accept the delay which removes a permanent drag on human progress rather than the delay caused by accepting it?

**Irrational optimism**

Like Nigel Lawson, Ridley seems to apply a 100% discount rate to the future beyond 2100, when the more startling impacts of climate change are expected to manifest. For example, a [recent study](http://www.metoffice.gov.uk/climatechange/policymakers/policy/informing-mitigation.pdf “”) by the Hadley Centre finds that the lower end projections of a global temperature rise of 1.8 degrees Celsius this century are expected to cause Amazon dieback of 20-40% if sustained into the 22nd century. The two uppermost predictions of 3.4 and 4 degrees would see dieback of 80% or more. This has profound effects, not only on biodiversity, but also on global rainfall patterns and in increased greenhouse emissions.

He also has a remarkably sunny view of the resilience of coral reefs when the IPCC predicts [global extinctions of coral](http://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch4s4-4-11.html#table-4-1 “”) as they’re overgrown by algae at around 2 degrees of 21st century warming. His optimism also seems grossly misplaced concerning our capacity to “nudge the natural carbon cycle” into taking up anthropogenic emissions. While biochar and the like are promising interventions, overall anthropogenic global warming is “nudging” the carbon cycle in the opposite direction, weakening existing carbon sinks already and turning terrestrial ecosystem into a [net source](http://www.ipcc-wg2.gov/AR4/website/spm.pdf “”) of carbon emissions as in the Amazon example above.

**The optimist’s wager**

To extend a metaphor of the economist Julian Simon – to whom Ridley is in many ways an intellectual heir – if human progress is viewed as a running race, we can expect to get considerably faster over the century ahead, but we face a choice between a temporary hindrance (mitigation costs), or a chronic hindrance, caused by permanent and worsening damage to the running track (climate impacts). We can gamble that our acceleration will continue at such a pace that we can ignore the deterioration of the track forever, but such an unnecessary wager sounds less like optimism and more like recklessness.