Every so often I get sucked back into reading 'climate change' arguments. I bought Gareth Morgan's book as a patriotic duty – when an intelligent New Zealander pays for me to get an objective account then I owe it to him to see what he thought.

Since then I've left the stuff pretty much alone. Unless you're prepared to learn the science, you'll usually be in the hands of the talented and persuasive folk whose articles you last read.

I'm sure there is a human influence on climate. I do not know whether it outweighs natural cycles. I do not know whether getting warmer is good or bad overall, though I rather like the world I know so I start with a preference against change. I do know that the richer we are the more scope we have to adopt technologies that minimise damage to the physical world without sacrificing things that no democratic leader will be able to persuade us to sacrifice.

The risks may justify sensible preventative measures. They are almost certain not to be the hair shirt policies on which the world is planning to waste $trillions. Our ETS  is possibly one of those, though it may be the least we can do under political constraints without incurring the geopolitical costs of simply repudiating the obligations we signed up to many years ago.

A friend recently sucked me back into this by sending what she considered to be a challenging web article. I could not open it. Instead of taking that as a piece of good luck, foolishly I sent her a short optimistic piece by Matt Ridley from the Huffington Post. She responded with a Monbiot article. I've followed up on some of the latter's links.  Then I came across a 2 July Telegraph piece by Bjorn Lomborg.

Cathy and I spent a happy couple of days escorting Bjorn Lomborg to dive the Poor Knights and white water raft during a New Zealand visit. I prefer his company to that of the gloomy Green party priests who deal with their personal demons by trying to inflict the modern equivalent of ecclesiastical rule on us all.

Lomborg believes that climate change is a risk. He urges precautions. But he wants them to be intelligent.

His Telegraph article reports on Copenhagen Consensus Centre research into the costs and benefits of current European energy policy:

"Using the conventional estimate that one ton of carbon dioxide is likely to cause about $7 (£4.50) of damage, [researcher Richard Tol] found that the total benefit of the EU policy was just £5.7 billion. In other words, every euro spent is likely to generate just three cents' worth of benefits. [Lomborg's] research shows that by the end of this century, the EU's approach will reduce temperature rises by approximately 0.05C – almost too small to measure."

That's my fill of climate change argument for this year. I do not want any more:

a)  because none of it can be conclusive to a layperson;

b)  because the physical world I know best is so much better and healthier than when I was young so my personal experience fits better with Ridley's optimism;

c)  because I prefer optimism to pessimism. It is less wearing. Optimists are more fun to have around. When there is uncertainty about which is most merited, why not choose the one that is more pleasant?

d)  because there is nothing I can do in my personal use of resources that will make a blind bit of difference to the physical world even if the pessimists are right, whereas

e)  there is much that I can do about the social world that might have some practical influence for good as well as equip us with more wealth with which to play our part in improving the physical world when the time comes.