Reply from Jerome Ravetz
As usual I am nearly overwhelmed by these replies, and I only wish that I could respond to each of them.
Let me try to handle some issues that came up repeatedly.
First, we can find it very useful to look at the correspondence in today’s London Independent newspaper between Steve Connor and the eminent physicist Freeman Dyson (here described as an ‘heretic’), on http://www.independent.co.uk/environment/climate-change/letters-to-a-heretic-an-email-conversation-with-climate-change-sceptic-professor-freeman-dyson-2224912.html?action=Gallery.
Dyson makes a very basic point, that the uncertainties are just too great for any firm policy decision to be made. Connor, by contrast, presents a number of scientific claims, all of which he believes to be solid and factual. Then the argument shifts to more general issues, and Dyson eventually pulls out.
Now some people on this blog may believe that Connor is some paid hack or prostitute who is peddling alarmists’ lies; but it is also possible that he really believes what he is saying. For Dyson, it could be (and here I am mind-reading, on the basis of what I would do in similar circumstances) that he saw that short of taking a couple of crucial issues and digging ever deeper into the debates about them, he was on a path of rapidly diminishing returns. That left him looking like someone who didn’t want to argue, and so leaving the field to the expert.
For me, that is a reminder that before one engages in a debate one needs to be sure of one’s ground. And that requires an investment of personal resources, taking them from other commitments. That is one reason why I do not engage in detailed discussions of scientific issues, but try to do my best with the issues of procedure. Of course, that can seem cowardice to some, but so be it.
Now there is the fundamental point of the sort of science that ‘climate change’ is. The big policy question is whether there is enough strength of evidence for AGW to justify the huge investments that would be required to do something about it. That is not a simple hypothesis to be decided by an experimental test. There are the ‘error-costs’ to be considered, where those of erroneous action or inaction would be very large. The decision is made even more complex by the fact that the remedies for CO2 that have been implemented so far are themselves highly controversial. Therefore, although the issues of: the policies to adopt; the strength of the scientific evidence for AGW; the behaviour of the AGW scientists – are all connected, they are distinct. People can hold a variety of positions on each of these issues, and they may have been changing their views on each of them. This is why I tried to argue that the situation is best not seen as one of goodies and baddies.
As to Post-Normal Science, I was recently reminded of an example that was very important in setting me on the path. Suppose we have an ‘environmental toxicant’, on which there is anecdotal evidence of harm, leading to a political campaign for its banning. Such evidence is not sufficient, and so scientific studies were undertaken. But these used test animals, over short timespans with high doses. On the basis of those results a dose-response curve was obtained, which in principle should lead regulators to define a ‘safe limit’. But those results were from a temporary acute dose, while the policy problem related to a chronic low dose. And then (and here’s the kicker) it was realised that in extrapolating from the lab situation to the field situation, the method of extrapolation was more important in defining the dose-response relations in the field than was the lab data itself.
So Science was producing, not a Fact but an artefact. That for me became a good example for the PNS mantram. For that sort of problem, there was a classic paper about policy for environmental toxicants’, by A.S. Whittemore, published in Risk Analysis in 1983. In any real situation of that sort, there will be plenty of experts on both sides of the value-conflicted policy process, who really believe that their data is conclusive (children with unusual symptoms on the one side, lab rats with LD50 doses on the other). In practice, there is a negotiation, where scientific evidence is introduced and contested as one element of the situation.
Reflecting on that sort of problem in relation to PNS, I came up with point about science now needing to relate to Quality rather than to Truth. That was rather neat, but also a cause of much trouble, for which I issue another apology. My critics on this issue (notably Willis) have provided me with much food for thought. I don’t resolve these things in a hurry, and there are still others in the pipeline, but here’s how I see it now. In a recent post, Willis gave his definition of truth, which is a very good one relating to scientific practice. But for him (and I agree) it means that a scientific truth is a statement that might actually be false. From a scientific point of view, that’s good common sense; to imagine that any particular scientific statement ranks with 2 + 2 = 4 is the most arrant dogmatism. However, that means that our idea of scientific truth is quite different from the ordinary one, where there is an absolute distinction between ‘true’ and ‘false’.
One way out of that problem is to believe that scientific truth is indeed absolute. On that there is the classic pronouncement by Galileo: “The conclusions of natural science are true and necessary, and the judgement of man has nothing to do with them.” This is echoed in practice by generations of teachers, who present the facts dogmatically and discourage any questioning. I was one of those who reacted against that authoritarian style of scientific indoctrination. Now, if one is doing routine puzzle-solving research, the issue of truth is not too pressing; one can know that somehow, somewhere, one’s results will be superceded in one way or another; but that’s all over the horizon. But in cases of urgent policy-related research like the toxicant example I mentioned above, to believe that one’s anecdotes or one’s lab-rats give the truth about the danger of the toxicant, is mistaken and inappropriate. For when such conflicting results are negotiated, what comes into play is their quality.
Having said all that, I now see clearly that Truth cannot be jettisoned so casually. I have two paths to a rescue. One is to make the issue personal; to say ‘this is the truth as I see it’, or ‘to the best of my knowledge it is true’, or ‘I am being truthful’. This allows one to acknowledge a possible error; what counts here is one’s competence and integrity. And of course this has been at the core of the Climategate dispute, arising out of the CRU emails, the question of the correctness of their results is tangled with the morality of their behaviour.
The other path brings in broader considerations. Our inherited cultural teaching mentions a number of absolutes, including The Good, The True, The Just, The Holy and The Beautiful. These provide the moral compass for our behaviour. Now we know that these are goals and not states of being. Those who believe that they have achieved them are actually in a perilous state, for they are subject to delusion and hypocrisy. Perhaps someone reading this will take offense, for they might be sure that they have achieved perfection in one of these, and (for example) be perfectly good or just. If so I apologise, on a personal basis, for giving offense.
For the rest of us, life is a struggle, always imperfect, to achieve those of the goals that define who we want to be. Now, if we say that science is mainly devoted to achieving the goal of truth, and that every real scientist realises that as much as possible in his or her imperfect practice, then we have something that works. All this may be obvious or banal to those who never had this problem; I am inflicting it on you all because I have been exposed to so many scientists who sincerely believed that Galileo’s words settled the issue forever.
As usual, this is going on and on. Let me deal with my Quaker friend. I never said that I am a Quaker, only that I attended Swarthmore. I have looked up the site for Quaker Business Practice, and find it very inspiring. Although I do not express my beliefs in the same way, I find there an approach that expresses my own commitments. In particular, there are some recommendations about practice, which I shall quote (for brevity, out of context).
*A Sense of the Meeting is only achieved when those participating respect and care for one another. It requires a humble and loving spirit, imputing purity of motive to all participants and offering our highest selves in return. We seek to create a safe space for sharing.
*We value process over product, action or outcome. We respect each other’s thoughts, feelings and insights more than expedient action.
And, just as a reminder of the issues I discussed above,
*Friends would not claim to have perfected this process, or that we always practice it with complete faithfulness.
It might seem all too idealistic, to expect such attitudes to survive outside a rather special (and small) group of dedicated people. But I recall that some have seen the life of science as an approximation to just that. In the interwar period there were two distinguished scientists who involved themselves in public affairs, one on the far Left and the other on the Right; they were J.D. Bernal and Michael Polanyi respectively. Their disagreements were urgent and profound. But they both loved science, and saw in it an example, imperfect but still real, of the ideal community of selfless sharing in which they believed. I should say that the motivation for my first book was to see whether, and in what ways, that essential idealism of science could be preserved under the ‘industrialised’ conditions of the postwar period. What happened in that quest, and after, is quite another question; but the commitment is still there.
And finally. What I said about Sarah Palin was not about her but about me. It is one of the complexities of life that issues are there in a variety of dimensions, not all of our choosing. I have friends in the critical-environmental movement who are really grieved at my defection; and as I have seen all too clearly, there are those in the anti-AGW camp who think very ill of me. So be it.
Thanks for bearing with me through all this, and thanks for stimulating me to a better understanding.