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Science and Trust: Are They Compatible?
Volume 2, Number 17: 1 September 1999

In beginning their 5 August 1999 Nature commentary on 'How to restore public trust in science," Greenpeace's Benny Haerlin and Doug Parr state that "the relationship between the scientific community and the general public has never been worse in living memory."  They cite as the reason for this sad state of affairs the ugly fallout from debates over such things as the safety of genetically modified crops, CFCs and the ozone hole, health and environmental assessments of potentially toxic substances and, of course, carbon dioxide and global warming.  The perceived lack of candor by many participants in these protracted controversies, they note, has "led to the development of the 'precautionary principle' by legislators around the world to shift the burden of proof from protectors to perpetrators."

In spite of their noble intentions to outline a course of action to remedy this situation, Haerlin and Parr only add to the problems that have led to the public's distrust of science by classifying participants in scientific debates as either "protectors" or "perpetrators."  Within the context of the debate over CO2 and global warming, for example, they would probably classify representatives of industries that emit CO2 (and, by association, the scientists that are sometimes funded by them) as perpetrators and those who lobby for CO2 emission restrictions (and the scientists sometimes funded by them) as protectors.

What's wrong with these words, you ask?  Simply the fact that their very definitions convey implications of not only right and wrong, but of good and evil.  What a way to stack the decks and invite unneeded controversy, petty squabbling and all of the other distasteful things (such as retaliatory name-calling) that cause the public to throw up their hands in disgust at attempts to resolve issues that require the services of science.  Indeed, if we know from the beginning that the people on one side of an issue are the perpetrators (of something really sinister, no doubt) and that those on the other side are the protectors (of all that is good and right, of course), why, we don't even need a debate.  (Hmmm. We're beginning to see their point!)

To their and Greenpeace's credit (we do like to give it where it's due), however, Haerlin and Parr state that "sound science is about the best possible way to answer a given question."  They also correctly note that "there are no clear answers to many of the 'big picture' scientific questions asked by the public."  And they rightly suggest that with respect to certain questions surrounding these issues, "honest scientists will frequently have to answer: 'We don't know', 'We cannot know' or 'These are our guesses'."

It is interesting to consider these answers as applied to the question "Will a continuation of the ongoing rise in the air's CO2 concentration lead to detrimental global warming?"  Although scientists and laymen alike have various opinions or "guesses" on this subject, few could honestly say "We know."  More would probably say "We can know," but there would likely be considerable disagreement over just how soon such knowledge might be obtained.

In the meantime, as we strive for greater understanding, perceived threats to earth's environmental integrity continue to cry out for answers, especially when they have risen so high in the public consciousness as to have a life of their own.  The most recent response to this dilemma, as noted by Haerlin and Parr, is the emergent popularity of the "precautionary principle," which suggests that precautionary measures be taken to avert the negative consequences (loss of agricultural productivity, for example) of some phenomenon (global warming) that may be produced by another phenomenon (rising atmospheric CO2 concentrations) that are thought to be due to human activities (the burning of fossil fuels).  More often than not, however, the application of this principle is anything but straightforward.

In the case in question, global warming has positive effects as well as negative ones.  It can extend the growing season over much of the earth, for example, and thereby open up lands for agriculture that are currently too cold for crops to grow to maturity and produce harvestable yields.  It can also enhance the hydrologic cycle to produce more rain in many areas.  And the aerial fertilization effect of the atmospheric CO2 enrichment that is believed to drive global warming actually does enhance plant productivity, while its anti-transpiration effect actually does reduce plant water requirements, thereby greatly improving plant water use efficiency, as has been convincingly demonstrated in literally thousands of laboratory and field experiments.

Clearly, the precautionary principle does not render decision-making any easier.  One still must know the truth, or a good approximation of it, to apply the principle rationally (see our Vol. 2, No. 9 Editorial Where is Truth?).  In addition, certain issues transcend science, as is also noted by Haerlin and Parr, who state that sometimes "arbitration between different answers is beyond scientific competence."  Unfortunately, the presumed transcendence is often nothing more than politics (see our Vol. 2, No. 12 Editorial Is It Science or Politics?).  And when science and politics come together, the debate frequently reverts to name-calling, although more elegant terms are typically used to obscure this tactic: terms such as mainstream and consensus, for example, as opposed to the more raucous perpetrators and protectors of Haerlin and Parr's essay (see our Vol. 2, No. 15 Editorial What Consensus?.

When all is said and done, therefore, we are left with but one real resource to attempt to answer the sample question we address in this editorial - Will a continuation of the ongoing rise in the air's CO2 concentration lead to detrimental global warming? - as well as all other questions that possess an element requiring the services of science; and that tool, as noted by Haerlin and Parr, is sound science.  That is why, from the very beginning of our website, we have taken as our motto the title of our Vol. 1, No. 2 Editorial: Show Us the Science.

Yes, sound science is what we look for; and sound science is what we try to report.  But one must never be too trusting about what is proffered as such; for this identical criterion of claiming to rely solely on sound science is what everyone on all sides of an issue likes to claim as his own and special virtue.  What it really comes down to, then, is you. You are responsible for evaluating what anyone claims.

So, do you trust yourself?  We do (trust ourselves, that is); but only because we work at it.  And you must too.  Scientists are no more virtuous or infallible than any other segment of society; and if a scientist wants your trust, let him or her earn it.

Dr. Craig D. Idso
Dr. Keith E. Idso
Vice President

Haerlin, B. and Parr, D.  1999.  How to restore public trust in science.  Nature 400: 499.