The unknown unknowns

As we know, there are known knowns. There are things we know we know. We also know there are known unknowns. That is to say, we know there are some things we do not know. But there are also unknown unknowns, the ones we don't know we don't know.

                         --Donald Rumsfeld
                           Former U. S. Secretary of Defense

It ain't what you don't know that gets you in trouble. It's what you know for sure that just ain't so.

                         --Mark Twain

We are frequently assailed with the notion that knowledge is doubling every n-years and that the interval between doublings is shrinking with each doubling. We are even told that knowledge will someday be increasing at a rate that is so fast it will represent a distinct break in human history. After this turning point, often referred to as the singularity, machines will be smarter than humans and launch human society into an unprecedented orgy of invention and progress.

An antidote to this kind of thinking is David Orr's, Ecological Literacy, a compilation of essays that remain as fresh and profound today as they were when they were published in 1992. While Orr would not deny the proliferation of knowledge, he posits an equal and opposite reaction. With each doubling of knowledge, we get a doubling of ignorance.

What does he mean? The example he cites is the discovery of CFCs (chlorofluorocarbons) in the 1930s. These substances turned out to be marvelous as refrigerants and spray-can propellants. They are nontoxic, noncorrosive, nonflammable and odorless. As we learned more about them, we found new uses in manufacturing and as cleaning solvents. Our knowledge was increasing. Also increasing was our ignorance of the consequences of using CFCs. Only in the early 1970s did researchers discover that CFCs, once discharged into the air, make their way into the upper atmosphere and destroy the ozone layer. In fact, a large hole opened in the ozone layer in the mid-1980s giving dramatic testimony to the effects of CFCs.

But the discovery of the mechanism behind the ozone hole might very well have come too late had it not been for a lone scientist who wondered what happened to CFCs after they entered the atmosphere. It is a only matter of great good fortune that F. Sherwood Rowland obtained a grant in 1973 to find the answer. There was, in fact, no systematic search underway into the side effects of CFCs, and those side effects could have easily eluded our notice. Our growing ignorance came very close to imperilling all plant and animal life on the planet.

Similarly, our ignorance about the dangers and intractable problems of nuclear waste grew up in tandem with our expanding knowledge and application of nuclear power. The problem of what to do with the waste remains unsolved.

Our understanding of species loss comes in at a trickle as species are annihilated by the thousands every year. In a conversation the other day with a friend who counts birds at our local nature center, he made a moral argument for biodiversity. Don't the other organisms on the Earth have a right to exist as much as we do?

Forget the moral argument, I responded. All you need to do is ask yourself (and others) whether it is wise to wipe out species at the current colossal rate when we haven't even discovered some of the species we are wiping out and when we don't know the effect of such a bloodbath on the future viability of the human race? What if, without knowing it, we are wiping out species that are essential to our very survival? Is it worth the risk to continue as we have?

Also discussed in Ecological Literacy is a rather revolting scheme proposed by researchers at the United States Department of Agriculture that would ostensibly increase the carrying capacity and sustainability of farmland through the use of perennials. Orr describes the plan as follows:

Farms would no longer grow wheat, tomatoes, or corn, but rather cellulose from perennials having the attributes of 'tulip poplar, kenaf and a nitrogen fixing symbiont.' Cellulose would then be converted into syrups and transported by tank car or slurry line to food factories near population centers where they would be reconstituted into steaks, french fries, and zucchini with 'aesthetically necessary secondary metabolites, e.g., flavor compounds and pigments' added. Yum.

Orr doubts that such a system could actually be sustainable. And if it did fail for technological, political or ecological reasons, who would be left who knows how to grow actual food? Our knowledge about food and farming would be declining as our knowledge about how to grow cellulosic substitutes expanded, all without any assurance that the new system could be maintained indefinitely.

For most of us it is an article of faith that knowledge is expanding very rapidly. And many of us know for sure that this is always and in every way a good thing. David Orr has his doubts:

The belief that we are currently undergoing an explosion of knowledge is a piece of highly misleading and self-serving hype. The fact is that some kinds of knowledge are growing while others are in decline. Among the losses are vast amounts of genetic information from the wanton destruction of biological diversity, due in no small part to knowledge put to destructive purposes. We are losing, as David Ehrenfeld has observed, whole sections of the university curriculum in areas such as taxonomy, systematics, and natural history. We are also losing the intimate and productive knowledge of our landscape....On balance, I think, we are becoming more ignorant because we are losing knowledge about how to inhabit our places on the planet sustainably....

Wisdom, Orr writes, is in part knowing the limits of our knowledge. Wisdom implies a level of humility which the human race has thus far failed to demonstrate. Wisdom means accepting that there will always be unknown unknowns and acting accordingly.