The May/June 2011 story “The Rare-Earth Crisis” unfortunately opens with a common fallacy: “Today’s electric cars and wind turbines rely on a few elements that are mined almost entirely in China. Demand for these materials may soon exceed supply” (emphasis added). Demand and supply are connected by prices, and if supply changes, prices change and generate a new equilibrium. At no point does demand “exceed” supply. When prices rise, substitutes or new sources of supply—or new technologies—emerge. This is especially true of rare earths, because they aren’t really “rare”—just costly and environmentally dirty to produce. The real advantage the Chinese have had is that they have been willing to tolerate pollution from rare-earth mining, something they might be increasingly unwilling to do. Yes, the Chinese can create and exploit short-term disruption, but in the longer term, they will only encourage greater production or substitution elsewhere.
Louis S. Thompson
Materials shortages are not a new phenomenon, but the rare-earth crisis described by Katherine Bourzac portends a change in their nature. In the 1970s, the best permanent magnets were made of an alloy of samarium and cobalt, with the cobalt coming almost entirely from mines in Zaire. When Zaire became politically unstable, cobalt supplies dwindled and prices rose, spurring the research that produced the neodymium-iron-boron magnets that we use in today’s high-tech motors and generators. Neodymium-iron-boron outperforms samarium-cobalt in most respects, so this shortage had a positive outcome for magnet technology. We can only wish for such outcomes today. Technologies have grown more complex, and devices today can use 50 or 60 elements, rather than a handful. The rare earths are notable for the specificity of their properties, the interconnectedness of their sources, the rapid growth of industries that depend on them, and China’s near monopoly on their supply. They are essential components of best-in-class magnets, phosphors, lasers, fiber optics, catalysts, abrasives, and more. Never before has technology been so vulnerable to critical shortages. We need to predict supply crises better than we do today, and ensure that we have the ability to develop alternatives whenever shortages occur.
Director, Ames Laboratory
As biomedical researchers, we read with interest the story on privacy by Simson L. Garfinkel (“How to Stop the Snoopers,” March/April 2011). The article implied that data mining is a phenomenon promulgated by predatory corporations and designed primarily to encroach on people’s personal lives and privacy. Among other things, data mining provides substantial benefits in genomic research by helping to sift through millions of data points to find actionable correlations between genes and diseases. Data mining is overall a socially valuable endeavor. The difficult part is finding a way to employ large-scale aggregate uses of data mining while protecting the privacy of the individual.
Dov Greenbaum and Mark Gerstein
New Haven, Connecticut
It’s a joy to read about Space Exploration Technologies (SpaceX), a private company that collaborates with NASA in an effort to carry humans to space (“Rocket Road,” May/June 2011). Private companies can do a great deal, but much more than NASA’s occasional help is needed to pursue the old dream of space colonization. The infrastructure for such an endeavor would require international coöperation and resources from all space nations. Otherwise, we will remain glued to Earth. Or am I daydreaming well past the point at which space colonization has turned into a pipe dream?
Jaron Lanier states that IBM’s “alchemical agenda” presented science in a “sloppy” way by pitting Watson, complete with its pleasant voice and canned banter, against human masters on Jeopardy! (“It’s Not a Game,” May/June 2011). Despite their justifiable pride, members of the Watson team have been uniformly sober and realistic. Jeopardy! is a fine way for a team working on deep question-answering systems to display their progress, draw the public into a teachable moment, and give it a glimpse of the scientific challenges involved and of experiences the future might hold with automated online help desks and other technologies. Lanier is in a long line of critics who keep moving back the goalposts: every time a minor milestone is reached, they claim, “But that isn’t real AI.” There’s nothing mystical about Watson—just good problem identification, good science, good execution, and good presentation.
David G. Stork
Portola Valley, California
I was expecting the author to do a comparison between Watson’s use of the discredited, 20th-century symbolic approach to AI and more promising, current AI research. Instead, I read a whiny essay about how IBM’s Jeopardy! stunt is attracting enemies of science who are skeptical of evolution and climate change. This is truly lame. The public has the right and duty to be skeptical of science.
I found your editorial and review on WikiLeaks (“Is WikiLeaks a Good Thing?” and “Transparency and Secrets,” March/April 2011) thought-provoking. I think of a saying in psychology: You’re only as sick as your secrets. The words “privacy” and “secrecy” are often used interchangeably, but they are actually distinct concepts. Privacy is a matter of mutual respect, while secrecy is more conspiratorial: keeping something hidden in the anticipation that others will try to discover it. The very proliferation of leaks means there are far too many secrets being kept. In a free society, official secrets should be at an absolute minimum. How can people make informed choices when information is being hidden from them? I’m glad that WikiLeaks exists, and I hope it’s a Hydra that never runs out of heads.
North Vancouver, British Columbia
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