After reading the story of dan cziczo’s research on clouds (“Getting Ahead in the Clouds,” March/April 2013), I wonder what Professor Cziczo thinks about the recent work done by Georgia Tech researchers and published in Proceedings of the National Academy of Sciences. The researchers found that droplets form just as quickly around pollution particles as they do around other particles. Did this team use a significantly different method of studying cloud formation?
Professor Cziczo responds:
The study by researchers at georgia Tech surprisingly found that warm clouds—clouds that are composed of water droplets with no ice present—appear to form under the same conditions regardless of their geographic location and how much they were influenced by pollution.
Our research is different in two ways.
First, most of the work we’re doing in my lab at MIT focuses on clouds that contain ice. Whereas water droplets in warm clouds form on most of the particles present in the atmosphere, ice crystals are known to form on particularly effective particles called ice nuclei. Ice nuclei are incredibly rare—they are thought to represent less than 1 in 10,000 of the particles in the atmosphere. For this reason, human activities can have a very large influence on ice cloud formation—changes to less than 0.01 percent of the particles in the atmosphere can have an influence on these clouds.
Second, when we study ice and droplet formation, we actually collect the particles that form droplets and analyze them on a particle-by-particle basis. Our results show that the particles that form droplets most effectively—that is to say, at the lowest humidity—are different from those that form droplets less readily. This is a very different study from the one done by Georgia Tech, and the two sets of results aren’t necessarily in conflict. Our results suggest that some particles are more effective than others at forming droplets. Their work suggests that regardless of where you go—at least within the regions they sampled—particles aren’t that different at forming droplets.
The Story of a Study of the Mind
Given the conservative nature of evolution, Rebecca Saxe’s statement that “we gain capabilities that have no parallels in the animal kingdom” seems illogical (“The Story of a Study of the Mind,” March/April 2013).
I believe Theory of Mind is not unique to humans, in fact.
Moreover, if any “unique” human brain > behavior processes are valuable, and not epiphenomenal, why don’t other animals have them and why did they take so long to evolve?
Human exceptionalism seems a quaint notion at best.
Elmer Rich III
It has been said children are born with all the knowledge in the universe. I have always taken that to mean they have what Shunryu Suzuki, the Zen monk and teacher, referred to as the “beginner’s mind.” As he put it, “In the beginner’s mind there are many possibilities; in the expert’s mind there are few.” Saxe’s results, as well as her explanation, seem to show we are, indeed, born with a blank slate, open to the numerous possibilities extant in our world. Only as we grow do we unlearn many—if not most—of these possibilities as we specialize and develop our “expert minds,” at least with respect to social interaction. Very interesting research.
Simi Valley, California
Ethics at MIT
As a student of zen for decades, i read with interest your article on the formation of the secular Dalai Lama Center for Ethics and Transformative Values at MIT (“Bringing Ethics into Education,” March/April 2013). While the story states that “the Venerable Tenzin Priyadarashi was stunned by the lack of ethics training in the U.S. education system,” he seems to have missed the ethics of rigor, openness, relentless self-criticism, honesty, and reliance on evidence so manifest at MIT. This ethical foundation of science and medicine has led to a spectacular reduction in human suffering in its few short centuries.
By the way, it is as inappropriate for an MIT publication to refer to “His Holiness the Dalai Lama” as it would be to refer to “His Holiness the Pope.”
David G. Stork ’76
Portola Valley, California
Join the Discussion, or Contact Us
WriteMIT News, One Main Street, 13th Floor, Cambridge, MA 02142
Please include your address, telephone number, and e-mail address. Letters and comments may be edited for both clarity and length.
Couldn't make it to EmTech Next to meet experts in AI, Robotics and the Economy?Go behind the scenes and check out our video