Letters

Prompted by this article, I dialed up Amtrak and tried out the $4 million experiment. I was impressed: it had a very nice voice and recognized my speech appreciably well-even when I gave deliberately obscure answers, such as “I don’t think so” and “not hardly.” The conversation fell far short of casual, though, as the voice kept telling me what things were best to say, interrupting me, and stepping on my words. I’m glad this effort is making headway, but I’ll believe in the technology when I can tell my personal digital assistant to reschedule an appointment without taking it out of my pocket.

Keith Rowell
Atlanta, GA

Stem Cell Ethics

The responses of Geron president and CEO Thomas B. Okarma in “Cloning, Stem Cells, and Medicine’s Future” (TR June 2003) exemplify all that is wrong in the discussion about the use of stem cells in biomedical research. There is no sound scientific basis for research that is destructive to human embryos, natural or cloned. Okarma’s suggestion that only cloned embryonic stem cells will allow us to discover disease-causing genes denies a rich history of beneficial disease research with nonembryonic cells. Okarma’s statements take advantage of the hope of people who yearn so desperately for cures that they will overlook moral and ethical objections because they are told that the science is sound and the research will be effective.

James L. Sherley
Biological Engineering Division
MIT
Cambridge, MA

Okarma makes it sound like the end of the world if we can’t start using embryonic stem cells to develop cures for various diseases. Your interviewer rightly pointed out that there are other, morally unobjectionable, sources of stem cells. In fact, unlike embryonic cells, nonembryonic stem cells have already seen some remarkable early successes, which Okarma seems to have rejected. Moreover, even if donor embryos are “surplus,” it doesn’t mean they are any less human. Killing them for the sake of research cannot be justified.

Robert B. Austenfeld Jr.
Hiroshima, Japan

Detecting Deceit

The story about a newfangled lie detector (“The Deceit Detector,” TR June 2003) was very likely misguided. Relating any physiological reaction to lying by the human subject is questionable. That connection is fraught with error, misinterpretation, and ambiguous causes; that’s why psychophysiologists who have been doing research in the area for decades doubt if there is any identifiable physiological “signal” for deception. Despite this, physical scientists continue to propose new methods of measurement, hoping they will fix up the discredited premise of the lie detector machine. This is a classic case of physical scientists (among whom I count myself) ignoring the work of behavioral scientists, who have a great deal to say about deception detection. Our hallowed intelligence agencies have made mistake after mistake by assuming that these machines are incontrovertible.

Bernard R. Foy
Santa Fe, NM

Proving Humanity

Simson Garfinkel’s diatribe against “captchas,” where e-mail services test to see if you are a human before allowing you to sign up (“Excuse Me, Are You Human?” TR June 2003), misses one very important point: these services are free! If you agree with Garfinkel that these tests could become such a problem as to be “deeply offensive,” then I suggest you pay for your e-mail service and avoid the whole situation.

Jerry Dawson
Portland, OR

Corrections: While there is an MIT Electrical Engineering 6.270 class in which robots compete, Michael Schrage’s June 2003 column, “Amateur Innovation,” should have cited “MIT’s famed Mechanical Engineering 2.70 competition.”

A caption in the June “Visualize” article “Garbage into Oil” should have stated that the turkey-parts-and-water slurry is subjected to a pressure of 50 atmospheres.