Knuth’s art of Recovering from errors
IREALLy ENjOyED Donald E.
Knuth reminiscing in Edward
Feigenbaum’s interview with
him (“The ‘Art’ of Being Donald Knuth,” July 2008). Who
else would have moved to Stanford
University to slow down?
Knuth’s self-effacing modesty notwithstanding, I would like to challenge
anyone to examine the literature preceding Knuth’s contribution to algorithms and compiler theory. There
was good work, but it was Knuth who
set the field on its feet. I’m now looking forward to learning how he “solves
the problem of typesetting” (see Aug.
2008). I personally made the mistake
of using Microsoft Word for my Ph.D.
thesis (completed 1996). More recently, I decided that the topic—efficient
object-oriented programming for
of interest again due to the rise of multicore computers and reformatted it as
a book. What a nightmare. I promised
myself I’d use La TeX for every Ph.D. I
ever write again.
Philip machanick, taringa, Australia
Dependable Design and the
consequences of failure
Leah Hoffman’s news article “In
Search of Dependable Design” (July
2008) was a good overview of some
of the issues affecting software and
system reliability, explaining how
system dependability might be improved through good engineering
practice. This is similar to a subject
I covered in Technology Review (Apr.
1987) on software reliability.
However, Hoffman did not adequately discuss the theoretical limits
that add to the risk of real-time, interactive applications. Peter Wegner’s
Communications article “Why Interaction Is
More Powerful Than Algorithms” (May
1997) pointed out that interaction systems are not only difficult to verify but
also formally incomplete, impossible
to verify. Where the risk of system failure cannot be further reduced due to
such limits, effort must be directed in-
stead at reducing the consequences of
Ron enfield, Cherry hill, nJ
technology supports, Doesn’t
supplant the social compact
In “Information Accountability”
(June 2008), Daniel J. Weitzner et al.
so exaggerated the good points they
made that they created a false dichotomy between computing technologies (such as encryption) and societal
conventions and laws, summing up
in the article’s final sentence: “
Technology will better support freedom
by relying on these social compacts
than by seeking to supplant them.”
They were wrong. Technology does
not seek to supplant social compacts
but indeed seeks to add to them, legitimately.
alex simonelis, montreal
Proud to Be a member
My usual routine on finding
Communications in my mailbox is to spend
a few minutes flipping through the
pages, then throw it on top of a pile
of other unread magazines ready for
recycling. However, the new cover
typography (July 2008) immediately
caught my eye. The title font was crisp
and simple, recalling the all-caps,
squarish characters of a teletype from
the 1950s, very post-modern.
Flipping through the pages, I was
struck first by the new design—clean
and cool yet serious, information-dense, with narrow margins. And with
articles on model checking, XML,
transactional memory, and more, I actually wanted to read it. Beginning with
the interview with Emerson, Clarke,
and Sifakis, I then read the article on
the history of IT in India and the article
on quantum computing before I came
to the Editor’s Letter describing the
I had somehow missed that
Communications was being overhauled.
All I can say is: The editors, staff, and
contributors have done an amazing
job. I’ve never really spent time thinking about ACM as an organization,
but having a professional journal of
this quality makes me proud to be a
henry Kautz, rochester, n Y
Congratulations on the first issue of
the new Communications (July 2008).
The lineup of all-star authors (some
of my favorite people in the field) and
the relevant topics were amazing. It’s
wonderful to see computing’s flagship
journal return to such a high level of
quality. The blend of code, program-ming-model, language, architecture,
education, legal, and business topics
represented an inspirational cross-section of the industry.
The issue reminded me how much
fun it is to be a computer scientist.
Reading it from cover to cover made
me even more proud to sign my
David chaiken, menlo park, CA
Due to a copy-editing error, a comma
was added to the name of one of the
authors of the Research Highlights
paper “Wake Up and Smell the Coffee: Evaluation Methodology for the
21st Century” (Aug. 2008). Our apologies to J. Eliot B. Moss.
Communications welcomes your opinion. To submit a
Letter to the Editor, please limit your comments to 500
words or less and send to email@example.com.