REINVENTING THE WHEEL
A personal report
By Mark Perakh
Posted August 17, 2004
The reason for writing this essay is the appearance of a
paper by William Dembski wherein he
introduces a measure of information he has dubbed "variational information"
(the initial version of that paper has disappeared from the web but is
available from the those who received Dembski's initial mailing, including me; modified version is at http://www.iscid.org/boards/ubb-get_topic-f-10-t-000086.html).
Dembski emailed the initial version of that paper to a number of both his
critics and supporters (I was one of the critics who received that email). In a
remark accompanying the text of the paper, Dembski, among other things, wrote
that he would appreciate critical comments, in particular because he would not
like to "reinvent the wheel."
As it
happened, Dembski indeed did just that – his "variational information" turned
out to be a quantity known for over forty years as a particular case of Rènyi
divergence (see http://www.cscs.umich.edu/~crshalizi/weblog/234.html).
In fact,
there is nothing unusual in "reinventing the wheel." It has happened many times
and even accomplished scientists are not guaranteed to be immune to such
occurrences. Modern science and mathematics comprise such immense amount of
material that rediscovering something long known happens now and then.
The
situation is, though, not quite harmless if he who reinvents the wheel has been
acclaimed as a great expert in a given field but in fact is shown to be unaware
of significant developments in that field (as is the case with Dembski who is
not only highly praised by his cohorts for his supposed breakthroughs, but also
does not shy away from a self-aggrandizing claims (see, for example, www.talkreason.org/articles/revolution.cfm
).
Sometimes
the existence of preceding results rediscovered by a researcher comes to light
before his alleged discovery has been published. In such cases the "rediscovery"
has little or no consequences besides a lesson to the researcher himself to do
better next time. If, though, the announcement about the supposedly discovered wheel
has been published, it may cause a considerable embarrassment for the
re-discoverer.
If a
scientist reinvents the wheel, the overall effect upon his reputation is
largely determined by his behavior after his flop comes to light. If the
researcher promptly admits his error, apologizes for it and does not insist
that his work still is an important contribution to science, the embarrassment
is usually mild, short-living, and easily forgiven. If, though, the offender
tries to downplay his error and to wriggle out of the predicament by inventing
casuistic arguments supposedly justifying his flop (as Dembski seems to be
doing so far) it can only worsen his status even if his admirers continue
fervently defend him.
All this reminded
me how I once reinvented the wheel and what came out of it.
It happened in 1952. I was at that time a docent (which is
the Soviet equivalent of the Associated Professor rank in the USA) at an
institute in Dushanbe, the capital of Tajikistan (now an independent country
but at that time part of the USSR)
One day my
colleague, Yuri Nikolaevich Petrov, who was head of the department of machine
repair technologies, approached me with a request. He and his assistants were
conducting experiments wherein they studied ways to repair worn-out steel
machine parts by reinstating their original dimensions through
electrodeposition of iron layers on their surface. Petrov showed me a steel plate upon which a layer of iron was electrodeposited.
The plate, which was flat before the deposition of iron, now was bent.
Obviously, the deposited layer of iron formed in a state of strong stress thus
bending the substrate upon which it was deposited. Petrov asked me whether or
not I could suggest a method for calculation of stress in the deposited layer
on the basis of a measurement of its deformation.
At that
time I was engaged in other projects. Tajikistan, like Japan, is a country
where earthquakes happen for breakfast, lunch, and dinner. I was largely
immersed in some problems of seismometry.
Still, I promised Petrov to think about his problem whenever I would
have a window in my schedule.
The Party
and the government took care of providing the necessary window: in a few days
after my conversation with Petrov, the studies at the institute were
temporarily suspended and all the students and instructors sent to the
agriculture regions to pick cotton; the rain season was approaching and the
cotton fields, as was usual for an economy ruled by five-year plans, remained unharvested.
While
students picked cotton, we, the instructors, supervised them – and it would
last for several weeks.
One day,
during a lunch break, I found a semblance of shadow under the branches of a cotton
plant, lay down and opened a notepad. By the end of the break I had a formula
derived for calculation of stress in deposited metallic layers. Satisfied, I ceased thinking of Petrov's
problem. When we returned to the city, I went to Petrov and handed over my
formula on a piece of paper torn from my notepad. I thought the matter was
closed. I was wrong.
In a few
weeks Petrov reappeared in my office. He displayed a bunch of graphs
representing the stress in deposits as function of various parameters. He
wanted to write a paper for a technical journal about his experimental data,
and since he used the formula I derived for him, he thought I might be
interested to be his co-author.
At that
time I had a very few papers published (although I don't remember the exact
count, it was certainly no more than around a dozen). The prospect of having a
paper published was luring. However, I immediately realized that before writing
a paper I needed to go back to my formula which was derived very hurriedly in a
cotton field. I wanted to verify the formula's validity and to check whether or
not a similar calculation of stress was conducted by somebody previously. At
that time we had no PCs, no Google, no internet. A search of literature was a
tedious and lengthy endeavor. I went to the library of the Academy of Sciences
and solicited help from professional librarians versed in the required
literature searches. In a few weeks I
had laid my hands on a paper that had a direct bearing on my problem.
The paper
in question was published in the Proceedings of Royal Society in 1909, that is
over forty years earlier. Its author was Gerald Stoney of the Cambridge University,
the man credited with inventing the term "electron." (G. G. Stoney, Proc. Roy.
Soc., A82, 1909: 172). Stoney had derived a formula for calculation of stress
in deposited layers. To my astonishment my formula, derived under a bush on a
cotton field, turned out to be an exact replica of Stoney's formula known for
over forty years. I happened to reinvent the wheel.
I told
Petrov that I could not be his co-author in the planned paper – he should
simply refer to Stoney.
My feelings
were ambivalent. On the one hand, I naturally felt a faint disappointment
because of having reinvented the wheel. On the other hand I (also naturally for
a beginning scientist) felt some satisfaction – I had effortlessly derived a
formula which was deemed worth a publication in the Proceedings of the Royal
Society!
I could hardly envision at that time that many years later (in
1978) the Royal Society would award me a prize for my research and invite me to
come to England as their guest.
What
happened, though, I became hooked on stress calculation. I started thinking
about this problem and soon came to the conclusion that Stoney's formula, which
I inadvertently rediscovered forty years later, was in fact wrong! Stoney's (and my) error was understandable, while its discovery
required a rather deep analysis of the problem. Under the cotton bush,
hurriedly deriving the formula, I simply repeated Stoney's error of forty years
earlier.
Thus
started my journey into the fascinating field of stress. In 1966 I published (in Russian) a monograph
on stress in films which in 1970 was translated into English and published in
the USA by the National Bureau of Standards (now renamed NIST – National
Institute of Standards and Technology). When this book came to attention of
some IBM scientists, they arranged for my invitation as a visiting scientist to
the IBM Research Center in Yorktown Height, NY. I came to the US and have been
here ever since.
That is
what came of my reinventing the (defective) wheel - a derivation of a long
known and in fact erroneous formula under a bush in a cotton field.
So
reinventing the wheel may not necessarily be a bad thing, even if the wheel is
defective – what counts is how the wheel's re-inventor behaves when the facts
come to light.
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