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[퍼온글] Is science useful ? - by Isaac Asimov

2003.02.25 15:57

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It is the fate of the scientist to face the constant demand that he
show his learning to have some "practical use." Yet it may not be of
any interest to him to have such a "practical use" exist; he may feel
that the delight of learning, of understanding, of probing the universe,
is its own reward. In that case, he might even allow himself the indul-
gence of contempt for anyone who asks more.

There is a famous story of a student who (around 370 B.C.) asked
the Greek philosopher Plato: of what use were the elaborate and ab-
stract theorems he was being taught ? Plato at once ordered a slave to
give the student a small coin that he might not think he had gained
knowledge for nothing, then had him dismissed from the school.

The student need not have asked and Plato need not have scorned.
Who would today doubt that mathematics has its use ? Mathematical
theorems, which seem unbearably refined and remote from anything a
sensible man can have any interest in, turn out to be absolutely neces-
sary to such highly essential parts of our modern life as, for instance,
the telephone network that knits the world together.

This story of Plato, famous for two thousand years, has not made
matters plainer to most people. Unless the application of a new discov-
ery is clear and present, most are dubious of its value. A story about
the English scientist Michael Faraday illustrate the point.

In his time, Faraday was a enormously popular lecturer, as well as
a physicist and chemist of the first rank. In one of his lectures in the
1840's, he illustrate the peculiar behavior of a magnet in connection
with a spiral coil of wire which was connected to a galvanometer that
would record the presence of an electric current. There was no current
in the wire to begin with, but when the magnet was thrust into the
hollow center of the spiral coil, the needle of the galvanometer moved
to one side of the scale, showing that a current was flowing. when the
magnet was withdrawn from the coil, the needle flipped in the other
direction, showing that the current was now flowing the other way.
When the magnet was held motionless in any position within the coil,
there was no current at all, and the needle was motionless.

At the conclusion of the lecture, one member of the audience ap-
proached Faraday and said, "Mr. Faraday, the behavior of the magnet
and the coil of wire was interesting, but of what possible use can it
be?" Faraday answered poliyrly, "Sir, of what use is a newborn baby?"

It was the precisely the phenomenon whose use was questioned so pe-
remptorily by one of the audience that Faraday employed to develop
the electric generator, which, for the first time, made it pos-
sible to build the electrified technology that surrounds us today and
without which life, in modern sense, is inconceivable. Faraday's
demonstration was a newborn baby that grew into a giant.

Even the shrewdest of men cannot always judge what is useful and
what is not. There never was a man so ingeniously pratical in judging
the useful as Thomas Alva Edison, surely the greatest inventor who
ever lived, and we can take him as our example.

In 1868, he patented his first invention. It was a device to record
votes mechanically. By using it, congressmen could press a button and
all their votes would be recorded and totaled instantly. There was no
question that the invention worked: it remained only to sell it. A Con-
gressman whom Edison consulted, however, told him, with mingled
amusement and horror, that there wasn't a chance of the invention
being accepted, however unfailingly it might work. A slow vote, it
seemed, was sometimes a political necessity. Some congressmen might
have their opinions changed in the course of a slow vote, whereas a
quick vote might, in a moment of emotion, commit the Congress to
something undesirable.

Edison, chagrined, learned his lesson. After that, he decided never
to invent anything unless he was sure it would be needed and wanted
and not merely because it worked.

He stuck to that. Before he died, he had obtained nearly 1300
patents - 300 of them over a four-year stretch, or one every five days,
on the average. Always he was guided by his notion of the sueful and
the practical. On October 21, 1879, he produced the first practical
electric light, perhaps the most astonishing of all his inventions. (We
need only sit by candlelight for a while during a power breakdown to
discover how much we accept and take for granted the electric light.)

In succeeding years, Edison labored to imporve the electric light
before breaking. As was useful with him, he tried everything he could
think of. One of his hit-or-miss efforts was to seal a metal wire into
the evacuated electric light bulb, near the filament but not touching it.
The two were separated by a small gap of vacuum.

Edison then turned on the electric current to see if te presence of
a metal wire would somehow preserve the life of the glowing filament.
It didn't, and he abandoned the approach. however, he could not help
notcing that an electric current seemed to flow from the filament to
the wire across that vacuum gap.

Nothing in Edison's vast practical knowledge of electricity ex-
plained that phenomenon, and all Edison could do was to observe it,
write it up in his notebooks, and in 1884 (being Edison), patent it. The
phenomenon was called the "Edison effect," and it was the inventor's
only discovery in pure science. Edison could see no use for it. He
therefore pursued the matter no further and let it go, while4 he contin-
ued the chase for what he considered the useful and practical.

In the 1880's and 1890's, however, scientists who pursued "useless"
knowledge for its own sake discovered that subatomic particles (even-
tually called "electrons") existed, and that electric current was accom-
panied bya flow of electrons. The Edison effect was the result of the
ability of electrons, under certain conditions, to travel unimpeded
through a vacuum.

In 1904, the Elglish electrical engineer John Anbrose Fleming
(who had worked in Edison's London office in the 1880's in connec-
tion with the developing electric-light industry) made use of the Edison
effect and of the new understanding that the electron theory had
brought. He devised an evacuated glass bulb with a filament and wire
which would let current pass thorugh in one direction but not in the
other. The result was a "current rectifier."

In 1906, the American inventor Lee De Forest made a further elab-
oration of Fleming's device, introducing a metal plate that enabled it
to amplify electric current as well as to rectify it. The result is called
a "radio tube," because only such a device could handle an electric
current with sufficient rapidity and delicacy to make the radio a prac-
tical instrument for receiving and transmitting sound carried by the
fluctuating amplitude of radio waves. In fact, the radio tube made all
of our modern electronic equipment possible - including television.

The Edison effect, then, which the practical Edison shrugged off as
interesting bu useless, turned out to have more astonishing results that
any of his practical devices. Actually, the problem isn't to show that
pure science can be useful. It is a much more difficult problem to find
some branch of science that isn't useful. Between 1900 and 1930, for
instance, theoretical physics underwent a revolution. The theory of rel-
ativity and the development of quantum mechnics led to a new and
more subtle understanding og the basic laws of the universe and of the
behavior of the inner components fo teh atom.

None of it seemed to have the slightest use for mankind, and the
scientists involved - a brilliant group of young men - apprantly had
found an ivory tower for themselves that nothing could disturb. Those
who survived into later decades looked back on that happy time of
abstraction and impracticality as a Garden of Eden out of which they
had been evicted. For our of that abstract work there unexpectedly
came the nuclear bomb, and a wordl that now lives in terror of a
possible war that could destory mankind in a day.

.....(추후에 연속......HYS. 타이핑하기 넘 힘들다...)
* administrator님에 의해서 게시물 이동되었습니다 (2007-03-06 13:40)