lunes, 22 de septiembre de 2008

El Impacto del Espacio en la Sociedad

En julio pasado asistí en Monreal, Canadá, a la 37ava Asamblea
General del Comité para Ciencia Espacial (COSPAR). Aunque he
paticipado en otras muchas de estas asambleas, y he constatado la
diversidad de disciplinas que abarca esta organización, nunca como ahora me di
cuenta de que gran parte de los participantes de todo el mundo
pertenecen a disciplinas muy alejadas de la mía, como la
exobiología, la medicina espacial, la astronomía, los rayos
cósmicos, la planetolgía la meteorología, la ecología, la
oceanoloía, la geofísica y la geología. La
delegación mexicana fue numerosa pero prácticamente todos eramos
de la rama de la física espacial. Y más me impactó este hecho
después de escuchar varias pláticas interdisciplinarias que me
hicieron preguntarme por qué Mexico parece estar ausente de este evento
tan importante, en otras áreas del conocimiento. Quizá la Conferencia de Len Fisk como las pláticas sobre los satélites
que "miran" continuamente a la Tierra en diferentes longitudes de onda,
tienen un poco la culpa.
Tuve la suerte de recibir el texto de la conferencia Impacto del Espacio en la Sociedad, Conferencia conmemorativa en la Asamblea General del Comité para la
Ciencia Espacial (COSPAR) en Montreal, Canadá, el 14 de julio de
2008, con motivo del 50 aniversario del COSPAR, por L. A. Fisk
Universidad de Michigan, EUA.
Los invito a leerla porque es sumamente ilustrativa del papel que ha jugado la ciencia espacial en la ciencia y la tecnología no sólo en Estados Unidos sino a nivel mundial.
Román

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sábado, 13 de septiembre de 2008

¿Que tan Falseable es la Ciencia?

ANÁLISIS DE LOS ARTICULOS:
Unified Scaling Law for Earthquakes (Bak, P., 2002).
Interevent Time Distribution in Seismicity: A Theoretical Approach (Molchan, G., 2005).
Theory of Earthquake recurrence times (Saichev, A. and Sornette D., 2006).

Angel Figueroa Soto

Se ha estipulado que la ciencia es una prueba para poder confiar en determinados productos, teorías o afirmaciones; ¿Quien de nosotros no ha pensado que un producto o un artículo científico es mejor si esta “probado” o aprobado científicamente? Sin embargo la ciencia como invento para explicar lo observado en la naturaleza, no es una verdad absoluta. Al contrastar una teoría a la experimentación (falsear) puede llegar a colocarse como una ley o ser desechada.

Aquellas teorías que no son reproducibles total o parcialmente durante la experimentación, muestran de que están hechas, llegando a desenmascarar las omisiones o hipótesis que el investigador realizó para formularla. Como ejemplos tradicionales podemos encontrar los experimentos de Robert Millikan (1913) para mostrar que la carga del electrón esta cuantizada, o los experimentos de Fleischmann y Pons (1989) para demostrar la fusión en frío. En ambos casos la experimentación posterior permitió descubrir las omisiones o fraudes que los autores realizaron para publicar ciencia o ganar el premio Nobel.

Dejando atrás este tipo de hechos lamentables, que están en función del fenómeno “publica o muere”, considero de manera muy personal, que una teoría tiene una mayor aceptación si logra superar pruebas que atenten contra su validez. Como un ejemplo de esto, analicemos el caso de la búsqueda de leyes universales en sismología, mediante distribuciones de tiempo inter sísmicos.

El análisis de distribuciones de tiempo entre sismos consecutivos ha sido estudiado analizando distribuciones de densidad de probabilidad (Molchan, 2005) y ha sido motivo de desarrollos de leyes unificadas o universales (Bak P., et al., 2002)⁠.

Bak (2002) propone el descubrimiento de una ley de escalamiento unificada para tiempos entre sismos consecutivos, que no dependería del intervalo de tiempo. Mediante el uso de la teoría para procesos críticamente auto organizados, concluye que la estadística de réplicas que ocurren en minutos o días, se puede relacionar a la estadística de sismos separados por decenas de años. Esto tiene como implicación que no hay una escala de tiempo que juegue un papel importante en el proceso de generación de sismos.

Ante esta publicación (Molchan, 2005)⁠ hace un desarrollo a partir del aparente descubrimiento de Per Bak. Para esto utiliza procesos estadísticos de tipo estacionarios y demuestra que la ley de escalamiento unificada de Bak puede existir bajo condiciones no realistas de tasas de sismicidad homogéneas.

Tiempo después, (Saichev A. and Sornette, D., 2006) desarrollan una teoría matemática para falsar lo argumentado por Bak y Molchan. La principal conclusión de este ultimo trabajo es argumentar que las leyes de escalamiento universal de tiempo inter sismos no podría ser una ley universal, ya que no revelarían mas información que la que está implícita en las leyes conocidas en sismología: Gutenberg-Richter, Omori-Utsu.

Este proceso que va desde la publicación de la teoría y sus posteriores procesos para desmentirla, constituiría una verdadera forma de hacer ciencia. Es en este proceso donde se puede estar expuesto a practicas equivocadas o a interpretaciones y/o conclusiones incorrectas.

Si se pudiera estar mas abierto a la crítica constructiva, estas practicas de falsar una teoría no sería visto como una forma de “desmentir o validar una teoría”, sino como un proceso donde una teoría se ajusta mejor que otra a lo que percibimos.


Referencias

Bak, P. et al., 2002. Unified Scaling Law for Earthquakes. Physical Review Letters, 88(17), 178501.

Hainzl, S., Scherbaum, F. & Beauval, C., 2006. Estimating Background Activity Based on Interevent-Time Distribution. Bulletin of the Seismological Society of America, 96(1), 313-320.

Molchan, G., 2005. Interevent Time Distribution in Seismicity: A Theoretical Approach. Pure and Applied Geophysics, 162(6), 1135-1150.

Saichev, A. & Sornette, D., 2006. Theory of Earthquake Recurrence Times. physics/0606001. Available at: http://arxiv.org/abs/physics/0606001 [Accessed September 9, 2008].

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lunes, 8 de septiembre de 2008

¿Cuál es correcto "The Data is" o "The Data are"?

Un asunto que nos da problemas a muchos de los que necesitamos escribir en inglés para difundir nuestros resultados a la comunidad internacional es el uso de los nombres en plural que provienen del Latín. En esta contribución intentaremos abrir el tema con algunos de los casos más comunes incluyendo sugerencias tomadas de varias fuentes.

El problema del uso en Inglés de palabras en plural provenientes del Latín no es exclusivo a aquellos quienes su lengua materna no es el Inglés. Un rápido vistazo a internet nos lleva a encontrar algunas ligas de habla inglesa en donde se trata de exclarecer el asunto.
Tal es el caso de la palabra "data" que es el plural de "datum". En lo personal, siempre he tenido dudas de si es adecuado decir "The data was collected", en lugar de "The data were collected" porque me he topado con ambos usos en trabajos publicados.
El problema según muchos se reduce a que, como la palabra es plural, es necesario emplearla en la misma forma que otras palabras que denotan un conjunto, tal como "people". Por eso no diríamos "Those people is nice" sino "Those people are nice".

Sin embargo, esto nos causa mayores problemas a quienes hablamos una lengua romance porque el uso de las palabras es diferente. En Español es correcto decir "La gente es buena" y no decimos "La gente son buenas" (claro que esto último alternativamente se podría decir "Las personas son buenas"). Astutamente evitamos el problema de la palabra "datum" empleando nuestra forma de "dato y datos".
Hay varias opiniones de que el uso de "data" en Inglés se ha "americanizado" y denota un conjunto que puede ser empleado en singular. Un ejemplo de éste último caso lo conforma la palabra "agenda" que originalmente es plural (conjunto de acciones (cada una es un "agendum" por llevar a cabo) y que actualmente se emplea en el singular (nunca escuchamos: "the agenda of the day are...").

Según parece, entonces no es un error tan grave usar la palabra "data" como singular. Sin embargo, si queremos evitar problemas con los correctores de estilo de algunas revistas científicas, es mejor ceñirnos a decir " The data were collected...".

Algunas referencias
http://www.gi.alaska.edu/ScienceForum/ASF3/334.html
http://www.johntcullen.com/sharpwriter/content/data_is.htm
http://www.wfu.edu/biology/albatross/dataare.htm

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sábado, 6 de septiembre de 2008

Hallan gen clave para vacuna contra el sida


Washington, 4 de septiembre. El hallazgo de un gen que juega un papel clave en la producción de anticuerpos que neutralizan los retrovirus podría abrir el camino a una vacuna contra el sida, según prometedores trabajos divulgados el jueves en Estados Unidos.

Este hallazgo casual realizado en ratones podría también explicar por qué algunas personas expuestas al VIH (virus de inmunodeficiencia humana), causante del sida, nunca lo contraen, indicaron los autores del estudio, divulgado en la revista Science del 5 de septiembre.


El gen, denominado Apobec3, que existe también en los humanos y en la misma región cromosómica, controla la capacidad de los ratones de producir anticuerpos que neutralicen retrovirus, lo que les permite combatir infecciones con éxito.

Hombres y ratones

Los investigadores creen que este gen podría jugar el mismo papel en los humanos y neutralizar el retrovirus que causa el sida.

Esta hipótesis es alimentada por estudios anteriores, que muestran que las proteínas producidas por Apobec3 tienen propiedades anti-VIH y que la región del cromosoma en la que se encuentra el gen influye en la capacidad de ese virus para infectar el organismo.

“Este avance pone en evidencia un mecanismo genético potencial de producción de anticuerpos capaces de neutralizar el virus del sida, lo que es esencial para impedir la infección”, subrayó en un comunicado el doctor Anthony Fauci, director del Instituto nacional estadunidense de alergias y enfermedades infecciosas.

“Otras investigaciones sobre la función del gen Apobec3 en los humanos podrían conducir al hallazgo de medicamentos y vacunas contra el sida”, añadió.

Los anticuerpos son la clave para combatir con éxito infecciones virales, y la mayoría de las vacunas estimulan la producción de anticuerpos contra un virus en particular. Pero, pese a un cuarto de siglo de investigación y a la movilización de importantes recursos, la ciencia aún no ha podido poner a punto una vacuna eficaz contra el virus del sida, origen de una pandemia que ha causado más de 25 millones de muertes.

Publicado en: http://www.jornada.unam.mx/

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miércoles, 3 de septiembre de 2008

Sobre publicaciones, indices de productividad y la revisión por pares en el contexto de la evaluación de productividad

Este es la declaración del
ICSU (International Counsil for Science) committee on Freedom and Responsability in the conduct of Science
sobre las practicas de publicación, indices y el papel de la revisión por pares en la evaluación de la investigación.
Primero enlista los puntos de preocupación, habla sobre la importancia de la revisión por pares, y finalmente da recomendaciones que se debe tomar en cuenta para la evaluación de productividad en la investigación.


ICSU committee on Freedom and Responsibility in the conduct of Science° (CFRS)

Statement°° on publication practices and indices and the role of peer review in research assessment


Progress in science, and confidence in the scientific process, depends on the accuracy and reliability of the scientific literature. This in turn depends on the rigour of the manuscript review process. In addition to ensuring the quality of scientific publications, independent peer review is also a critical part of the evaluation process for both individual scientists and research institutes. The ICSU Committee for Freedom and Responsibility in the conduct of Science (CFRS) is concerned that some of the policies and practices currently being adopted by scientific institutions and journal publishers may inadvertently be undermining the integrity of the scientific literature. This is compounded by the uncritical use of publication metrics, as a replacement for independent peer-review, in evaluating scientific performance. By pointing out these concerns to ICSU Member organizations, it is hoped that they will take action to ensure the quality of the scientific record and promote a cautious and critical approach to the use of publication metrics in research assessment.

Issues of concern:

1. In making career appointments and awarding grants, the publication record of applicants, and in particular the number and supposed impact of publications, is often a main criterion. This inadvertently creates incentives for duplicate publications, split publications, publications of little value, and honorary authorship.

2. Journal impact factors give an indication of the average number of citations to be expected for a paper in a particular journal, but these numbers are easily misinterpreted. For example, they can be influenced by the ratio of reviews to primary papers. Citations for any individual paper may be much higher or lower than that expected from the impact factor.

3. While the number of citations can give an indication of the quality of a publication, this is not necessarily so. Truly novel and very important papers may well attract little attention for several years after their publication. A paper that is incorrect can generate multiple citations from papers that rebut it, and citation numbers can be inflated by self-citation. Citation numbers also tend to be greater for reviews than for primary papers.

4. The value attributed to publication and citation records can pressure scientists to publish too early, or exaggerate and over-interpret results. It can also, in extreme situations, promote scientific misconduct, in which results are fabricated, falsified or plagiarised.

5. As a result of the pressure to publish, a growing number of manuscripts are submitted to multiple journals before they are ultimately accepted. This increases the burden on reviewers, which ultimately diminishes the thoroughness of the review process. Multiple submissions and reviews of the same work can delay the communication of important results and it can be argued that multiplying the number of reviews rarely prevents the eventual publication of poor quality work.

6. Alternative means of publication in un-reviewed or non-expert reviewed electronic archives, on individual or institutional home pages or blogs, are becoming increasingly popular. While these media open-up new possibilities and enhance general accessibility to publications, they also increase the availability of less significant or possibly misleading information.

CFRS is concerned that current policies and practices may be having serious effects on the quality of scientific work in general, and increasing the burden on journal reviewers. Any unnecessary increase in the volume of scientific publications threatens a proper reviewing process, which is essential for maintaining standards of accuracy and integrity.

In addition to its role in scientific publishing, the Committee regards rigorous and unbiased peer review as being the most important mechanism for judging the quality of scientific work and scientific projects. Establishing and maintaining good peer review processes is in itself a challenge and it is recognised that there can be benefits in using quantitative measures and metrics as complements to this process. However, the apparent simplicity and attraction of such numerical indices should not conceal their potential for manipulation and misinterpretation and they should therefore only be used with considerable caution.

Because norms for publication number, authorship conventions, and citations differ from field to field, judgements and policy are often best made by peers with expertise in the same area. CFRS urges ICSU’s member organisations to stimulate discussion of scientific evaluation criteria, career indicators and publication records, with the aim of promoting a system that can better serve science in general. Rather than learning to survive in a ‘publish or perish’ culture, young scientists should be encouraged and supported to produce high quality scientific communications that make a real contribution to scientific progress.
Questions for consideration, regarding the use of metrics in assessing research performance, include:

- In judging applications for grants and positions, what is the optimal balance between direct peer reviewing, including reading of relevant articles, and the use of quantitative measures based on publication records?

- In assessing publication records and performance, what weighting should be applied to publication number, h factors, journal impact factor, citation number, primary publication versus review?

- Noting that conventions vary considerably from one field to another, how much credit should be given to first authorship, last authorship, middle authorship, or corresponding authorship? In some fields the prevalence of ‘ghost authorship’ is also an issue of considerable concern°°°.

- What credit should be given for pre-prints and other electronic publications, whether they are peer reviewed or not? Should impact indices such as clicks, downloads, or links be taken into consideration?

- Should the number of publications that count towards grants or appointments be capped? For example, should only the best three publications per year be taken into consideration? Should scientists even be penalised for authorship on more than, say, 20 publications per year? [Such limits may seem counter-intuitive but would help to promote a culture in which all authors have genuinely contributed to the publications on which their names appear.]

- What weighting should be given to other quantitative measures of research output, such as patent applications, patents granted or patents licensed?

The Committee is aware that discussion of many of these issues is already well underway in some countries and some areas of science, but suggests that the debate is widened to the full international scientific community. By sharing options and strategies, it is hoped that the global science community can benefit from experiences of individual organisations.

*************************************************************************************
Addendum: Whilst this statement was being developed, the International Mathematical Union released the Citation Statistics report, which is a detailed critical analysis of the use of citation data for scientific evaluation. A main conclusion of this report is: While having a single number to judge quality is indeed simple, it can lead to a shallow under-standing of something as complicated as research. Numbers are not inherently superior to sound judgments.

See http://www.mathunion.org/Publications/Report/CitationStatistics
° See http://www.icsu.org/5_abouticsu/STRUCT_Comm_Poli.html#CFRS for the membership and terms of reference for CFRS.
°° This statement is the responsibility of the Committee on Freedom and Responsibility in the conduct of Science (CFRS) which is a policy committee of the International Council for Science (ICSU). It does not necessarily reflect the views of individual ICSU Member organizations.
°°° See, for example, Ross et al, JAMA 299, 1800-1812 (2008).

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lunes, 1 de septiembre de 2008

¿Por qué ciencias de la Tierra?

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La Tierra al desnudo. Proyecto OneGeology

¿Imaginas qué aspecto tendría nuestro planeta despojado de todas las plantas, los suelos, el agua y las estructuras hechas por el hombre? OneGeology, el mapa geólógico mundial más grande de la historia, nos lo muestra.

Especialistas en Ciencias de la Tierra y en Computación de 79 naciones, están trabajando juntos en un proyecto global llamado OneGeology (Una Geología) para producir el primer mapa geológico digital del mundo. Este proyecto hace lo mismo que Google con los mapas de la superficie terrestre, pero a nivel de las rocas bajo nuestros pies.

Según Ian Jackson, jefe de operaciones de la Sociedad Geológica Británica y coordinador del proyecto, "los mapas geológicos son herramientas esenciales para identificar recursos naturales como el agua, los hidrocarburos y minerales, así como para organizar planes para reducir riesgos geológicos tales como terremotos, erupciones de los volcanes o emisiones de radón”. Además, existen otros desafíos como “la subida del nivel del mar, la gestión de los residuos (nucleares o domésticos) y el almacenamiento de CO2, para los que el conocimiento de las rocas sobre las cuales todos vivimos se ha vuelto cada vez más importante”. “Compartir dicho conocimiento en un momento de cambio ambiental global es crucial”, concluye.

Las imágenes se hicieron públicas el dia 5 de Agosto durante el 33 Congreso Internacional de Geología, que entre el 5 y el 15 de agosto reúne en Oslo (Noruega) a 6.000 geocientificos de 117 países bajo el lema “geología para la sociedad”.

OneGeology (www.onegeology.org)

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"Surely You're Joking, Mr. Feynman!"

Este es un extracto del libro mencionado arriba que se refiere la educación científica que vio en Brasil cuando, hace muchos años, estuvo en Brasil de sabático. Lo pongo aquí porque me da la impresión de que en México no estamos muy lejos de lo que el Dr. Feynman critica. Creo que su lectura puede ser una garan lección no sólo para los estudiantes sino también para los profesores. Para los que quieran leer el libro completo, que es sumamente interesante, la liga es:
http://www.gorgorat.com/

In regard to education in Brazil, I had a very interesting experience.
I was teaching a group of students who would ultimately become teachers,
since at that time there were not many opportunities in Brazil for a highly
trained person in science. These students had already had many courses, and
this was to be their most advanced course in electricity and magnetism Maxwell's equations, and so on.

The university was located in various office buildings throughout the
city, and the course I taught met in a building which overlooked the bay.
I discovered a very strange phenomenon: I could ask a question, which
the students would answer immediately. But the next time I would ask the
question -- the same subject, and the same question, as far as I could tell
-- they couldn't answer it at all! For instance, one time I was talking
about polarized light, and I gave them all some strips of polaroid.
Polaroid passes only light whose electric vector is in a certain
direction, so I explained how you could tell which way the light is
polarized from whether the polaroid is dark or light.
We first took two strips of polaroid and rotated them until they let
the most light through. From doing that we could tell that the two strips
were now admitting light polarized in the same direction -- what passed
through one piece of polaroid could also pass through the other. But then I
asked them how one could tell the absolute direction of polarization, for a
single piece of polaroid.
They hadn't any idea.
I knew this took a certain amount of ingenuity, so I gave them a hint:
"Look at the light reflected from the bay outside."
Nobody said anything.
Then I said, "Have you ever heard of Brewster's Angle?"
"Yes, sir! Brewster's Angle is the angle at which light reflected from
a medium with an index of refraction is completely polarized."
"And which way is the light polarized when it's reflected?"
"The light is polarized perpendicular to the plane of reflection, sir."
Even now, I have to think about it; they knew it cold! They even knew the
tangent of the angle equals the index!
I said, "Well?"
Still nothing. They had just told me that light reflected from a medium
with an index, such as the bay outside, was polarized; they had even told me
which way it was polarized.
I said, "Look at the bay outside, through the polaroid. Now turn the
polaroid."
"Ooh, it's polarized!" they said.
After a lot of investigation, I finally figured out that the students
had memorized everything, but they didn't know what anything meant. When
they heard "light that is reflected from a medium with an index," they
didn't know that it meant a material such as water. They didn't know that
the "direction of the light" is the direction in which you see something
when you're looking at it, and so on. Everything was entirely memorized, yet
nothing had been translated into meaningful words. So if I asked, "What is
Brewster's Angle?" I'm going into the computer with the right keywords. But
if I say, "Look at the water," nothing happens -- they don't have anything
under "Look at the water"!
Later I attended a lecture at the engineering school. The lecture went
like this, translated into English: "Two bodies... are considered
equivalent... if equal torques... will produce... equal acceleration. Two
bodies, are considered equivalent, if equal torques, will produce equal
acceleration." The students were all sitting there taking dictation, and
when the professor repeated the sentence, they checked it to make sure they
wrote it down all right. Then they wrote down the next sentence, and on and
on. I was the only one who knew the professor was talking about objects with
the same moment of inertia, and it was hard to figure out.
I didn't see how they were going to learn anything from that. Here he
was talking about moments of inertia, but there was no discussion about how
hard it is to push a door open when you put heavy weights on the outside,
compared to when you put them near the hinge -- nothing!
After the lecture, I talked to a student: "You take all those notes --
what do you do with them?"
"Oh, we study them," he says. "We'll have an exam."
"What will the exam be like?"
"Very easy. I can tell you now one of the questions." He looks at his
notebook and says, " 'When are two bodies equivalent?' And the answer is,
'Two bodies are considered equivalent if equal torques will produce equal
acceleration.' " So, you see, they could pass the examinations, and "learn"
all this stuff, and not know anything at all, except what they had
memorized.
Then I went to an entrance exam for students coming into the
engineering school. It was an oral exam, and I was allowed to listen to it.
One of the students was absolutely super: He answered everything nifty! The
examiners asked him what diamagnetism was, and he answered it perfectly.
Then they asked, "When light comes at an angle through a sheet of material
with a certain thickness, and a certain index N, what happens to the light?"
"It comes out parallel to itself, sir -- displaced."
"And how much is it displaced?"
"I don't know, sir, but I can figure it out." So he figured it out. He
was very good. But I had, by this time, my suspicions.
After the exam I went up to this bright young man, and explained to him
that I was from the United States, and that I wanted to ask him some
questions that would not affect the result of his examination in any way.
The first question I ask is, "Can you give me some example of a diamagnetic
substance?"
"No."
Then I asked, "If this book was made of glass, and I was looking at
something on the table through it, what would happen to the image if I
tilted the glass?"
"It would be deflected, sir, by twice the angle that you've turned the
book."
I said, "You haven't got it mixed up with a mirror, have you?"
"No, sir!"
He had just told me in the examination that the light would be
displaced, parallel to itself, and therefore the image would move over to
one side, but would not be turned by any angle. He had even figured out how
much it would be displaced, but he didn't realize that a piece of glass is a
material with an index, and that his calculation had applied to my question.
I taught a course at the engineering school on mathematical methods in
physics, in which I tried to show how to solve problems by trial and error.
It's something that people don't usually learn, so I began with some simple
examples of arithmetic to illustrate the method. I was surprised that only
about eight out of the eighty or so students turned in the first assignment.
So I gave a strong lecture about having to actually try it, not just sit
back and watch me do it.
After the lecture some students came up to me in a little delegation,
and told me that I didn't understand the backgrounds that they have, that
they can study without doing the problems, that they have already learned
arithmetic, and that this stuff was beneath them.
So I kept going with the class, and no matter how complicated or
obviously advanced the work was becoming, they were never handing a damn
thing in. Of course I realized what it was: They couldn't do it!
One other thing I could never get them to do was to ask questions.
Finally, a student explained it to me: "If I ask you a question during the
lecture, afterwards everybody will be telling me, 'What are you wasting our
time for in the class? We're trying to learn something. And you're stopping
him by asking a question'."
It was a kind of one-upmanship, where nobody knows what's going on, and
they'd put the other one down as if they did know. They all fake that they
know, and if one student admits for a moment that something is confusing by
asking a question, the others take a high-handed attitude, acting as if it's
not confusing at all, telling him that he's wasting their time.
I explained how useful it was to work together, to discuss the
questions, to talk it over, but they wouldn't do that either, because they
would be losing face if they had to ask someone else. It was pitiful! All
the work they did, intelligent people, but they got themselves into this
funny state of mind, this strange kind of self-propagating "education" which
is meaningless, utterly meaningless!
At the end of the academic year, the students asked me to give a talk
about my experiences of teaching in Brazil. At the talk there would be not
only students, but professors and government officials, so I made them
promise that I could say whatever I wanted. They said, "Sure. Of course.
It's a free country."
So I came in, carrying the elementary physics textbook that they used
in the first year of college. They thought this book was especially good
because it had different kinds of typeface -- bold black for the most
important things to remember, lighter for less important things, and so on.
Right away somebody said, "You're not going to say anything bad about
the textbook, are you? The man who wrote it is here, and everybody thinks
it's a good textbook."
"You promised I could say whatever I wanted."
The lecture hall was full. I started out by defining science as an
understanding of the behavior of nature. Then I asked, "What is a good
reason for teaching science? Of course, no country can consider itself
civilized unless... yak, yak, yak." They were all sitting there nodding,
because I know that's the way they think.
Then I say, "That, of course, is absurd, because why should we feel we
have to keep up with another country? We have to do it for a good reason, a
sensible reason; not just because other countries do." Then I talked about
the utility of science, and its contribution to the improvement of the human
condition, and all that -- I really teased them a little bit.
Then I say, "The main purpose of my talk is to demonstrate to you that
no science is being taught in Brazil!"
I can see them stir, thinking, "What? No science? This is absolutely
crazy! We have all these classes."
So I tell them that one of the first things to strike me when I came to
Brazil was to see elementary school kids in bookstores, buying physics
books. There are so many kids learning physics in Brazil, beginning much
earlier than kids do in the United States, that it's amazing you don't find
many physicists in Brazil -- why is that? So many kids are working so hard,
and nothing comes of it.
Then I gave the analogy of a Greek scholar who loves the Greek
language, who knows that in his own country there aren't many children
studying Greek. But he comes to another country, where he is delighted to
find everybody studying Greek -- even the smaller kids in the elementary
schools. He goes to the examination of a student who is coming to get his
degree in Greek, and asks him, "What were Socrates' ideas on the
relationship between Truth and Beauty?" -- and the student can't answer.
Then he asks the student, "What did Socrates say to Plato in the Third
Symposium?" the student lights up and goes, "Brrrrrrrrr-up" -- he tells you
everything, word for word, that Socrates said, in beautiful Greek.
But what Socrates was talking about in the Third Symposium was the
relationship between Truth and Beauty!
What this Greek scholar discovers is, the students in another country
learn Greek by first learning to pronounce the letters, then the words, and
then sentences and paragraphs. They can recite, word for word, what Socrates
said, without realizing that those Greek words actually mean something. To
the student they are all artificial sounds. Nobody has ever translated them
into words the students can understand.
I said, "That's how it looks to me, when I see you teaching the kids
'science' here in Brazil." (Big blast, right?)
Then I held up the elementary physics textbook they were using. "There
are no experimental results mentioned anywhere in this book, except in one
place where there is a ball, rolling down an inclined plane, in which it
says how far the ball got after one second, two seconds, three seconds, and
so on. The numbers have 'errors' in them -- that is, if you look at them,
you think you're looking at experimental results, because the numbers are a
little above, or a little below, the theoretical values. The book even talks
about having to correct the experimental errors -- very fine. The trouble
is, when you calculate the value of the acceleration constant from these
values, you get the right answer. But a ball rolling down an inclined plane,
if it is actually done, has an inertia to get it to turn, and will, if you
do the experiment, produce five-sevenths of the right answer, because of the
extra energy needed to go into the rotation of the ball. Therefore this
single example of experimental 'results' is obtained from a fake experiment.
Nobody had rolled such a ball, or they would never have gotten those
results!
"I have discovered something else," I continued. "By flipping the pages
at random, and putting my finger in and reading the sentences on that page,
I can show you what's the matter -- how it's not science, but memorizing, in
every circumstance. Therefore I am brave enough to flip through the pages
now, in front of this audience, to put my finger in, to read, and to show
you."
So I did it. Brrrrrrrup -- I stuck my finger in, and I started to read:
"Triboluminescence. Triboluminescence is the light emitted when crystals are
crushed..."
I said, "And there, have you got science? No! You have only told what a
word means in terms of other words. You haven't told anything about nature
-- what crystals produce light when you crush them, why they produce light.
Did you see any student go home and try it? He can't.
"But if, instead, you were to write, 'When you take a lump of sugar and
crush it with a pair of pliers in the dark, you can see a bluish flash. Some
other crystals do that too. Nobody knows why. The phenomenon is called
"triboluminescence." ' Then someone will go home and try it. Then there's an
experience of nature." I used that example to show them, but it didn't make
any difference where I would have put my finger in the book; it was like
that everywhere.
Finally, I said that I couldn't see how anyone could be educated by
this self-propagating system in which people pass exams, and teach others to
pass exams, but nobody knows anything. "However," I said, "I must be wrong.
There were two Students in my class who did very well, and one of the
physicists I know was educated entirely in Brazil. Thus, it must be possible
for some people to work their way through the system, bad as it is."
Well, after I gave the talk, the head of the science education
department got up and said, "Mr. Feynman has told us some things that are
very hard for us to hear, but it appears to be that he really loves science,
and is sincere in his criticism. Therefore, I think we should listen to him.
I came here knowing we have some sickness in our system of education; what I
have learned is that we have a cancer!" -- and he sat down.
That gave other people the freedom to speak out, and there was a big
excitement. Everybody was getting up and making suggestions. The students
got some committee together to mimeograph the lectures in advance, and they
got other committees organized to do this and that.
Then something happened which was totally unexpected for me. One of the
students got up and said, "I'm one of the two students whom Mr. Feynman
referred to at the end of his talk. I was not educated in Brazil; I was
educated in Germany, and I've just come to Brazil this year."
The other student who had done well in class had a similar thing to
say. And the professor I had mentioned got up and said, "I was educated here
in Brazil during the war, when, fortunately, all of the professors had left
the university, so I learned everything by reading alone. Therefore I was
not really educated under the Brazilian system."
I didn't expect that. I knew the system was bad, but 100 percent -- it
was terrible!
Since I had gone to Brazil under a program sponsored by the United
States Government, I was asked by the State Department to write a report
about my experiences in Brazil, so I wrote out the essentials of the speech
I had just given. I found out later through the grapevine that the reaction
of somebody in the State Department was, "That shows you how dangerous it is
to send somebody to Brazil who is so naive. Foolish fellow; he can only
cause trouble. He didn't understand the problems." Quite the contrary! I
think this person in the State Department was naive to think that because he
saw a university with a list of courses and descriptions, that's what it
was.

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