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A reply from Earth: Just send them the encyclopaedia
Acta Astronautica Vol. 29, No. 3, pp. 233-235, 1993
0094-5765/93 $6.00 + 0.00 Copyright © 1993 Pergamon Press Ltd
Printed in Great Britain. All rights reserved
Academy Transactions Note A REPLY FROM EARTH: JUST SEND THEM THE ENCYCLOPAEDIAt JEAN HEIDMANN~
Paris Observatory, F-92195 Meudon, France (Received 13 November 1992)
Abstract--Without consideration of eventual specific points raised by an extraterrestrial message, we suggest that the best material to be sent as a first reply is a current encyclopaedia. It satisfies the reasonable criteria known to date.
1. INTRODUCTION
The Declaration of principles concerning activities following the detection of extraterrestrial intelligence states in its article No. 8 that "No response to a signal or other evidence of extraterrestrial intelligence should be sent until appropriate international consultations have taken place. The procedures for such consultations will be the subject of separate agreement, declaration or arrangement" [1]. Assuming that we do answer, the question of the content of the answer has to be resolved. At the Balaton 1987 Bioastronomy IAU Colloquium, Goldsmith stressed the main points that an answer from the Earth to a message from extraterrestrials (ETs) should comply with[2]. Aware of the confusion which will be generated about the answer when a signal is detected, he stated that an answer agreed upon before, even by a restricted portion of our society, such as the researchers already engaged in SETI, would have a better chance to be seriously considered by ETs. The best odds will go to a clear, intelligible and interesting answer, rather than to a weak, garbled and confused message. The real issue is, in the end, to achieve dialogue, in spite of the very long durations of the exchanges. I think that even on Earth we have already interesting examples of intelligent civilizations with very long durations. Homo erectus had the "biface" technology for one million years[3] and high level artists, from Perigordians to Magdalenians, produced parietal art for fifteen thousand years [4]. Note that these terrestrial cases give very encouraging support for increasing the probability that we detect extraterrestrial civilizations because, according tPrepared for the IAA SETI Committee Business Meeting, Washington, D.C., 1992. :~IAA Corresponding Member (Section Basic Sciences).
to Drake's equation, this probability of success is proportional to the civilization duration. In this perspective Homo erectus provides SETI with an example of a civilization spanning the million of years, rough of course, but intelligent and technologically engaged. This being said, it is then reasonable, provided we look above the short span of our individual life, to consider dialogues between civilizations across galactic distances. In particular the NASA SETI Target Search[5] may uncover candidates for century-long dialogues while the Sky Survey[5] may do it for hundred centuries-long ones. Goldsmith notes that in case we get a signal, it will statistically come from ETs already in relation with other "ET correspondents" and that we shall be in sharp competition with these. Thus the level of our first answer will be of critical importance for the initiation of further dialogue. He also notes that it will be difficult to get a general concensus on Earth for the content of our answer. Though there is not really a limit on its extent, the main problems will arise from the "lust for censorship from various segments of our culture ( . . . ) , as attempts on the part of organized religions to present their theology as human truth, or on the part of governments to engage in similar exercise".
2. A PRAGMATIC APPROACH
In addition to Goldsmith, a few other workers gave general principles about a reply from the Earth: Reijnen[6], Cocca[7], Billingham[8], Michaud[9] and Michaud et al.[10]. These focus mainly on procedures. Reijnen gives some elements about content, such as stating that intelligent life exists here, that we did receive the signals, indicating our location, main features, desire for dialogue. 233
234
JEAN HEIDMANN
Here I adopt a pragmatic point of view and shall suggest an answer which satisfies the following requirements: (1) it attempts to get a wide as possible first consensus from the Earth SETI community, (2) it deals with Goldsmith's concern about censorship, (3) it contains as much as possible valuable information, (4) it is the most intelligible in its coding and in its structure, (5) it is already completely formulated, (6) it is transmissible with our present technology.
3. THE ENCYCLOPAEDIAS
The oldest encyclopaedia known is Chinese and dates back from 500 BC, while Pliny the Elder's Natural History is among the first in the Western world. The first modern encyclopaedia appeared in the 17th to 18th centuries as compendia providing easy references for students and learned people, organizing subjects by themes and more and more by alphabetical order. The most famous is the French one by Diderot and d'Alembert, published in 1772, with 17 volumes for the text and 11 for the illustrations, providing a synthesis of knowledge and ideas. The Encyclopaedia Britannica appeared in 1771 and since 1920 is published in the U.S. Other major countries followed: Germany in 1810, former Soviet Union and Italy[ll]. A typical modern one is the Corpus de l'Encyclopaedia Universalis, compiled over the years by a staff of 60 in collaboration with 4000 international researchers and scientists. Already sold 500,000 copies since its start in 1985, its 24 volumes comprises 26,000 pages, 6000 articles, 30,000 illustrations and 190 million typographic signs. Its main guide lines are intellectual independence, pluralism and access understanding[12]. In comparison, a dictionary usually aims at simply defining words with examples stressing the grammatical aspects and sometimes providing explanations. The first dates from the second century; the most famous French are the Dictionnaire de l'Acadkrnie, first published in 1694, the Littr6 (1873), the Robert (1964). In between one finds also encyclopaedic dictionaries [! 1]. 4. AN ENCYCLOPAEDIA AS AN ANSWER
All in all it is clear that major encyclopaedias, like the Britannica or the Universalis, answer the criteria listed in the previous section: (1) their vast diffusion, then their acknowledgement, insure their recognition by a large portion of the Earth society and the best chance for a wide consensus;
(2) they are the output of a very wide section of all human learned people, from all disciplines, with all philosophical points of view and nationalities, aiming at insuring to them an impartial, factual and scientific spirit; (3) they contain a maximum amount of valuable information in a single piece of work, this being their
raison d'etre; (4) they are essentially a linear string of typographic signs (the text) and a set of bidimensional arrays of pixels (the illustrations) whose coding is elementary. The alphabetical coding can be deciphered using just a few pages, as well as the grammatical structures. The illustrations are also obviously decodable by any ETs using bidimensional information from their own environment. The coupling between text and illustrations will easily provide information nearly ad infinitum. From them the structure of the access to the corpus will also be easily decodable; (5) they are already available, always in an up to date version, even to a point where themes like "bioastronomy" are included; (6) they are easily transmissible; the text can be coded into one billion bits while the illustrations, comprising billions of pixels, can be coded with 100 billion bits or so. With a 10 MHz transmiting band, the complete transmission would take only 3 hours. 5. STRATEGY
Of course, when a signal is received, we should learn much technical information about their senders; position on the sky, distance, frequency used, frequency resolution, total bandwidth, power, duty cycle, primary coding, even information on the ETs and their purpose. Though such matters as the ones noted by Reijnen would be de facto included in the encyclopaedic corpus, they could be sent as a short "preface" to it. Even a short version of the corpus, such as a college edition, could be added as a stepping stone; its content, with reduced illustrations, amounts to only 100 million bits, transmissible faster and/or at a larger power level. It is my feeling that the Encyclopaedia solution would better work if we agree to send all of it. Statistically our ET correpondents should be much more educated than we are; then it seems worthless, for instance, to try to hide some of our "bad" aspects by omiting to transmit them; they would show anyway! And why wouldn't we hope that a general large scale study of all of our encyclopaedia by ETs would provide them with a nevertheless not so bad idea of us? Furthermore, when we send all of it, we provide right now a maximum of information to our correspondents, which is the best we can do for a better eventual future dialogue between them and our decendants of the next centuries.
Reply ffomEarth 6. WHEN TO SEND THE ENCYCLOPAEDIA?
When to send it? Personally I would send it as soon as we are able to decipher some relevant information on the origin of the signals. This is a very vague strategy because we may fall in any situation between these two: - - w e only learn that the signal is artificial, intentional or non-intentional, like pi or a technical astro-engineering radio frequency interference; - - w e face a very difficult and progressive decoding which may take years, like the investigation o f a new domain of science suddenly open to us. This question of when to answer, not yet addressed to my knowledge, should be investigated by a special body of learned people. REFERENCES
1. J. Billingham, M. Michaud and J, Tarter, Declaration of principles concerning activities following the detection of extraterrestrial intelligence. Bioastronomy, The Search for Extraterrestrial Life; The Exploration Broadens (Edited by J. Heidmann and M. J. Klein), p. 379. Springer, Heidelberg (1991).
235
2. D. Goldsmith, Who will speak for Earth? Bioastronomy, The Next Steps (Edited by G. Marx), p. 425. Kluver, Dordrecht (1988). 3. Y. Coppens, Le singe, I'Afrique et rhomme. Librairie Arth~me Fayard, Paris (1983). 4. H. de Lumley, Origine et bvolution de I'homme. Mus6um National d'Histoire Naturelle, Paris (1982). 5. J. Tarter and M. J. Klein, SETI: on the telescope and on the drawing board. Bioastronomy, The Search for Extraterrestrial Life; The Exploration Broadens (Edited by J. Heidmann and M. J. Klein), p. 229. Springer, Heidelberg (1991). 6. G. C. M. Reijnen, Basic elements for an international terrestrial reply following the detection of a signal from extraterrestrial intelligence. Acta Astronautica 21, 143 (1990). 7. A. A. Cocca, XII tables for researchers on extraterrestrial intelligence. Acta Astronautica 21, 127 (1990). 8. J. Billingham, International policy on reply from Earth. White Paper presented at the Business Meeting of the IAA SETI Committee, Montreal (1991). 9. M. A. G. Michaud, An international agreement concerning the detection of extraterrestrial intelligence. Acta Astronautica 26, 291 (1992). I0. M. A. G. Michaud, J. Billingham and J. Tarter, A reply from Earth? Acta Astronautica 26, 295 (1992). 11. Nouvelle Encyclopbdie Bordas, Paris (1985). 12. Club Franfais du Livre--Encyclopaedia universalis, Paris (1992).
0094-5765/93 $6.00 + 0.00 Copyright © 1993 Pergamon Press Ltd
Printed in Great Britain. All rights reserved
Academy Transactions Note A REPLY FROM EARTH: JUST SEND THEM THE ENCYCLOPAEDIAt JEAN HEIDMANN~
Paris Observatory, F-92195 Meudon, France (Received 13 November 1992)
Abstract--Without consideration of eventual specific points raised by an extraterrestrial message, we suggest that the best material to be sent as a first reply is a current encyclopaedia. It satisfies the reasonable criteria known to date.
1. INTRODUCTION
The Declaration of principles concerning activities following the detection of extraterrestrial intelligence states in its article No. 8 that "No response to a signal or other evidence of extraterrestrial intelligence should be sent until appropriate international consultations have taken place. The procedures for such consultations will be the subject of separate agreement, declaration or arrangement" [1]. Assuming that we do answer, the question of the content of the answer has to be resolved. At the Balaton 1987 Bioastronomy IAU Colloquium, Goldsmith stressed the main points that an answer from the Earth to a message from extraterrestrials (ETs) should comply with[2]. Aware of the confusion which will be generated about the answer when a signal is detected, he stated that an answer agreed upon before, even by a restricted portion of our society, such as the researchers already engaged in SETI, would have a better chance to be seriously considered by ETs. The best odds will go to a clear, intelligible and interesting answer, rather than to a weak, garbled and confused message. The real issue is, in the end, to achieve dialogue, in spite of the very long durations of the exchanges. I think that even on Earth we have already interesting examples of intelligent civilizations with very long durations. Homo erectus had the "biface" technology for one million years[3] and high level artists, from Perigordians to Magdalenians, produced parietal art for fifteen thousand years [4]. Note that these terrestrial cases give very encouraging support for increasing the probability that we detect extraterrestrial civilizations because, according tPrepared for the IAA SETI Committee Business Meeting, Washington, D.C., 1992. :~IAA Corresponding Member (Section Basic Sciences).
to Drake's equation, this probability of success is proportional to the civilization duration. In this perspective Homo erectus provides SETI with an example of a civilization spanning the million of years, rough of course, but intelligent and technologically engaged. This being said, it is then reasonable, provided we look above the short span of our individual life, to consider dialogues between civilizations across galactic distances. In particular the NASA SETI Target Search[5] may uncover candidates for century-long dialogues while the Sky Survey[5] may do it for hundred centuries-long ones. Goldsmith notes that in case we get a signal, it will statistically come from ETs already in relation with other "ET correspondents" and that we shall be in sharp competition with these. Thus the level of our first answer will be of critical importance for the initiation of further dialogue. He also notes that it will be difficult to get a general concensus on Earth for the content of our answer. Though there is not really a limit on its extent, the main problems will arise from the "lust for censorship from various segments of our culture ( . . . ) , as attempts on the part of organized religions to present their theology as human truth, or on the part of governments to engage in similar exercise".
2. A PRAGMATIC APPROACH
In addition to Goldsmith, a few other workers gave general principles about a reply from the Earth: Reijnen[6], Cocca[7], Billingham[8], Michaud[9] and Michaud et al.[10]. These focus mainly on procedures. Reijnen gives some elements about content, such as stating that intelligent life exists here, that we did receive the signals, indicating our location, main features, desire for dialogue. 233
234
JEAN HEIDMANN
Here I adopt a pragmatic point of view and shall suggest an answer which satisfies the following requirements: (1) it attempts to get a wide as possible first consensus from the Earth SETI community, (2) it deals with Goldsmith's concern about censorship, (3) it contains as much as possible valuable information, (4) it is the most intelligible in its coding and in its structure, (5) it is already completely formulated, (6) it is transmissible with our present technology.
3. THE ENCYCLOPAEDIAS
The oldest encyclopaedia known is Chinese and dates back from 500 BC, while Pliny the Elder's Natural History is among the first in the Western world. The first modern encyclopaedia appeared in the 17th to 18th centuries as compendia providing easy references for students and learned people, organizing subjects by themes and more and more by alphabetical order. The most famous is the French one by Diderot and d'Alembert, published in 1772, with 17 volumes for the text and 11 for the illustrations, providing a synthesis of knowledge and ideas. The Encyclopaedia Britannica appeared in 1771 and since 1920 is published in the U.S. Other major countries followed: Germany in 1810, former Soviet Union and Italy[ll]. A typical modern one is the Corpus de l'Encyclopaedia Universalis, compiled over the years by a staff of 60 in collaboration with 4000 international researchers and scientists. Already sold 500,000 copies since its start in 1985, its 24 volumes comprises 26,000 pages, 6000 articles, 30,000 illustrations and 190 million typographic signs. Its main guide lines are intellectual independence, pluralism and access understanding[12]. In comparison, a dictionary usually aims at simply defining words with examples stressing the grammatical aspects and sometimes providing explanations. The first dates from the second century; the most famous French are the Dictionnaire de l'Acadkrnie, first published in 1694, the Littr6 (1873), the Robert (1964). In between one finds also encyclopaedic dictionaries [! 1]. 4. AN ENCYCLOPAEDIA AS AN ANSWER
All in all it is clear that major encyclopaedias, like the Britannica or the Universalis, answer the criteria listed in the previous section: (1) their vast diffusion, then their acknowledgement, insure their recognition by a large portion of the Earth society and the best chance for a wide consensus;
(2) they are the output of a very wide section of all human learned people, from all disciplines, with all philosophical points of view and nationalities, aiming at insuring to them an impartial, factual and scientific spirit; (3) they contain a maximum amount of valuable information in a single piece of work, this being their
raison d'etre; (4) they are essentially a linear string of typographic signs (the text) and a set of bidimensional arrays of pixels (the illustrations) whose coding is elementary. The alphabetical coding can be deciphered using just a few pages, as well as the grammatical structures. The illustrations are also obviously decodable by any ETs using bidimensional information from their own environment. The coupling between text and illustrations will easily provide information nearly ad infinitum. From them the structure of the access to the corpus will also be easily decodable; (5) they are already available, always in an up to date version, even to a point where themes like "bioastronomy" are included; (6) they are easily transmissible; the text can be coded into one billion bits while the illustrations, comprising billions of pixels, can be coded with 100 billion bits or so. With a 10 MHz transmiting band, the complete transmission would take only 3 hours. 5. STRATEGY
Of course, when a signal is received, we should learn much technical information about their senders; position on the sky, distance, frequency used, frequency resolution, total bandwidth, power, duty cycle, primary coding, even information on the ETs and their purpose. Though such matters as the ones noted by Reijnen would be de facto included in the encyclopaedic corpus, they could be sent as a short "preface" to it. Even a short version of the corpus, such as a college edition, could be added as a stepping stone; its content, with reduced illustrations, amounts to only 100 million bits, transmissible faster and/or at a larger power level. It is my feeling that the Encyclopaedia solution would better work if we agree to send all of it. Statistically our ET correpondents should be much more educated than we are; then it seems worthless, for instance, to try to hide some of our "bad" aspects by omiting to transmit them; they would show anyway! And why wouldn't we hope that a general large scale study of all of our encyclopaedia by ETs would provide them with a nevertheless not so bad idea of us? Furthermore, when we send all of it, we provide right now a maximum of information to our correspondents, which is the best we can do for a better eventual future dialogue between them and our decendants of the next centuries.
Reply ffomEarth 6. WHEN TO SEND THE ENCYCLOPAEDIA?
When to send it? Personally I would send it as soon as we are able to decipher some relevant information on the origin of the signals. This is a very vague strategy because we may fall in any situation between these two: - - w e only learn that the signal is artificial, intentional or non-intentional, like pi or a technical astro-engineering radio frequency interference; - - w e face a very difficult and progressive decoding which may take years, like the investigation o f a new domain of science suddenly open to us. This question of when to answer, not yet addressed to my knowledge, should be investigated by a special body of learned people. REFERENCES
1. J. Billingham, M. Michaud and J, Tarter, Declaration of principles concerning activities following the detection of extraterrestrial intelligence. Bioastronomy, The Search for Extraterrestrial Life; The Exploration Broadens (Edited by J. Heidmann and M. J. Klein), p. 379. Springer, Heidelberg (1991).
235
2. D. Goldsmith, Who will speak for Earth? Bioastronomy, The Next Steps (Edited by G. Marx), p. 425. Kluver, Dordrecht (1988). 3. Y. Coppens, Le singe, I'Afrique et rhomme. Librairie Arth~me Fayard, Paris (1983). 4. H. de Lumley, Origine et bvolution de I'homme. Mus6um National d'Histoire Naturelle, Paris (1982). 5. J. Tarter and M. J. Klein, SETI: on the telescope and on the drawing board. Bioastronomy, The Search for Extraterrestrial Life; The Exploration Broadens (Edited by J. Heidmann and M. J. Klein), p. 229. Springer, Heidelberg (1991). 6. G. C. M. Reijnen, Basic elements for an international terrestrial reply following the detection of a signal from extraterrestrial intelligence. Acta Astronautica 21, 143 (1990). 7. A. A. Cocca, XII tables for researchers on extraterrestrial intelligence. Acta Astronautica 21, 127 (1990). 8. J. Billingham, International policy on reply from Earth. White Paper presented at the Business Meeting of the IAA SETI Committee, Montreal (1991). 9. M. A. G. Michaud, An international agreement concerning the detection of extraterrestrial intelligence. Acta Astronautica 26, 291 (1992). I0. M. A. G. Michaud, J. Billingham and J. Tarter, A reply from Earth? Acta Astronautica 26, 295 (1992). 11. Nouvelle Encyclopbdie Bordas, Paris (1985). 12. Club Franfais du Livre--Encyclopaedia universalis, Paris (1992).