"If successful, the airscooter trial at Nasa's Ames research centre in California could form another stepping stone in the development of personal, individual aircraft that allow commuters to speed over traffic jams..."
...until they collide with a swarming mass of other commuters attempting to avoid said traffic jams....
There is a solid technological solution to eliminate this problem.
A couple of groups (for example, open source tuneprint, and the company *CD) have developed the technology to create a "fingerprint" of an audio track. The beauty of this solution is that it can tell you how "close", in some quantifiable sense, any track is to a centrally archived version, independent of the track format (mp3, wav, what have you). Since they run their inputs through psychacoustic models, *ANY* tracks which *sound* alike are deemed similar. Corrupted tracks and spam are easily eliminated.
Of course, Napster has enough legal difficulties without attempting to validate what they are serving up. Look for this technology in future incarnations of Napster, after the current one is shut down by the current court case, or yet-to-be-passed congressional legistlation.
It is remarkable that consciousness of the importance of MPEG-4 has leaked out into the wider, technical (though not necessarily hacker) community. There was an interesting column in Scientific American last month with history and some analysis that complements this article.
Note that the basic physics requires the center-of-mass point to be in geostationary orbit; that requires a huge mass to be tied down to the other end. The article suggests an asteroid. People have often mentioned moving asteroids into Earth orbit for mining purposes, but that is just incredibly unlikely, not from a technical perspective (where we can always speculate on future technologies) but rather from a political one. Just imagine the public backlash if one suggested to move a few-km sized rock, capable of a 100 hydrogen bomb explosion, and able to wipe out most of life on Earth. Sure, you may have the technology, but one minor slip-up...
Given our previous experience with small missions (think Challenger, Galileo, Mars missions...), there is a significant probably of disaster...
There are ways around this; the most obvious being importing lunar regolith for both the elevator and the counterweight. However, even the moon has a small gravitational field, even though it is much less than the Earth's. The net impact is one must still boost billions of tons of mass into place before _any_ useful work can be done with the elevator. You will need some _very_ large scale projects in mind to justify its existence.
To me, it seems much more feasible to use the moon or the asteroids themselves as the launching point for large-scale projects. Almost all of the basic materials are already there. Water and other volatiles can be shipped up from Earth when necessary.
(1) It seems that most posters fail to appreciate that this form of distributing computing is limited to problems which are essentially "trivially parallelizable". Anyone who has done parallel computations knows that MOST interesting parallel algorithms MUST exchange information with other processors while doing useful computation. Both the bandwidth and the latency over the internet will NEVER come close to matching what can be found inside a high-end parallel machine where the processors are all mounted in a single unit. The performance of any "coupled" problem, be it a traffic simulation or a climate model, will be absolutely dog poor on these widely distributed computer networks.
All said, this is still a very cool concept for SOME projects, like distributed rendering for films, and analysis of vast quantities of data (ala SETI@home). One shouldn't underestimate the marketing value in a distributed rendering project for a film, either! (Who wouldn't go see a film they had helped render on their PC! Especially if one could "preview" the result as it was being rendered.) But I think that this form of distributed computing will tend to be a niche, rander than a general solution for scientists and technologists with parallel computing needs.
This was quite an interesting list, but let's not forget who came up with it -- a group of string theorists. The list reflects a certain... severe bias, in that ALL of the problems lie in the fields of high energy physics and cosmology. They completely ignore the equally fascinating (and much more rapidly growing) fields of condensed matter physics, biophysics, geophysics, and astrophysics (apart from cosmology). These fields promise to change our world, both in terms of the gadgets we use, to our very genetic essence, and contain problems of significant scientific merit as well.
This point reminds me of a listing posted to slashdot a couple of months ago of the top ten algorithms of all time. It just so happened that all ten were numerical algorithms, reflecting the bias of the poster in that case as well. A more objective list requires a more universal panel.
For all of its technical wisdom, and fascination with space exploration and science fiction, I am very surprised how clueless most Slashdot folks (including the poster) are on this one.
First, NASA has sent redundant probes before. Many times. Consider : Viking 1 and 2 to Mars, Pioneer 10 and 11 and Voyager 1 and 2 to the outer solar system... the list goes on and on.
Second, the cost of the second mission is far less than the first. The bulk of the expense of a space mission is sunk into the research and development of the probe, and subsequent mission support over its lifetime... not in the material manufacture or in the launch (though these are substantial in and of themselves).
In sum, two missions can be done for less than twice the cost of one mission, and you gain enormously by redundancy. Random catastrophes are unlikely to strike both probes simultaneously, and system difficulties with the first mission can be detected and solved in the intervening time before the second probe arrives.
This makes "faster, cheaper, better" missions more feasible. These missions are being launched on mere dimes where dollars were spent before. The problem is that they have suffered from reliability issues. Two missions for the price of 1.5 missions gives one _both_ reliability and low cost.
The basic assumption here seems simple enough : everyone is free to do as the choose so long as they don't hamper or endanger the freedom of others.
However, just because one is free does not mean that one will make the decisions that will enable one to live the best life one possibly can, in some sense.
For instance, the Libertarian.org site discusses one application of the Libertarian philosophy : science and technology. They state that they feel that science and technology can do better without the "aid" (quotes theirs) of government.
This is a very curious position. The basic science and technology research which is pursued in our nation and others would be entirely impossible without large-scale funding from government agencies, which are ultimately supported by taxation. If directly asked whether they would support most science endeavors through personal donations, most citizens would flatly refuse -- they simply don't enough about the research fields involved. Even _scientists_ have difficulty deciding which projects should be funded -- hence the need for peer-reviewed funding agencies like NSF, NIST, NASA, etc. Yet, one cannot deny the huge impact which such research has had on our lives -- basical medical advances, fundamental knowledge of the universe, semiconductor technologies -- all would be impossible without the basic and applied research pursued by government.
The biggest payoff of one such gamble was the DARPA project funded in the late 1960s that would eventually flourish into the internet we know today. Under the Liberterian ideals espoused, the internet would not exist today.
In a nutshell, every individual simply does _not_ know what is best for themselves. The massive amounts of knowledge and technical know-how are distributed throughout the members of our society, and it is sheer hubris to think that any individual can make basic research decisions (in effect, by donations) better than the collective of all scientists and technologists in the nation. It is true that one sacrifices some amount of freedom by willingly supporting their decisions through taxation, but in exchange one receives all of the knowledge, and technical and medical advances which our society has received by supporting basic and applied research on large scales.
Libertertian.org is here today because of definitively non-Liberterian principles.
This sounds like a technological urban legend to me.
Note that radio frequencies are in the MILLIONS of cycles per second, wheras acoustic frequencies are TENS to THOUSANDS. The resultant frequency modulations would be almost entirely imperceptible on the scale of the FM band, over many MHz. Indeed, the way modern radio systems encode and decode the signal is through the use of heterodyne techniques; the signal is essentially detected as interference "beats" against a standard frequency reference.
Many people, including Jon here, have used the argument that since CD sales have been on the rise over the last severl years, there is no evidence for damage done by mp3-swapping.
Note however, that there are a myriad of causes for this growth (including the overall growth in the economy), and simply looking at net sales will not disentangle the causes. The question is not whether CD sales have increased, but what is the net effect of mp3-swapping on this growth? The answer is not obvious, since broadband net access is still only enjoyed by a minority, and so the effect of mp3-swapping is still insignificant in comparison to total sales. However, as more and more home users get broadband access, we can expect this effect to become very significant.
My own opinion is that the current effect of mp3-swapping is small and negative, but we can expect it to grow to enormous proportions in ten years or less, as the recording industry continues to fight a losing war.
This model will probably come to pass, but this company will not be the one to do it.
Legally, they will get nailed, just as mp3.com already has (for Beam-It) and Napster will be. Quite simply, they don't own any of the licenses for the music they are trafficking in, much less the users who have simply ripped a few tracks from a CD they own. What legal rights does a pirate have for compensation for his pirated works? Nada.
Postulate. The RIAA companies will initiate such a service soon, after Napster and its competitors have been shut down.
The genie is out of the bottle with regards to mp3 files. No amount of interference can stop the illegal trade of mp3 files amongst users. The best the RIAA companies can do is to act as a middleman. People will be willing to pay a premium to have the service of a Napster-like central repository. Anyone who has used both Napster and Gnutella has realized that Napster's central sercer system is the way to go here in terms of speedy searches, and is superior to Gnutella for the trade of mp3 files. People will be willing to pay a small amount for that service.
The inevitable conclusion is that the RIAA companies may eventually act as middleman between users trading mp3 files. However, they will not offer microcharges as small as.25, since that will hurt their CD sales. Expect $1 - $2/ track charges. Their monopoloy on the licensing of the songs will allow them to do this.
However, mp3.com has purchased liscensing agreements recently with members of the RIAA (Warner, BMG) for its 'Beam-It' tool. The RIAA and its members DO NOT want to see mp3.com shut down, since 'Beam-It' presents just about the best opportunity for them to offer positive incentives to purchase more CDs while still protecting their property rights.
This is the real world, and the real world is not clean : mp3.com works with both the RIAA and independent artists. If you are really bent on sticking to principles, you should ban mp3.com as well. However, a more moderate stance is that we need both moderates and extremists pushing from both sides to really advance.
What was interest about this (to me at least) was just how _long_ ago most of the inductees had done their work. The Yahoo article mentioned that Helen Free and Woz were the only two living awardees out of seven. Most of the work was done in the 1940s...
Also, when flipping through a few of the list of previous awardees, you begin to sense just how ancient the patent office seems. Almost all were for some type of gadget.
Will we see Jeff Bezos and Amazon inducted into the hall in 2060 for patents which changed the way the web worked?;-)
Bob
Re:wacked / social life / building institutions
on
ArsDigita University
·
· Score: 1
DGregory :
As I see it, accreditation is not the most important issue. The issue is how you are viewed in the eyes of others. Hence, if this program survives for several years, and is able to graduate top notch people with some incredible talent, then it won't take long for employers to identify ArsDigita U backgrounds just as employers identify people with Caltech, Berkeley, M.I.T., Stanford, etc. backgrounds. Every institution must start somewhere, and I would argue that the quality of graduates is actually far more important than a piece of paper hanging in the administratives offices in a university hall.
With regards to social life, ask anyone who got a B.S. from Caltech or M.I.T. what kind of social life they had for four years. 12 hours a day, 7 days a week, is being conservative. And that was for four years, not one...
Let's see if we can make an educated estimate as to how long it would take to power a standard-type laptop battery.
The solar constant at the location of the earth (luminosity of sun / (4 pi distance_from_sun_to_earth^2) ) is 1370 w / m^2. Let's be generous, assume the collecting area is 1 m^2. Let's also call things roughly. Per hour, that translates into (3600 s) (1 KW/m^2) 1 m^2 ~4 10^6 J. Let's say that a solar cell can have an efficiency of about 1%. That translates into 4 10^4 J = 40 KJ of energy.
How much energy does a typical battery store? State of the art chemical batteries typically have energy densities of 1 KWh / kg, or roughly 10^6 J/ kg, as above. This means that to charge a 1 kg battery, roughly 100 hours are required.
Even if the efficiency were as high as 10%, about 10 hours would be required to charge. Hence, it seems that the concept is good, but it would take at least a full day in sunlight to charge up a laptop battery. Not very practical, considering that the very idea of a laptop is to be mobile...
This story reminds me of an occassion when Richard Feynman was giving an informal talk at the Esalen Institute, a new-agey institute on the California coast between Los Angeles and San Francisco that he was known to frequent.
He was explaining the properties of matter (comparing atoms vibrating in a lattice to band members marching in step), when a guy from the audience interrupted and starting asking about antigravity devices.
Feynman, in his typical blunt manner, said something to the effect of, "Fella, what you are talking about is impossible. It violates fundamental principles of physics. What _is_ a great antigravity device is that seat under your butt."
Re:Galileo -- the "martyr" who wasn't
on
Galileo's Daughter
·
· Score: 1
I have to disagree with Zach on a couple of points.
First, I think that as a matter of principle, freedom of speech should allow one to profess whatever notions or beliefs that one cares to express. It is not the role of higher authorities and institutions to judge the validity of those beliefs, but rather the free marketplace of ideas. The Church's use of a house arrest, no matter how benign, is in fact an instance of state repression of personal expression, and is quite in conflict with the principle of freedom of speech. Of course, this is a modern notion, and we should acknowledge that the very concept of such freedom didn't exist in the 17th century. However, this does not justify the Catholic Church's actions in any fashion.
Second, I think that the key point of Sagan's books and videos is that they tried to instill the notion of rational skepticism in their respective audiences. In a world filled with pseudo-scientific garbage (astrology, Scientology, etc.) such voices are very desperately needed. The minds and hearts of future voters and taxpayers are at stake, and it is critical that we demonstrate the worth of rational thinking in evaluating ideas to them.
Slashdot Mirror
"If successful, the airscooter trial at Nasa's Ames research centre in California could form another stepping stone in the development of personal, individual aircraft that allow commuters to speed over traffic jams..."
...until they collide with a swarming mass of other commuters attempting to avoid said traffic jams....
I can add one to that list : I met my girlfriend online! Then again, since that time, we have not been strictly virtual... ;-)
Bob
Mercury is a very well-known toxic substance which is easily converted to vapor and inhaled at room temperature.
Give me a nice, safe x-ray emitting CRT for my computational astrophysics any day...
Bob
A couple of groups (for example, open source tuneprint, and the company *CD) have developed the technology to create a "fingerprint" of an audio track. The beauty of this solution is that it can tell you how "close", in some quantifiable sense, any track is to a centrally archived version, independent of the track format (mp3, wav, what have you). Since they run their inputs through psychacoustic models, *ANY* tracks which *sound* alike are deemed similar. Corrupted tracks and spam are easily eliminated.
Of course, Napster has enough legal difficulties without attempting to validate what they are serving up. Look for this technology in future incarnations of Napster, after the current one is shut down by the current court case, or yet-to-be-passed congressional legistlation.
Bob
It is remarkable that consciousness of the importance of MPEG-4 has leaked out into the wider, technical (though not necessarily hacker) community. There was an interesting column in Scientific American last month with history and some analysis that complements this article.
Note that the basic physics requires the center-of-mass point to be in geostationary orbit; that requires a huge mass to be tied down to the other end. The article suggests an asteroid. People have often mentioned moving asteroids into Earth orbit for mining purposes, but that is just incredibly unlikely, not from a technical perspective (where we can always speculate on future technologies) but rather from a political one. Just imagine the public backlash if one suggested to move a few-km sized rock, capable of a 100 hydrogen bomb explosion, and able to wipe out most of life on Earth. Sure, you may have the technology, but one minor slip-up...
Given our previous experience with small missions (think Challenger, Galileo, Mars missions...), there is a significant probably of disaster...
There are ways around this; the most obvious being importing lunar regolith for both the elevator and the counterweight. However, even the moon has a small gravitational field, even though it is much less than the Earth's. The net impact is one must still boost billions of tons of mass into place before _any_ useful work can be done with the elevator. You will need some _very_ large scale projects in mind to justify its existence.
To me, it seems much more feasible to use the moon or the asteroids themselves as the launching point for large-scale projects. Almost all of the basic materials are already there. Water and other volatiles can be shipped up from Earth when necessary.
Bob
(1) It seems that most posters fail to appreciate that this form of distributing computing is limited to problems which are essentially "trivially parallelizable". Anyone who has done parallel computations knows that MOST interesting parallel algorithms MUST exchange information with other processors while doing useful computation. Both the bandwidth and the latency over the internet will NEVER come close to matching what can be found inside a high-end parallel machine where the processors are all mounted in a single unit. The performance of any "coupled" problem, be it a traffic simulation or a climate model, will be absolutely dog poor on these widely distributed computer networks.
All said, this is still a very cool concept for SOME projects, like distributed rendering for films, and analysis of vast quantities of data (ala SETI@home). One shouldn't underestimate the marketing value in a distributed rendering project for a film, either! (Who wouldn't go see a film they had helped render on their PC! Especially if one could "preview" the result as it was being rendered.) But I think that this form of distributed computing will tend to be a niche, rander than a general solution for scientists and technologists with parallel computing needs.
This was quite an interesting list, but let's not forget who came up with it -- a group of string theorists. The list reflects a certain... severe bias, in that ALL of the problems lie in the fields of high energy physics and cosmology. They completely ignore the equally fascinating (and much more rapidly growing) fields of condensed matter physics, biophysics, geophysics, and astrophysics (apart from cosmology). These fields promise to change our world, both in terms of the gadgets we use, to our very genetic essence, and contain problems of significant scientific merit as well.
This point reminds me of a listing posted to slashdot a couple of months ago of the top ten algorithms of all time. It just so happened that all ten were numerical algorithms, reflecting the bias of the poster in that case as well. A more objective list requires a more universal panel.
For all of its technical wisdom, and fascination with space exploration and science fiction, I am very surprised how clueless most Slashdot folks (including the poster) are on this one.
First, NASA has sent redundant probes before. Many times. Consider : Viking 1 and 2 to Mars, Pioneer 10 and 11 and Voyager 1 and 2 to the outer solar system... the list goes on and on.
Second, the cost of the second mission is far less than the first. The bulk of the expense of a space mission is sunk into the research and development of the probe, and subsequent mission support over its lifetime... not in the material manufacture or in the launch (though these are substantial in and of themselves).
In sum, two missions can be done for less than twice the cost of one mission, and you gain enormously by redundancy. Random catastrophes are unlikely to strike both probes simultaneously, and system difficulties with the first mission can be detected and solved in the intervening time before the second probe arrives.
This makes "faster, cheaper, better" missions more feasible. These missions are being launched on mere dimes where dollars were spent before. The problem is that they have suffered from reliability issues. Two missions for the price of 1.5 missions gives one _both_ reliability and low cost.
The basic assumption here seems simple enough : everyone is free to do as the choose so long as they don't hamper or endanger the freedom of others.
However, just because one is free does not mean that one will make the decisions that will enable one to live the best life one possibly can, in some sense.
For instance, the Libertarian.org site discusses one application of the Libertarian philosophy : science and technology. They state that they feel that science and technology can do better without the "aid" (quotes theirs) of government.
This is a very curious position. The basic science and technology research which is pursued in our nation and others would be entirely impossible without large-scale funding from government agencies, which are ultimately supported by taxation. If directly asked whether they would support most science endeavors through personal donations, most citizens would flatly refuse -- they simply don't enough about the research fields involved. Even _scientists_ have difficulty deciding which projects should be funded -- hence the need for peer-reviewed funding agencies like NSF, NIST, NASA, etc. Yet, one cannot deny the huge impact which such research has had on our lives -- basical medical advances, fundamental knowledge of the universe, semiconductor technologies -- all would be impossible without the basic and applied research pursued by government.
The biggest payoff of one such gamble was the DARPA project funded in the late 1960s that would eventually flourish into the internet we know today. Under the Liberterian ideals espoused, the internet would not exist today.
In a nutshell, every individual simply does _not_ know what is best for themselves. The massive amounts of knowledge and technical know-how are distributed throughout the members of our society, and it is sheer hubris to think that any individual can make basic research decisions (in effect, by donations) better than the collective of all scientists and technologists in the nation. It is true that one sacrifices some amount of freedom by willingly supporting their decisions through taxation, but in exchange one receives all of the knowledge, and technical and medical advances which our society has received by supporting basic and applied research on large scales.
Libertertian.org is here today because of definitively non-Liberterian principles.
Bob
This sounds like a technological urban legend to me.
Note that radio frequencies are in the MILLIONS of cycles per second, wheras acoustic frequencies are TENS to THOUSANDS. The resultant frequency modulations would be almost entirely imperceptible on the scale of the FM band, over many MHz. Indeed, the way modern radio systems encode and decode the signal is through the use of heterodyne techniques; the signal is essentially detected as interference "beats" against a standard frequency reference.
Best,
Bob
Many people, including Jon here, have used the argument that since CD sales have been on the rise over the last severl years, there is no evidence for damage done by mp3-swapping.
Note however, that there are a myriad of causes for this growth (including the overall growth in the economy), and simply looking at net sales will not disentangle the causes. The question is not whether CD sales have increased, but what is the net effect of mp3-swapping on this growth? The answer is not obvious, since broadband net access is still only enjoyed by a minority, and so the effect of mp3-swapping is still insignificant in comparison to total sales. However, as more and more home users get broadband access, we can expect this effect to become very significant.
My own opinion is that the current effect of mp3-swapping is small and negative, but we can expect it to grow to enormous proportions in ten years or less, as the recording industry continues to fight a losing war.
Bob
This model will probably come to pass, but this company will not be the one to do it.
.25, since that will hurt their CD sales. Expect $1 - $2/ track charges. Their monopoloy on the licensing of the songs will allow them to do this.
Legally, they will get nailed, just as mp3.com already has (for Beam-It) and Napster will be. Quite simply, they don't own any of the licenses for the music they are trafficking in, much less the users who have simply ripped a few tracks from a CD they own. What legal rights does a pirate have for compensation for his pirated works? Nada.
Postulate. The RIAA companies will initiate such a service soon, after Napster and its competitors have been shut down.
The genie is out of the bottle with regards to mp3 files. No amount of interference can stop the illegal trade of mp3 files amongst users. The best the RIAA companies can do is to act as a middleman. People will be willing to pay a premium to have the service of a Napster-like central repository. Anyone who has used both Napster and Gnutella has realized that Napster's central sercer system is the way to go here in terms of speedy searches, and is superior to Gnutella for the trade of mp3 files. People will be willing to pay a small amount for that service.
The inevitable conclusion is that the RIAA companies may eventually act as middleman between users trading mp3 files. However, they will not offer microcharges as small as
However, mp3.com has purchased liscensing agreements recently with members of the RIAA (Warner, BMG) for its 'Beam-It' tool. The RIAA and its members DO NOT want to see mp3.com shut down, since 'Beam-It' presents just about the best opportunity for them to offer positive incentives to purchase more CDs while still protecting their property rights.
This is the real world, and the real world is not clean : mp3.com works with both the RIAA and independent artists. If you are really bent on sticking to principles, you should ban mp3.com as well. However, a more moderate stance is that we need both moderates and extremists pushing from both sides to really advance.
Bob
What was interest about this (to me at least) was just how _long_ ago most of the inductees had done their work. The Yahoo article mentioned that Helen Free and Woz were the only two living awardees out of seven. Most of the work was done in the 1940s...
;-)
Also, when flipping through a few of the list of previous awardees, you begin to sense just how ancient the patent office seems. Almost all were for some type of gadget.
Will we see Jeff Bezos and Amazon inducted into the hall in 2060 for patents which changed the way the web worked?
Bob
DGregory :
As I see it, accreditation is not the most important issue. The issue is how you are viewed in the eyes of others. Hence, if this program survives for several years, and is able to graduate top notch people with some incredible talent, then it won't take long for employers to identify ArsDigita U backgrounds just as employers identify people with Caltech, Berkeley, M.I.T., Stanford, etc. backgrounds. Every institution must
start somewhere, and I would argue that the quality of graduates is actually far more important than a piece of paper hanging in the administratives offices in a university hall.
With regards to social life, ask anyone who got a B.S. from Caltech or M.I.T. what kind of social life they had for four years. 12 hours a day, 7 days a week, is being conservative. And that was for four years, not one...
Bob
The solar constant at the location of the earth (luminosity of sun / (4 pi distance_from_sun_to_earth^2) ) is 1370 w / m^2. Let's be generous, assume the collecting area is 1 m^2. Let's also call things roughly. Per hour, that translates into (3600 s) (1 KW /m^2) 1 m^2 ~4 10^6 J. Let's say that a solar cell can have an efficiency of about 1%. That translates into 4 10^4 J = 40 KJ of energy.
How much energy does a typical battery store? State of the art chemical batteries typically have energy densities of 1 KWh / kg, or roughly 10^6 J/ kg, as above. This means that to charge a 1 kg battery, roughly 100 hours are required.
Even if the efficiency were as high as 10%, about 10 hours would be required to charge. Hence, it seems that the concept is good, but it would take at least a full day in sunlight to charge up a laptop battery. Not very practical, considering that the very idea of a laptop is to be mobile...
This story reminds me of an occassion when Richard Feynman was giving an informal talk at the Esalen Institute, a new-agey institute on the California coast between Los Angeles and San Francisco that he was known to frequent.
He was explaining the properties of matter (comparing atoms vibrating in a lattice to band members marching in step), when a guy from the audience interrupted and starting asking about antigravity devices.
Feynman, in his typical blunt manner, said something to the effect of, "Fella, what you are talking about is impossible. It violates fundamental principles of physics. What _is_ a great antigravity device is that seat under your butt."
I have to disagree with Zach on a couple of points.
First, I think that as a matter of principle, freedom of speech should allow one to profess whatever notions or beliefs that one cares to express. It is not the role of higher authorities and institutions to judge the validity of those beliefs, but rather the free marketplace of ideas. The Church's use of a house arrest, no matter how benign, is in fact an instance of state repression of personal expression, and is quite in conflict with the principle of freedom of speech. Of course, this is a modern notion, and we should acknowledge that the very concept of such freedom didn't exist in the 17th century. However, this does not justify the Catholic Church's actions in any fashion.
Second, I think that the key point of Sagan's books and videos is that they tried to instill the notion of rational skepticism in their respective audiences. In a world filled with pseudo-scientific garbage (astrology, Scientology, etc.) such voices are very desperately needed. The minds and hearts of future voters and taxpayers are at stake, and it is critical that we demonstrate the worth of rational thinking in evaluating ideas to them.