SkepticLance

Actually, the first life was neither animal or plant. The dichotomy of animal/plant does NOT cover all life forms. It is better to leave all Bacteria and Archaeans out of that classification. Yet they are life, and they precede both animals and plants in that they arose earlier in evolution than either.

I continue to be assailed by non logic! Other suicide methods are not relevent to the discussion. There are, of course, lots of ways of topping yourself, including bizarre ones like toilet paper. I was told that in WWII, certain spies were taught that they could kill themselves by biting their tongues half off and inhaling the torrent of blood. That was reasonably reliable, even when they were bound hand and foot. However, all that has nothing to do with the discussion. The question is : Is the ready availability of firearms a substantial contributor to the incidence of successful suicide? Fact : in 2001, 16,000 Americans killed themselves with firearms. Fact : Attempts at suicide with firearms are 90% successful. Fact : According to Canadian Medical Assn. Journal and New England Journal of Medicine, the presense of firearms in the home add to likelihood of successful suicide by 2 to 5 fold. Fact : Of all modern western nations, the USA has the highest per capita rate of suicide. Quoting non-western rates of suicide is comparing apples and bananas. How can anyone try to deny that availability of firearms adds very substantially to probability of successful suicide?

To Sayonara First Thank you for the gracious capitulation on the first point. I always admire people who can do that, far more than the more common variety of human irk who cannot ever admit barking up the wrong tree. Good for you! Second - re H bombs. You are correct in saying that an H bomb blast in or on a Dyson sphere would be trivial relative to the entire structure. It would still kill millions of people, though, and the inhabitants might not consider that trivial. So the answer depends on whether you are talking relative damage to the sphere or absolute damage in millions of deaths. Third - anti-matter bombs. Perhaps I have not made my point very clear. I think that speculation is fine if it sticks to what might be possible in theory. If something is totally impossible according to currently understood science, I think that kind of speculation is inappropriate to this forum. If you have anti-matter, then making a bomb is dead easy. The problem is getting the anti-matter in the first place. Currently we make it in accelerators an atom at a time. Could a future civilisation make enough (or find a source somewhere else) to make a bomb? Actually, I don't know. It is possible in theory, though, which makes it a candidate for speculation. Fourth - is a Dyson sphere possible to move? I could be wrong. However, I think this 'possibility' is very tenuous. You talk about moving a Dyson sphere. It would mass as much or more than our entire solar system. Have you calculated how much reaction mass you would have to eject to send it moving one way? And the same again to stop its movement relative to the sun? The only practical way I could see anyone moving a Dyson sphere, even to a very minor extent is to use 'the physics of the impossible' which puts it outside the defined area of speculation. Fifth - poo-pooing Arthur C Clarke Please do not misunderstand me. I admire his work. I have read most of his novels and enjoyed them. However, I have a very clear picture in mind of the difference between fiction and fact. I read fiction with great pleasure, and on the science forum I discuss fact (or speculations hopefully based on fact). Finally I agree with your last paragraph. Cheers.

Swansont said "I don't see how you draw that conclusion from the information presented. The warming is more than from GHG emissions, but that's not the only thing that affects temperature" Swansont You have been involved in this debate for a long time. You should know by now that my explanation for why GCMs do not always get it right is the unknowns that crop up. GCM's underpredicted Arctic sea ice melt, and one explanation is an oceanic current that was not previously seen. They predicted Antarctic warming, whereas it cooled (over most of the continent) due to wind movements (one explanation) that were not expected. In this example, an underprediction of Europe warming is now explained by aerosol reduction. In every case, something unknown changes the outcome, making the GCM prediction invalid. I continue to maintain that we cannot trust model predictions (or modelling of future outcomes, as iNow would insist) for the same reason. There will likely be unknown factors altering outcomes in unpredictable directions for some time to come. We have no way to know what all oceanic currents are doing, or how the sun will fluctuate, or what volcanoes will erupt. Every unknown alters outcomes. For this reason, models will continue to be unreliable in relation to what happens in the future.

Bumf said "I doubt that the wearing of clothing would be the only reason why man's ancestors lost their fur. " It is not the only reason. In any evolutionary development like this, we have to look at two sides to the change. 1. What is the adaptive advantage of the change? 2. How does the organism overcome the adaptive disadvantage of the change? For loss of fur, there are two main adaptive advantages often suggested - improved cooling, and improved resistance to parasites. However, that does not answer the question as to why human are the only terrestrial mammal in our size range to go furless. The reason other mammals have not is that they cannot meet point (2) - they cannot overcome the selective disadvantage of going furless. And that disadvantage is, of course, loss of thermal protection, which we get with clothing.

In exactly the same way you ignore the references I post from reputable sources. Still, it's nice to see consistency.

To doG I repeat. You comments about ropes, hanging etc are red herrings. The debate is about firearms. On the business of telling the USA how to run its laws. Again, irrelevent. This is a debate between people on a forum. It has no power beyond that. Debate subjects are pretty much unlimited, as long as we refrain from obvious pathologies such as ad hom attacks and obscenities. Within the topic, there is nothing to stop me saying that a certain set of actions is desirable. I have been saying that gun control is desirable, including the restriction of access to hand-guns. This is true for all countries. Mine, yours, and others. To cellbioS The total number of firearms suicides in the USA in 2001 was more than 16,000. http://library.med.utah.edu/WebPath/TUTORIAL/GUNS/GUNSTAT.html I thinks 90% of 16,000 is statistically significant!

iNow I do not know if you did the research yourself, or used someone else's. If you did it yourself, it must have taken you hours. That is why I said congratulations. It was an acknowledgement of the time and effort involved. I cannot afford the time myself to do full justice to all your references, since I have work to do. Thus I must confine myself to general comments. First; Modellers have been working on global climate models for more than 20 years. There has been a long series of such models, each a bit better than the earlier one. Each time, they tweak the models to make them closer to historical trends. They have reached the stage where they are approaching a close similarity with those trends. If that were not so, we would have to throw our hands up in horror and say what utter morons modellers must be. However, there is a very big difference between managing to tweak a model till it comes close to 20:20 hindsight, and actually modelling (or predicting) the future. The references I have been posting have been discussing that. The latest one (New Scientist) showed that models missed out on predicting, simulating, modelling what is happening in Europe. I have previously showed the same for predictions of Arctic warming and ice melting, and for the lack of ability to use cloud formation correctly. Second : Without taking the time to go through each and every one of your references, it seems to me that many consist of modellers and global warming climatologists telling modellers and global warming climatologists what a good job they have been doing.

To CDarwin This is one of a number of threads that are purely speculation. Speculating is a fun activity, even if it leads frequently to untruths. Not a problem if no-one can prove those speculations wrong, as in this thread. Personally, I am going to enjoy myself with these unproveable speculations, and stop when real and contrary data appears. If you try to curtail the speculating with demands for evidence, you are being a kill-joy and acting against a harmless and pleasurable debate.

To iNow Congratulations. That was a very good rebuttal. Wrong, but still good. Sadly I do not have the time to go through all your references, just as it is clear you have not made the time to read mine. It is also true that accuracy of models as assessed by the modellers is somewhat suspect. And this is essentially what you are posting. I am showing specific details of model inaccuracies, and these are genuine and correct, regardless of what the IPCC people say about IPCC models.

From doG "Again you can't support that. Lithuania has the highest suicide rate in the world and has tough gun control laws. Belarus is number 2." All of which is irrelevent. There are two things required to cause a suicide. 1. Most important. The desire to kill yourself. 2. The means. There are many places with high suicide rates, due to the fact that item 1. above is the big factor. In other words, lots more people want to kill themselves. Item 2. is what determines the success rate of suicide attempts. What I have been talking about is the percentage of successful suicides. If there are 100 attempts in Belarus, and only 20% are successful due to lack of access to guns, while at the same time in the USA there are 10 attempts and 90% are successful due to having guns, then Belarus will still have the higher suicide rate. Yet the widespread ownership of guns in the USA will be contributing to an elevated suicide rate, as I have been saying. And again, you have ignored the important evidence I supplied, from eminent medical journals. Evading the data will not make it go away. OK. Let me change the wording on my earlier statement, where I said the sole purpose of handguns is killing people. New wording : Handguns are designed specifically for killing people. The fact that a policeman can use it as a deterrent comes from the fact that it is designed to kill people. I do not have a problem with a policeman having a hand gun. I have a big problem with hand guns being available to all and sundry. Many people will be responsible gun owners, but lots of others will leave them unsecured, where children, burglars and would-be suicides can get hold of them. Re liberty. You are ignoring the fact that our liberty is curtailed anyway. It has to be. The classic example, as I described before is drink driving. The ban is a curtailment of liberty, but is the proper way to go. Similarly, there are laws stopping me beating my wife. Do you think those laws should be rescinded so that I can have the freedom to beat her up? Of course not. It is right and proper that some liberties are restricted, for the betterment of society as a whole. Gun control fits that category.

We have a number of contributors to this forum for whom English is a second language. Those people often misspell or use poor grammar. They have my total admiration. Their science is often excellent. Their English is adequate, and a damn sight better than any foreign tongue I possess! And their courage is admirable. To all you guys with a different mother tongue, forget the mistakes in spelling and grammar and keep those valuable contributions coming!

Spending time in water does not require hair loss. Seals and otters have the most amazing fur coats. Evolution for an aquatic existence did not lead to them losing hair. Quite the reverse. They evolved fur that traps air - much denser. Human hair loss is much more easily explained. We have had clothing for a long time. Development of clothing permits heat retention without having fur. And by being able to shed clothing, and having no fur, we can hunt with the major advantage over other animals of superior cooling. As I pointed out earlier, this gives hunting stamina that is extraordinarily superior.

Sayonara said : "Even if we do assume that this hypothetical civilization has found a way to mass produce antimatter bombs, you are still talking about a preposterous amount of antimatter need to actually do any serious damage to the sphere." The discussion of relative security stems from a comment made earlier by Reaper about that. I was pointing out that a big target is actually less secure than a smaller one, and that mobility is also a defense. However, that is getting sidetracked. I suggest we leave the security question, as it is really unimportant. We all know that, if there is a nasty bastard who want to kill people, there is no 100% security. Re Clarkes Law. Yes, I am familiar with it. You should remember that Clarke was a scifi writer. His laws are also scifi. They are as much science as Asimov's laws of robotics. Which is to say : not at all. We are supposed to be discussing science. I am happy to speculate, which can be a lot of fun. But I think we should limit our speculations to science. That is : we should not assume future sciences that can do what is now impossible, even in theory. My original point is that I doubt we will ever build a Dyson sphere. And we do not need to. As has already been pointed out, they are not necessary for Type II civilisations. In fact, if future development follows the Dyson swarm idea, there will be space for even more people than you can fit into a Dyson sphere. The swarm is essentially unlimited in number. The only limit is matter and energy resources. And a mobile habitat can access energy sources other than solar.

To doG I have ignored hanging because it is irrelevent to the discussion. I also ignored seppuku. Slitting open your gut and then having your head cut off has a remarkably high success rate in killing yourself also! However, it has nothing to do with the question of whether or not a high rate of gun ownership leads to a higher rate of successful suicides. Which it does. Arguing about hanging is a red herring. A tactic designed to distract attention from the main point without actually making any valid arguments. I should also ask you why you ignore my very good data proving my case? And in relation to your query about having the liberty to own guns, I have 2 points. 1. I have no problem with you owning guns as I have made clear earlier. I am saying that is sheer bloody insanity to allow people to own guns that are designed for nothing else except killing people. Would you want to own an AK47? It's sole function is killing people. Ditto for handguns. If you want, as a responsible adult, to own a hunting rifle, because you have a genuine need to use it for hunting, then there is no argument. If you want to own a gun that has no function other than killing people, then there is something seriously wrong! 2. On certain matters, liberty has to be curtailed. It is a relative value - not an absolute. No-one argues that we should stop people drink/driving. If I get plastered and drive my car down the freeway, the cops will stop me and I will end up in jail. And that would be my own damn fault. In exactly the same way, preventing people from owning weaponry that is designed purely to kill people is a sane and sensible restriction on your liberty. Bombs are also designed to kill people. Do you insist on your rights as a free person to own bombs?

To doG, who said "The truth is that the U.S. has one of the highest gun ownership populations of the world and yet it is not even in the top 10 in the world in rates of suicide per capita." That is like the comparison with Japan. Logic that involves comparing apples with cucumbers is not logic. If you wish to compare USA suicide rates, you must do it with a similar nation. And no-one has commented on the Canadian Medical Assn. report, which said : "Positive correlations were obtained between the rates of household gun ownership and the national rates of homicide and suicide as well as the proportions of homicides and suicides committed with a gun. There was no negative correlation between the rates of ownership and the rates of homicide and suicide committed by other means;" I think the data is strong enough to conclude with a high probability of correctness, that possession of guns in large numbers correlates with high rates of successful suicide. It makes sense in logic, and the data supports the conclusion. I understand that those poeple who has an emotional need to own guns will object to my argument. However, I would ask them to step outside their own emotional bias, and look at this logically and use the data. Here is a little additional data. An article from the New England Journal of Medicine, which is one of the world's most reputable peer reviewed medical journals. http://content.nejm.org/cgi/content/abstract/327/7/467 Here is their conclusion : "CONCLUSIONS. Ready availability of firearms is associated with an increased risk of suicide in the home. Owners of firearms should weigh their reasons for keeping a gun in the home against the possibility that it might someday be used in a suicide."

Sayonara said "Habitats could not move out of the way of flares" Solar flares consist of hot ionised gas rushing out from the sun. They have to cover 150 million kilometers to get to Earth orbit, which takes quite a while. Warning travels at the speed of light, and even with today's technology, we get warning 20 to 48 hours ahead of a flare. In our Dyson swarm civilisation, we can expect even more than that, and a chance for habitats to move out of the way. If that is insufficient time, then there is no reason for the habitats to swarm at 1 AU. They could orbit further out and get more warning. This would even permit more habitats in orbit. It would be easy for an advanced technology to compensate for lower energy flux with more collectors. Sayonara also said "An H-bomb attack might do serious damage to a habitat, but not a sphere. " This statement is based on the missile hypothesis, and is used today by the military as an excuse to spend megabucks on developing anti-missile defenses. If I were a terrorist wanting to explode an H bomb in Washington, I would not deliver it by missile. My delivery vehicle would be a battered old Volkswagon Kombi van. If an H bomb attack were planned against a Dyson sphere, the individuals perpetrating that atrocity would get more impact by dismantling the bomb and reassembling it inside the sphere. It would do serious damage all right. In fact, it is worse than that. A highly advanced technology would likely have anti-matter bombs! Also said by Sayonara ""I can't imagine the technology responsible for building such a structure ever doing it well" is not an objection." The problem is that if you carry that view into a science discussion, you end up discussing science fiction, or even fantasy. If something is theoretically impossible today, we cannot simply assume that advanced physics will find a 'magical' way to do it tomorrow. I think it is valid to postulate advanced technologies that are marginally possible in theory only. However, to postulate advanced technologies which are theoreticaly impossible by today's understanding .....well why not postulate a magic wand while you are at it.

The last few posts indicate the tendency for those who dislike my more sceptical approach to ignore most of what is said, and focus on, and distort what they can be bothered reading. The primary part of my post (#200) was about a reference in New Scientist to the fact that the computer models missed the mark in Europe. Another example to show how unreliable they are. Instead, I saw my debate opponents ignoring the main point and focusing on a throw-away remark about weather variation. Is this because they are unable to respond to the main point? Ho hum.

Carrying water is not that difficult. The San people of the Kalahari used to do it using the shell of an ostrich egg. The Maori people of my country used the dried shell of the gourd fruit, which I believe is also widespread in Africa. In the Pacific they used coconut shells. There are probably lots of other ways that I do not know about.

The Japan data point is actually irrelevent to the argument. All it shows is that cultural values are also important. Japan has had a long history of using suicide as a means of solving problems. Whereas the West has tended to regard suicide as a cowards way of opting out of your problems (and I know that is not true, but I am talking about attitudes), Japan has had for many centuries the cultural value that suicide is the ultimate apology - an honourable way of telling the world that you are sorry for your failures. Suicides are regarded in Japan as people with honour, compared to the West regarding them as ultimate failures. The closest comparison that actually makes sense to the USA is Canada, since it has a culture that is similar (don't kill me you Canadians! I know there are also many differences). The US has more than 3 times the gun ownership per capita compared to Canada and about twice the suicide rate. http://www.cmaj.ca/cgi/content/abstract/148/10/1721 Here is the abstract for this paper from the Canadian Medical Assn. Journal. "To examine international correlations between reported rates of household gun ownership and rates of homicide and suicide with a gun. DESIGN: Survey. POPULATION: People who responded to a telephone survey conducted by the 1989 International Crime Survey in 11 European countries, Australia, Canada and the United States. RESULTS: Positive correlations were obtained between the rates of household gun ownership and the national rates of homicide and suicide as well as the proportions of homicides and suicides committed with a gun. There was no negative correlation between the rates of ownership and the rates of homicide and suicide committed by other means; this indicated that the other means were not used to "compensate" for the absence of guns in countries with a lower rate of gun ownership. CONCLUSION: Larger studies are needed to examine more closely possible confounding factors such as the national tendency toward violent solutions, and more information on the type and availability of guns will be helpful in future studies. Nevertheless, the correlations detected in this study suggest that the presence of a gun in the home increases the likelihood of homicide or suicide. " In other words, the hard data shows that more guns means more successful suicides.

To Reaper There is no such thing as a minor adjustment to something as massive as a Dyson sphere. Imagine the sun spits out a massive flare (there is no such thing as a 100% stable star) and the force moves the sphere off centre by a few cm per second velocity. Now you have to stop its movement relative to the parent star. How are you going to do that? You suggest I do not like the Dyson sphere/swarm idea? Actually, I am neutral to either option emotionally. However, I like to look at the practical realities, in the light of modern science. Sayonara suggests that physics will change massively. Perhaps. But for the purposes of debate within this forum, it behooves us to stick to what is known. Otherwise we are writing fantasy. From the practical viewpoint, in the light of known physics, I cannot see a Dyson sphere being practically possible. However, a Dyson swarm is eminently possible. I also think it is a more secure way of life. A Dyson sphere is very vulnerable to disaster - both natural such as an exceptionally large stellar flare, or manmade such as an H bomb attack. A Dyson swarm is much less vulnerable to both due to the ability to move habitats and get out of the way of the problem. Anyway, if we regard a Dyson swarm as a Type II civilisation, we should be able to calculate how long it would take. Due to the mobility of habitats, it will happen simultaneously around many suns. Possibly around each and every star in our galaxy. If we assume that a space habitat can travel at 0.1 c, which is possible theoretically based on current physics, then a trip to the opposite end of the galaxy will take 700,000 years. Human reproduction is quite fast enough to over-populate the entire galaxy in less time than that. Thus, the time taken to set up Type II civilisation (Dyson swarms) around all the suns in our galaxy, and using conservative assumptions, will be somewhere between 1 and 10 million years. PS - I realise that this future civilisation is not really a Type II, and in some ways is approaching Type III - but if you assume my model of Dyson swarms and travelling space habitats is real, then it is probable that progress will not go I to II to III, but will do all three kind of simultaneously. In other words, the distinction loses meaning.

Sayonara suggested "Are we are pretty much agreed that: (a) if someone wants to kill themselves, they are not going to change their mind just because they do not have a handgun within reach, (b) having a handgun within reach does not make people intent on doing themselves in, and © handguns might well make for a more effective means of topping oneself, but this is beside the point." I will rephrase these three points (purely for argument sake). (a) If someone wants to kill themselves and use something other than a firearm, they are much more likely to survive. If they decide to try for a drug overdose, they have 45 times the chance of surviving. (b) Having a handgun available does not change suicide intent - true. © handguns make a more effective means of topping oneself, and this is exactly the point. If we want would-be suicides to fail, and continue living, then it is best not to have handguns available. iNow claims we have too little data. iNow, did you read the earlier reference ... http://www.guncontrol.ca/Content/TheCaseForGunControl.html "Homicide of a family member is 2.7 times more likely to occur in a home with a firearm than in homes without guns. Keeping one or more firearms was associated with a 4.8 fold increased risk of suicide in the home." Plus a whole lot more data showing clearly that more guns means more suicides and more homicides.

Sayonara said : "Well, you are saying one or the other of two things here. Either... 1) It's impossible to build a solid Dyson sphere because it cannot be moved to compensate for the star's motion, or" Actually, I think I overstated a position in my previous post. I should say sorry for that before continuing. Sorry. My comment about the Dyson sphere is that it would be really, really difficult to move it as needed. A Dyson sphere would have to be of a mass that is truly astronomical. At least that of our entire solar system (excluding the sun). To figure out a way of moving that mass, even to the most minor degree, would be essentially not possible based on our current understanding of physics. Indeed, if you were able to push the sphere at one point by, say, a million kilometres, the response elsewhere in the sphere would be largely to stay put while the sphere deformed to a very minor extent. How to move an entire sphere weighing as much or more than our solar system is a problem that has no current solution, unless there is some breakthrough in physics beyond our present understanding. My alternative suggestion - that civilisation will become dependent on space habitats powered by deuterium - has the advantage that it does not require any new and magical physics. In theory, it can be done using an extension of what we already know. The biggest difficulty will be making fusion power practical, and that should be achieved within the next 100 years. The amount of deuterium probably available in the cosmos should be sufficient to outlast the main sequence of suns in our galaxy. That statement is based on 2 assumptions. 1. Water elsewhere also contains about 1% of its hydrogen as deuterium. 2. There is as much water in other solar systems as in our own. I suspect these assumptions are very valid. In terms of social development, the concept of trillions of habitats permits a wide variety of social set ups. Each habitat might have a million plus people, and would be essentially an independent nation in its own right. While there would be trade, communication, and people swapping between habitats, each could still develop its own way of life, political philosophy, economic system etc. Any time a habitat nation decides its cannot live with its neighbours, it can just strap on its ion drive rockets, load up with reaction mass, and cruise off to another star system. Perhaps humanity's distant future will involve a truly astronomical number of habitats cruising between the galaxy's solar systems, with vast numbers forming Dyson swarms around popular stars. Sayonara said : "What I don't get is why he thinks that while the enclosed star travels around the core along with all the rest of the matter in the galaxy, the Dyson shell is going to maintain an absolute position in space. But that has nothing to do with this thread, so meh." Obviously both star and sphere are going to travel in the same direction at approximately the same velocity. It is the approximately bit that is the kicker. There is no physical connection between star and sphere, and thus they travel independently. We are talking about a structure that is designed to last a million years plus. There will be small differences in direction and velocity that will mean the relative positions will change. Given enough time - disaster!

Sayonara said : "But it's a trivial and contrived objection: clearly an effort to build any such structure would take that problem into account, so it will never physically arise." I could not disagree more. This is the science forum. If we see something implied that is essentially contrary to the laws of physics, then it should be mentioned. And to assume that an advanced civilisation will magically find a way to get around those laws is a complete cop out. If we assume 'Dyson sphere' equals 'Dyson swarm' then we have a solution that does not go counter to the laws of physics. Perhps we should follow that line.

Another example of global warming predictions missing the mark. http://environment.newscientist.com/channel/earth/climate-change/mg19926634.800-cleaned-up-skies-explain-surprise-rate-of-warming.html?feedId=climate-change_rss20 "Since 1980, average air temperatures in Europe have risen 1 °C: much more than expected from greenhouse-gas warming alone" Here in New Zealand, over the past few days, we have had the biggest snow dump for about 20 years. It has been incredibly cold! Brrrr. In the town of Christchurch, snow down to sea level which is almost unheard of. Just another example of a normal weather fluctuation that has nothing to do with global warming. Another indicator that the global oven fanatics so frequently exaggerate the impact of global warming.