the asinine cretin

Trolling? How dare you mock the craft. I am an artist, sir.

http://www.youtube.com/watch?v=r4p8qxGbpOk

That actually doesn't matter at all to what I was saying. You've clearly not understood me. I didn't mean to say that such is your view and I'm glad to hear that it isn't. In my mind you've had the benefit of the doubt. No need to be defensive. I don't agree. But fine. Shall I actually take the time to further clarify where I'm coming from or will you just reply with a series of pithy complaints and then declare the conversion void? I don't know how you got that reading exactly. The reason I posted it is that it elucidates a view I share on the subject of intrinsic methodological naturalism. Consider the first paragraph of the conclusion. "In this paper, we reviewed five arguments in favour of the conception of MN [methodological naturalism] as an intrinsic property of science (IMN), and we found them all wanting: the argument from the definition of science, the argument from lawful regularity, the science stopper argument, the argument from procedural necessity, and the testability argument. Instead, we defended MN as a provisory and empirically grounded commitment of scientists to naturalistic causes and explanations, which is in principle revocable by overwhelming and unmistakable empirical evidence (PMN). Evolutionary scientists are on firmer ground if they discard supernatural explanations on purely evidential grounds, and not by philosophical fiat." Rather than glean favorite quotes I'd just suggest rereading it. It is not an "argument against supernatural things being approachable by science." It's more interesting than that, in my opinion. Regards, sir.

What my imaginary creationist friend is saying: No, breeding is just microevolution. Nobody denies that. But you'll never see a dog turn into a non-dog. Darwinism claims that man came from a microbe. That's a faith-based position as we've never observed kinds becoming different kinds. What else ya got? Humans are an intelligent designer. Therefore, as far as we know evolution can't happen without an intervening intelligence. I don't share your "faith" in random chance. Zing! P.S. Giving me the -1 isn't going to justify your RELIGION! Admit that you believe in Darwinism because you happened to be born in a country that indoctrinates its youth in this RELIGION! There are other interpretations. The fossils say NOOOO!!

Consider this addendum to my last post. I've been reading Maarten Boudry's essays recently. Good stuff. How not to attack Intelligent Design Creationism: Philosophical misconceptions about Methodological Naturalism (See more papers in "Writings" section of nav.)

I don't agree with your assessment (cynically restating what I've already said or alluded to as though a new insight is correction? --I call it obnoxious) and I find your use of the mod tags in sharing your feelings to be worthy of contempt. Am I supposed to be threatened? Fortunately I have a life outside of this website. EDIT: Okay, in honor of Wil Wheaton and in the name of Sybok, I hereby swallow my pride and renounce my uncivilized behavior on this thread. I'd like to thank you, swansont, for your fraternal correction, and I do so from the depths of my heart. D H, I must commend you for suffering my foolish behavior and I resolve to treat you with the utmost respect from here on out. I'd also like to thank you for your insightful commentary on my own imbecilic posts; I very much appreciate your time. Best wishes, and God bless.

Thank you. Fair enough. I suppose there is a spectrum of credulity among religious believers, but I think it's fair to say that in general there are doctrines that must be believed in a fideistic manner. Some Christians draw the line at some of the miracle and seek to contrive natural explanations, some perhaps at the Virgin Birth, some are naturalists when it comes to everything but the Resurrection. Most of the Christians I've known accepted just about everything except perhaps the more fantastic fables of the Old Testament. Finally, I know that there are people who describe themselves as Christians who reject even the Resurrection (Bishop Spong?), but these seem to me to be a fringe minority and I don't really know what to make of them. As Saint Paul said, "if Christ be not risen, then is our preaching vain, and your faith is also vain." In other words, what's the point? I don't quite remember where I was going with this. I guess just that basic logic is sufficient to challenge or refute religious claims - and generally preferable. In my experience, the place for the philosophy of science discussion is in evaluating specific claims that can be addressed scientifically. Often paranormal claims are of this kind, while religious/theological claims seem often by nature to dodge that sphere of knowledge. Did Jesus rise from the dead? This is not necessarily falsifiable claim. It's a one-time historical event, which doesn't mean that it didn't happen. But might it be reasonable? We have the tools of historians and biblical scholars to put to use at least. Apologists/theologians have spilled a lot of ink arguing that it is plausible and that there are good reasons for entertaining it as a fact -- thereby being open the Holy Spirit and receiving the encounter with Christ, the gift of faith, and so on. Meh, whatever. Never mind.

To elaborate where I was coming from, there are many perfectly rational beliefs that are not scientific claims and that are not falsifiable. (Tangential, but I'm not as enthusiastic about naive falsificationism as I was when first reading Popper. For elaboration I would mention that I think Susan Haack has some interesting things to say in this lecture: ) As an example, the consensus among scholars that Jesus of Nazareth actually existed is a reasonable view that is not "scientific." Similarly, believing that Mohammed actually existed is perfectly rational, while believing that he flew on a magic donkey is not, and the reasons for this distinction are not mere falsifiability. While it's an important aspect of scientific methodology, and knowledge in general, to insist that falsifiability is what makes beliefs rational or irrational may warrant the scientism epithet. As an example (and in spite of "proofs" for the existence of God and the hyperbole of some apologists), Catholic doctrine does not assert that the existence of God is demonstrable in some scientific sense, but rather that there is sufficient reason for believing that there is a God. I think this is closer to the sense in which there is sufficient reason to hold that Julius Caesar actually existed, or that Paul of Tarsus existed, and not in the sense in which a scientific hypothesis is tested. (This sufficient reason then opens the door of the heart and mind to faith, which is a supernatural virtue and considered a gift of God, rather than something that can or should be completely justified on rational grounds. Within this framework is the necessity for, and validity of revelation.) Thus, I don't think that the demarcation problem, and the claim that something is "pseudoscience," is always applicable to religious claims. Is the important point with respect to the miracle of the loaves and the fishes that affirming it is "pseudoscience," or the more basic fact that believing in a miraculous event based on alleged testimony far removed from the actual events, and in a genre of literature unconcerned with historical fact, is not rational? Dammit. I'm not done but I've got to go.

Plug for Sean Carroll's book. From Eternity to Here: The Quest for the Ultimate Theory of Time

Here's what my imaginary creationist might say. 1. The algorithm that settles on S H A K E S P E A R E over many iterations of random character selection assumes a teleology. For us that teleology is explained by the Intelligent Designer and you've just illustrated the plainly evident signature of that Designer. You're blinded by Naturalism, Darwinism, and Atheist religion and therefore your darkened intellect refuses to see it. 2. Laboratory experiments show that natural selection has fitness costs and that Darwinism alone cannot account for fitness and new information. Therefore, we hypothesize that an Intelligent Designer is in some sense operating in nature to bring about a purposeful, and directed evolution of life - of course with humans at the top ready to know, love, and serve Him in this world in order to be happy with him in the next. Give up your faith in Random Chance and apprehend the presence of the Intelligent Designer. The Bible is true.

Of course. But the fact that we developed Po-210 RTGs in the late '50s makes me inclined to think you're exaggerating. Wikipedia mentions the half-life as the primary reason why Pu-238 was favored. And again, holy crap, no kidding the short half life means it's of limited use. Did I ever suggest otherwise? I thought I made that point pretty clear on multiple occasions. But really, my scenario was completely speculative and evolved to assume extensive space infrastructure. It's just a "what if" scenario so don't worry about it. Oh, and the more general point was not that Po-210 is a panacea, but that alternative isotopes may be worthwhile for particular applications. I picked Polonium as an example because I knew RTGs had been built using this element and BECAUSE of its short half-life; although there are nearly 30 radioisotopes considered to be candidates for RTG tech. This isn't a peer-reviewed journal it's an internet forum. Don't be a dick or I'm telling Wil Wheaton. Also, if you're going to be so condescending and presume to "peer-review" someone's speculative internet comments at least read what they fuckin' write and do more than restate things they've already said. I've already made that point. I guess I won't fault you for not picking up on it. I've had a tendency in this thread to start reading a doc, post about it, finish reading it, and then edit my post and append comments. That may be. I hope not. If you have evidence for this claim I'd be interested in seeing it.

I am not a scientist of evolution, psychology, and/or anthropology. Just an internet rando/ignoramus. My understanding: 1. Evolution by natural selection is not "random," and I suppose in the case of our ancestors the capacity to reason was a survival advantage. Hunting, tracking, cataloging useful plants and materials, making tools, planning for the future, et cetera. I think there also may have been a feedback with increased social complexity driving greater cognitive ability which in turn drives greater social complexity (hopefully I'm not bastardizing the idea; I recall reading about such things anyway). 2. The scientific method and being logical are not innate but require training and discipline (I think these are more cultural artifacts than products of biological evolution). Our psychology has evolved with a great many flaws from this point of view and science was invented partly to mitigate human irrationality. Being off-the-cuff here, I suppose I see the emergence of scientific methodology as analogous to the emergence of a physical toolkit. But since you were hoping for educated opinion I'll just shut my yap. Cheers.

Interesting post, Enthalpy. What do you think of the SAFE-400 reactor? What do you think of Mars Semi-Direct, and other mission architectures inspired by Mars Direct? I'd love more information on the first thing you mentioned; namely, hydrogen + sunlight propulsion. How would that work and how did you arrive at the Isp numbers? Thanks The SAFE-400 operates at 100 kWe and 400 kWt, therefore, it would take 120 reactors. Sorry, self.

I wasn't speaking of simple belief in God. My sentiment was that belief in the fantastic stories of religious traditions is not within the realm of rational discourse. I will say that the leap from an altered state/religious experience to "therefore, my favorite religious text is true," is obviously not valid. I suspect even people who believe that they experience a divine being in their lives can see that. I think the gist is that people aren't particularly reasonable and that cognitive bias reigns. If a person can see that their pet supernatural/paranormal claims are of the same general kind as those made by psychics, UFO abductees, and people of other religions often with contradictory religious experience, they may face the fact that purely subjective data and a hopelessly self-referential worldview do not constitute a means of honestly understanding reality. There are mountains of reasons for seriously doubting each of the world religions. There are also many reasons for doubting the supernatural character of religious experience. This is in some ways acknowledged by some religious traditions. For example, some writings advise paying no attention to apparitions and other "extraordinary phenomena" because they may be demonic or self deceptions. Given what we now know about hallucinations, self-deception, the ease with which the mind can generate feelings such as awe, a presence, and the like, one would be irrational not to doubt even the most vivid supernatural "experiences" that could not be objectively verified in some way, which seems to be all of them. But sure, there aren't many who have the self-honesty and intellectual integrity to genuinely explore the undesirable possibilities. P.S. I say this as one partial to the possibility of the supernatural. P.P.S. I've just gotta give a shout out to bdwilson1000's video intro to the .

In that case I don't think you even need to get into the demarcation problem. One is a substantiated, if provisional, claim based on empirical data (i.e., the inference of the approximate number of baryons in the observable universe), the other is hardly different, epistemologically, from belief in the events documented in Gulliver's Travels. These things don't even enter the realm of rational discourse to begin with. Mohammed talks to beings from outer space (or some shit - whatever they think heaven is) and rides on a magic flying donkey? These are claims that some would want us to take seriously, and they'll dog on scientific insight to advance this petty cause? I can only laugh and cry. Oh, and not only are people supposed to take this seriously and believe, but this (the angel thing anyway) is the basis of one of the most prominent cultural phenomena in the world - namely, Islam. The Book of Mormon was magically received and written down, or translated; the Bible was "inspired" in some sense that even professional theologians have a hard time actually defining much less substantiating. (It seems to me that inspiration is basically a thought-terminating cliche among intelligent Christians and merely a superstition among fundamentalists.) And the like. Magical holy books in the 21st century? Societies dominated by the teachings of these ancient tales? How does this make any sense at all? Even if these books didn't reek of their human origins, what the heck? Who can explain this to me? Edit to add: Insofar as this is snide, I apologize. I'm not trying to be a dick. (Maybe it comes naturally.)

I have no experience with such things, but my guess is that rather than there being a biology programming language, there are libraries for existing languages. For example, a Google search just brought me to some python libraries. http://biopython.org/wiki/Biopython This page has a list of relevant python tools under the "Life Science" section. http://wiki.python.org/moin/NumericAndScientific I'm sure there are similar resources out there for other languages. I just searched for python because I've fiddled with SciPy. Is this helpful at all?

I don't follow. Forgive me, but, is this sincere inquiry, disingenuous obscurantism, or something else? Of course I don't "know" how many baryons there are. My understanding is that our best estimate indicates roughly 10^80 baryons in the observable universe. But who cares? What actual point are you trying to make with these rhetorical questions? Are you somehow trying to suggest that empirical estimates of this kind are comparable to belief in religious stories such as Mohammad talking to an angel or flying on the magic donkey? I must be misunderstanding your intent. Thanks for the reply.

At least with #2 you can look up the basis of the claim, and it doesn't claim to be anything more than our best estimate given certain assumptions. On the other hand, #1 is something out of the fairy tale genre that asks for your assent, no questions asked. If you're born in the wrong place/time that could be "assent, or else." P.S. I am aware of plausible estimates of the number of baryons in the observable universe. Such an estimate does not include dark matter or dark energy and I'm not so sure that your objection would be relevant. As far as the thread topic is concerned, I think some forms of religiosity are "broken" in the sense that they require certitude where there is none. I'm hesitant to say religion must include dogma and confident supernatural beliefs. There are many distinctions that can and should be made. For example, the kind of religious experience described by mystics of various traditions is quite different from the doctrinaire fundamentalism many Americans seem to espouse and promote. Love everyone, explore the depths of human consciousness, revere and in some sense worship the mystery of being, and so on. As opposed to, "the bible says the earth was created in six days, and by golly, if the king james bible was good enough for jeebus, it's good enough for me." Or the somewhat more sophisticated variant, "complexity, complexity, complexity, mouse traps, bacterial flagella, therefore, Jeebus." P.P.S. It's very hard to imagine, but I am open to the possibility that some version of one of the traditional religions is true. I haven't ruled out the supernatural a priori, or the idea of an intervening personal God, or of a pantheon of "divine" beings (whatever that even means), or of supreme extraterrestrial beings beyond our comprehension. The issues, at least to me, are epistemological and psychological. I am unaware of a viable religious epistemology/criteria of truth that could sufficiently test and justify religious claims. Second, I think that the psychology of belief and the study of religion as a natural phenomena go a long way toward an adequate explanation of existing religions as purely human constructs.

Interesting. I just googled "Unity Scripting" as mentioned in the video title. How does that work? I have some background with game development so I'm curious. Actually, the last game project I worked on was a space game - but I never finished it (just a hobby). The games I've done on my spare time (which was years ago when I was a bachelor), involved building out a rendering engine using C++ and a graphics library (last game engine I developed used DirectX 9.0c) as well as writing shaders (HLSL was hot at the time), and then creating, rigging, and to some extent animating meshes in a tool like 3ds Max. I used Photoshop for textures and things. I wrote custom software (rough software that wouldn't win any awards, to say the least) for integrating assets into scenes and "levels." Finally, what might be called scripting in my game was entirely proprietary and bare-bones. The scripting language was syntactically reminiscent of JavaScript but minimal and executed with an interpreter/engine of my own design. Oh, and then the rest of what goes into a game engine, the physics, audio, user input, et cetera. Not the most feasible solo project, especially considering the scale of the games I wanted. I've only glanced at the site, but Unity seems to be an IDE Of sorts that integrates a full-featured game engine, asset editor, world builder, and "store" for purchasing ready-made assets. If my impression is correct, wow. Maybe the old game development hobby is something I could pick up again. What do you think of Unity? Have you used other game dev technologies/approaches? Does it have good APIs that let you really hack things? Well, rather than bombard you with questions I suppose I could click around their site more and use Google. Having said all that, what is your game going to be like? Do you have it planned out in detail? Just curious. Peace.

In case anyone is interested. Electric Propulsion: Which One For My Spacecraft? Gas Core Nuclear Rocket Engines Promise and Reality Regarding Beamed Power Photovoltaic Receivers for Laser Beamed Power in Space Pulsed Laser Illumination of Photovoltaic Cells Beamed-Energy Propulsion Study (this doc is effin huge, be warned) NASA Technical Reports Server (search results) VASIMR Related Ad Astra Publications Nuclear Electric Rocket SAFE-400 Fission Engine (400 kW; 1.2x10^3 kg) Design and analysis of the SAFE-400 space fission reactor An Ad Astra study (found here) describes a mission using 12 MW VASIMR propulsion for a < 3 month trip to Mars and allocated about 25 mT of mass budget for the reactors (including radiators). It might then take 30 of the SAFE-400 reactors to achieve 12 MW. At 1200 kg each that's about 39 mT; significantly over budget. However, I suppose a megawatt-scale reactor would have a smaller specific mass. I wonder how the SAFE design would scale? What might the mass be for a 1 WM version, or a 6 MW version? (The SAFE-400 is basically the result of some fiddling "on the side" with discretionary money; it's not unreasonable to suppose we could do better with serious funding.) The study also describes an epic 200 MW Mars mission. This very interesting paper was among the references. Multimegawatt NEP with Vapor Core Reactor MHD

I hereby applaud and salute you. Thanks for the excellent info.

Hehe. Okay. +1 Would you be willing to do me a favor and +1 this post? http://www.scienceforums.net/topic/53264-ion-drive/page__view__findpost__p__679732 I was pissed off and clicked the -1 pretty impulsively.

I am aware of the current state of Pu-238 and the other things related to that covered in materials that I've posted in this thread. But I'd like to know how you can say that this is the main driver behind the push for ASRGs. I don't dispute that it's a driver, but you make a lot of claims like this that strike me as supposition. If you have sources for these claims please share, if not, please indicate that you're just speculating. Are you personally involved in any of these things? (I actually find it hard to believe that you don't understand the many advantages of ASRGs over RTGs.) Again, I'm inclined to dispute this. RTGs have their advantages, but ASRGs are significantly more efficient (even if Pu-238 production were still happening the fuel would be expensive, and radioisotopes are heavy, dangerous, et cetera), and based on what I've read you're wrong that ASRGs add more mass. Some of the sources I've provided state that ASRGs are lighter and that this is a real advantage (I'd actually like to learn more about this as these sources have not gone into detail). Again, if you have sources I'd like to see them. The basis of my impressions can be found in documents linked above. Where are you getting your numbers? The 2008 NASA Planetary Science Division Update indicates that the ASRG prototype has a nominal power of 140 W with 0.8 kg of Pu-238 fuel, but gives the mass as 20 kg, not 32 kg. I've also read that the 200 kW VASIMR can serve up 20 Newtons. But you're missing the key thing about my RTG/ASRG speculation, and why I brought it up at all, which was that Po-210 might be used, not Pu-238. This changes everything. And I'm interested in the theoretical potential here, not merely existing prototypes. E.g., Entertaining the possibility of fuel other than Pu-238 (the key point being that Po-210 ups things by orders of magnitude). A large ASRG utilizing 10 kg of Po-210 with 30% efficiency would obviously have very different specs than a 0.8 kg Pu-238 device, or multiple 140 W Pu devices that add up to similar power output. It's a fun theoretical exercise and not something I'm interesting in bickering with you about. Your condescension and habitual naysaying anger me. Thanks. That is interesting. Reading those links now. What I'm curious to know is to what extent such things are being actively developed right now. I mean, is this a possible solution for 100 years from now, 50 years from now, etc? It's encouraging to see ASRGs in the agenda-setting NASA docs, for example. (Disclaimer: What follows is purely "what if" speculation for its own sake and there is no need to take a shit on it. Assume I know the obvious. If you're offended by this, just consider it sci-fi or something. Thanks.) Bismuth might be obtained as a byproduct of mining and refining metals such as gold, silver, copper, cobalt, nickel, tin, etc. from asteroids. Such operations would presumably be established independent of the Polonium-210 fuel idea. Rather than having facilities on Mars it would probably make more sense to have the production capabilities on Phobos or Deimos. Perhaps one of these bodies is itself rich in relevant materials. A significant mining-refining operation on such a body would likely include a substantial nuclear reactor which could supply the neutrons. The production of short-lived but super high output Po-210 power source "refills" might then be a relatively painless byproduct of profit-driven infrastructure development. Basically, operations on Phobos receiving and processing materials from NMOs and asteroid belt objects; operations on Luna receiving and processing NEO materials; and a two-way express route powered by the Po byproducts. Of course if space operations were already that advanced the current topic of powering VASIMR and the like would be obsolete. Again, this is just a fun imaginary thing. But I do suspect that Po-210 will prove to be a useful fuel with a variety of applications in the future. The theoretical potential is interesting anyway. As far as the real topic of getting the VASIMR in operation in the near future, based on what I've read, the direction they seem to be going is solar power. Of course this limits the applications considerably. But I recall something about a 2 MW solar array with multijunction photovoltaics with greater than 30% efficiency. I don't know how accurate or current this information might be. And I'd be curious to know what kg per kW ratio they can achieve. Must continue Googling... Although, for the lunar cargo spacecraft, perhaps solar arrays in cis-lunar space could beam power to the craft via microwave, thus radically reducing the mass required by power systems. I've researched space-based solar power and the possible efficiency is actually very good, but the receivers tend to be huge and the distances involved are of course far less than would be required for a lunar-bound spacecraft. Maybe laser power beaming from cis-lunar arrays and/or a lunar surface array.It would be interesting to explore such concepts anyway. P.S. This site is fun. http://www.asterank.com/