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Comment: Re:I had the exact opposite experience (Score 4, Insightful) 285 285

by sasami (#41292241) Attached to: The Problems With Online Math Classes

Absolutely right. I have to correct this misconception regularly.

My lessons are never the same year to year because the students are never the same year to year. Sometimes the level of the class is higher or lower, but that's not where the greatest variation comes in. Instead, what you'll find is that this year's class will breeze through some topics that last year's class agonized over, and then utterly implode on topics that last year's class found easy. What's hard and what's easy varies constantly, almost randomly. It's mysterious, inevitable, exciting, and exhausting. Based on the peculiarities of each year's students, I spend as much time adjusting every lesson as I did preparing them originally. Sometimes, it even takes more time, if I have to restructure things in a way that affects many subsequent areas.

Comment: Re:No surprise?? I dunno (Score 1) 497 497

by sasami (#41290049) Attached to: Scientists Say Organic Food May Not Be Healthier For You

Organic doesn't mean "safe" -- a pesticide is a toxin and made to kill, regardless of what it is made of.

And it's very important to carry this reasoning to its logical conclusion: Which plants produce these killer toxins? All of them.

Plants do not want to be eaten. Plants avoid being eaten by being toxic, and most of them are very, very good at it. Natural pesticides are no less carcinogenic than synthetics (at least in rats), but "Americans eat about 1,500 mg of natural pesticides per person per day, which is about 10,000 times more than the 0.09 mg they consume of synthetic pesticide residues."

Failure to appreciate this fact has, at least once, led to the tragicomic result of "organic" produce being far more toxic than conventional. Celery produces some nasty irritants called psoralens, which are pretty effective at warding off insects. So some organic growers chose to plant "insect-resistant" celery that's been bred for high psoralen content. Too bad these varieties are human-resistant as well. Harvesters suffered severe rashes just from handling this stuff... but that's okay, it's natural!

What we call "vegetables" are simply those plants whose toxins we can digest in the quantities we normally eat. To a deer, poison ivy is a vegetable, but fiddleheads are deadly. In fact, even some humans can eat poison ivy, being naturally immune to the problematic substance, urushiol.

Comment: Re:But that is actually the point (Score 1) 583 583

by sasami (#35273426) Attached to: LotR Rewritten From a Mordor Perspective

If the premise of the book is simply an admonishment to be more thoughtful and skeptical with regard to history, that's quite commendable.

But it seems more that the premise of the book is to advocate the extreme (yet fashionable) idea that historical truth is impossible. That's not commendable, because it is nonsense.

Thus, the maxim "History is written by the winners" means something completely different depending on whether you believe the former or the latter. If the former -- the realist position -- then it means that historical truth exists but it must be carefully extracted from multiple biased viewpoints. If the latter -- the postmodern position -- then it means that historical truth doesn't exist at all, so every viewpoint is just as valid as any other. (That's no exaggeration. Consider historian E.P. Sander's opinion that "No historical events can be verified, even events that we have recorded on videotape.")

So when you say:

the entire premise is that the Lotr is a lie.

that doesn't tell me quite enough about this book. Is Eskov's premise that LotR is contains many lies and must be examined, or is it that all histories are nothing but lies and you can therefore spin any event in any way to benefit any party you like?

One telling fact gives it away, I think. If Eskov wanted to demonstrate a realist position, then he could have written the book as if Sauron were a good guy being slandered by the victors. But he doesn't. He writes as if good and evil are nothing but interpretations that a historian imposes upon the record in order to elevate one side over another. This is elementary postmodern historiography: to Eskov, it seems, the opposite of Tolkien's position is not "Sauron's history was misrepresented and he was actually quite decent" but rather "history is fiction and good is relative."

And that is the subtle (and probably unintentional) sleight-of-hand that rankles me. Eskov's project was to characterize LotR as being biased by writing a parallel account in the same world. He must write The Last Ringbearer within Tolkien's fictional world for any comparison with LotR to be valid. Yet the unavoidable issue is that The Last Ringbearer does not take place in Tolkien's world. It takes place in a world where Sauron and elves and magic exist but morality does not, and that is Eskov's world, not Tolkien's world. In such a world, an account like LotR loses by definition. Eskov's project only appears to succeed because he has imported a premise that makes it impossible for him to fail, i.e., it is circular.

That doesn't mean The Last Ringbearer isn't good literature. It's a fine story in its own right, and I am impressed with Eskov's cleverness. But if he set out to write the same story from a different viewpoint, the book does not qualify. It simply isn't the same story if it does not take place in the same world. The comparison cannot be made, and therefore lessons about real-world historiography cannot be drawn.

Well, I take that back. There is a meta-lesson about real-world historiography: don't import premises that make your argument circular. Historians who believe that morality is relative automatically dismiss any moral claim as being non-historical. Historians who believe morality is objective do the opposite. Those are not historical judgments, they are philosophical judgments disguised as history. That doesn't mean that each view of history is equally correct; it means that one of those views on morality is mistaken and you ought to sort that out before you can accurately do history.

Comment: Re:I mourn the alpha chip (Score 1) 172 172

by sasami (#35143024) Attached to: Computer Industry Mourns DEC Founder Ken Olsen

HP transferred the Alpha technology to Intel in exchange for some deals on chips and marketing. That's the last anyone heard of the Alpha.

Though, like many other DEC innovations, we continue to benefit from Alpha today. The next-generation Alpha EV8 was the first chip to implement SMT (hyperthreading). There was an internal legend as to how that came about: rumor was that the chip folks said to the compiler folks, "Hey, we just built an 8-issue processor," to which they responded, "Are you kidding? We can't optimize for that." So they thought for a while and decided to just let the CPU run four threads at once.

Such a pity. The chip was nearly finished when Compaq sold the whole thing to Intel, which promptly canceled it.

Meanwhile the Itanium, dubbed the iTanic, sank.

It was sunk out of the gate. HP grudgingly shipped various revisions of the Alpha EV7 for several years... and if you believe the tech tabloids, Alpha was so much faster than Itanic that HP declared that "not one Alpha benchmark will be released until the Itanium platform(s) is/are faster".


Assange Secret Swedish Police Report Leaked 840 840

Posted by CmdrTaco
from the nothing-is-sacred dept.
letsurock writes "The 68-page confidential report prepared by Swedish police got leaked which tells the police version on the alleged sexual misconduct by the Julian assange. The Swedish report traces events over a four-day period in August this year when 39-year-old Assange had what he has described as consensual sexual relationships with two Swedish women."

Comment: Re:Wait... (Score 1) 911 911

by sasami (#33277010) Attached to: Convicted NY Drunk Drivers Need Ignition Interlocks

a shocking tendency in America recently to give up any liberty asked for in return for the slightest sense of security

You're assuming this is a question of liberty.

Operating your own vehicle on your own property is a question of liberty. Operating your vehicle on public roads is a privilege.

Comment: Re:Religion (Score 1) 892 892

by sasami (#32387356) Attached to: The "Scientific Impotence" Excuse

You seem to have misread much of my post. I have not said most of what you think I have said.

Science is not identical to logical positivism

Indeed, that was my point. Positivism is not a scientific position, but it is held by many who think that it is. It is still not clear to me whether you fall into that category or not.

but it does have axioms. Who said it does not? You can reject these axioms and blab all day to your philosophy class about the matrix. Meanwhile, scientists send people to the moon.

I am surprised. You seem to think that I reject the axioms of science, and reject that the universe is real. Not at all! Exactly the opposite, actually, and I apologize if this wasn't sufficiently clear.

I did state that both the axioms of science and the existence of a real universe are nonempirical claims. But my point was that these are knowably true without being empirical. Therefore:

If you ask me to prove an axiom I will laugh at you. If you ask me to reason without axioms I will laugh at you. What are we left with? A choice between the axioms of scientific reasoning and insanity.

Yes, we are agreed that one cannot prove axioms. Yes, we are agreed that we cannot reason without axioms.

But your conclusion does not follow. It is a false dilemma presented by positivism. On what basis do you adjudicate that no other axioms are justified except the axioms of science? Such a belief would be an axiom, and not a scientific one. In the same vein:

And what of questions that can't be defined in a scientifically meaningful way? We can only conjecture as to the answers. We cannot gain confidence in the accuracy of the answers.

Your conclusion only follows if you also demand that "meaningful" be limited to "scientifically meaningful," which again is good ol' positivism.

And again, the canonical counterexample is the existence of the universe, a question that cannot be scientifically investigated. But I think the universe is real, and I reject the idea that we can only "conjecture" about that. If I understand you correctly, I think you reject that idea also. Therefore, there are at least some statements that are simultaneously: (a) meaningful, (b) true, and (c) not scientific.

But please, don't let me interrupt the blabbing.

Keep in mind that ridicule is not an argument. HTH!

As for your claim that you know the one and only "christian" definition of "faith," you are simply lying.

If by "lying" you mean that I've made a factual error, you're welcome to claim that. If by "lying" you mean that I know better and have written a deliberate falsehood, I'd challenge you to present empirical evidence of such. =)

That said, you may have a point if by "Christian" (including the scare quotes) you mean the range of things that are taught in churches. So let me clarify by analogy: I trust that you do not consider "science" to be the range of things that are taught in science classes. Throughout grade school I knew more science than most of my teachers (I imagine you did also), and they were decidedly not receptive to being corrected. But that hardly prevented me from thinking that my own conclusions were correct.

So when I say that "Christianity teaches X," I mean that I've made an objective determination of what the primary source documents (the biblical texts) are stating, without regard to whatever anyone might teach. Of course I could be wrong, and anyone is welcome to examine my reasoning.

Now, perhaps you think that the interpretation of a text (especially a religious text) is necessarily subjective; I don't agree. Under most circumstances, the "one and only" correct interpretation of a text is whatever the author meant, and therefore we can often reasonably conclude that "Christianity teaches X" or "Dawkins teaches Y." And if you think I have made a mistake in interpretation, you'll have to cite the text and not things you've heard people claim about the text.

In this instance, the definition and usage of the word pistis really isn't controversial. It is the word used in the text, and its meaning is accepted Greek scholarship: to be persuaded of a truth, empirical or otherwise. For the purposes of this discussion, I rephrased it as: to be persuaded of one rational axiom over another rational axiom. Observe that this understanding of faith excludes "believing irrational things" and it also excludes "believing things without good reason". So I find it more than reasonable to state that any Christian who teaches those things has simply failed to do their homework.

But putting all that aside, you haven't yet addressed one central claim of my post: based on the definition I gave, faith is rational. And not only rational, but unavoidable and unproblematic. And especially unproblematic when one relinquishes the positivistic fallacy that nonempirical evidence (such as moral evidence, philosophical evidence, or spiritual evidence) aren't legitimate.

Instead, you are trying to argue that the definition I gave is not "Christian." Perhaps it is because of your unpleasant experience with particular Christians and churches that you so wish to accuse Christianity of being anti-science. But you have yet to argue that point directly.

Result: churches undermine scientific reasoning in the public mind.

Many probably do. No argument there. But so do many other things. They all need to stop. This isn't where we disagree, hm?

Indeed, the above explanation of faith is stridently pro-reason and pro-science. As Whitehead famously observed, "science... is an unconscious derivative from medieval theology."

Comment: Re:Religion (Score 1) 892 892

by sasami (#32385752) Attached to: The "Scientific Impotence" Excuse

Also amusing is your claim that the popular definition of "faith" is "certainly" not the definition used in Christianity, though you can't be bothered to mention the "real" definition.

"Can't be bothered" seems like quite a presumption. Perhaps I was waiting for your responses first? Perhaps because they might be relevant? Perhaps as follows?

Asking for evidence that evidence exists is a silly exercise in mental masturbation. Thanks for the laugh.

It is laughable. My rhetorical question was meant to be obviously absurd (your significant misquote notwithstanding). But the absurdity lies not in the question but in the position.

The notion that "only empirical truths count as truth" enjoyed remarkable popularity for a remarkably short while in the early 20th century. Formally known as logical positivism, adherents advocated that "a statement must be empirically verifiable, at least in principle, to be objective" (that is, to be either true or false). This view demotes all nonempirical statements, such as "humans deserve equality" to mere subjective utterances like "bananas are yummy."

So, my other, non-rhetorical question still stands: is this an accurate understanding of your position, or did I misunderstand you?

I hope it is not your position because it is absurd, as demonstrated by my absurd question. Positivism collapsed immediately upon the realization that positivism is not empirically verifiable. Positivism sets up a standard for truth that positivism itself cannot meet, and is therefore self-defeating. It is not materially different from saying "only ten-word sentences count as truth."

But even if one ignores the logical impossibility of positivism (a self-defeating statement is the opposite of a tautology, after all), it turns out to be utterly unworkable in practice as well. It turns out, upon simple reflection, that everyone in fact believes a great number of nonempirical claims.

Here's a simple example: "The universe exists." Does that sound silly? Let me rephrase: "The universe, rather than The Matrix, exists." Now here we have a claim that is, by definition, impossible to empirically verify. But that does not disqualify it from being true, and one is rarely considered irrational or unscientific for believing in a real universe.

Numerous examples abound, including the laws of logic, moral standards, human rights, and -- of course -- the principles of science itself. These are all nonempirical truths that we hold a priori, and we all know what those are called: axioms.

So, with those preliminaries accomplished, I can answer your objection:

          Faith is the choice between rationally plausible axioms.

This is a succinct summary of the Greek word pistis, which is translated as faith in English versions of the Bible. The Greek word is as specific in its meaning as the English word is vague, and thus I am incessantly met with objections that impute onto Christianity one of the seventeen other definitions of faith that have nothing to do with pistis. To be fair, this vagueness has confused a good fraction of all English-speaking Christians (judging from my own students) and I conjecture that this problem is less prevalent among speakers of other languages.

There is absolutely nothing irrational or anti-scientific about this view of faith. Indeed, our notion of a "rational," "intelligent," "educated" person is of one who accepts -- as nonempirical truths -- the axioms of Reason, the axiom that the universe exists, but not the axiom that God exists. This is an arbitrary cultural distinction, and has nothing to do with being rational, intelligent, or educated.

Your post is amusing all around. Doesn't add to the discussion, though.

Of course it didn't. It was an attempt to get clarification, so that the discussion can benefit.

Comment: Re:Religion (Score 1) 892 892

by sasami (#32382056) Attached to: The "Scientific Impotence" Excuse

Science seeks truth through the systematic application of logic to empirical evidence.

Yup, this is true. But do you hold that only empirical truth counts as truth? If so, can you explain how that that position is an empirical truth?

Faith accepts ideas as truth despite lack of empirical evidence, and in spite of contradictory empirical evidence.

Nope, this is not true. Your definition of "faith," though popular, is not taught by most religions, and certainly not Christianity.

But more to the point of TFA, do you hold that only empirical evidence counts as evidence? If so, can you provide empirical evidence for that position?

Religion promotes faith.

Yup, could be true. But only if the terms are defined correctly. That's a little like saying "Stuff is nice."

Comment: Re:Religion (Score 1) 892 892

by sasami (#32381462) Attached to: The "Scientific Impotence" Excuse

Science is a tool, a methodology. It has no ideology, any more than a hammer or a matchstick has an ideology. That's not to say that proponents or practitioners can't have ideologies,

I'm in complete agreement with this...

but part of the design of science is to eliminate the biases by forcing methodological strictures on research. Science is all about the evidence, ideologies are all, so far as I can tell, about ego stroking.

...but here, you are becoming ideological. The notion that ideology can be eliminated is an ideology. To believe otherwise is merely to mistake some unstated ideology as being part of scientific methodology, and that is what leads some people to incorrectly accuse science itself of being an ideology.

For example, one common ideology holds that non-empirical truths (such as moral standards) do not exist; they are subjective and/or fictional. That is not a scientific conclusion; it is a philosophical assumption. And note carefully that it's impossible to be neutral on this question -- non-empirical truths either exist or they don't.

I find it clearer to use the term "axiom" rather than "ideology." A given practitioner's axioms are an input to the scientific methodology, and this is unavoidable. Yes, this means ideology is inescapable in science, and yes, this occasionally changes the resulting conclusions. But unless one has a well-grounded argument against some axiom, then this is fair game.

Now, this ain't postmodernism, which advocates that all ideologies are valid. No, axioms are objectively true or false, and false axioms will get you false conclusions. But one does not prove an axiom; indeed, some (like AC) are provably unprovable, at least in certain interesting contexts. As far as we know, we humans simply have to admit that all thinking, including scientific thinking, begins with a set of unprovable truths -- and that there will be some legitimate disagreements about what those are.

Comment: Re:I dont use... (Score 1) 896 896

by sasami (#31532120) Attached to: What Free Antivirus Do You Install On Windows?

(Yes, I know it's still technically possible to get a virus. But the chances are extremely slim, given the way I use my computer.)

The chances are extremely slim if you only consider the infection vectors that you know about. I ran my system without AV very successfully for a good while, but over time new vectors cropped up that I was unprotected against. I thought to myself, "This has worked well for a long time," but stupidly equated that with, "This will continue to work well." In fact, the correct conclusion should have been, "It probably can't last much longer."

Security researcher Rafal Los tells this story, which appeared on Slashdot not long ago. Since you won't visit unknown sites, I'll excerpt the key points:

"They volunteered a URL and I started by opening up the page... I tried a few permutations of the common SQL Injection attack [and found that] I wasn't the first to hack at it... someone had not only pillaged their database and broken it - but had also injected it to distribute malware. Malware you say? Yessir... analysis revealed it was a dropper script for the Zeus-bot. So... in 45 minutes the room had gone from non-believers to realizing they not only had a massive SQL Injection problem - but had also been rooted and were now distributing the Zeus bot from one of their main websites."

The author includes some slightly-anonymized screenshots that indicate this is no "seedy" website but the professionally-developed SQL-backed main page of a large restaurant chain. I see no reason to think that Ars or xkcd would be any less vulnerable.

Avoiding the unsafe is easy if the safe stays safe, but it doesn't. Fifteen years ago, users would consult me in a panic upon receiving prank warnings of destructive email viruses. I assured them that email viruses are impossible, because email is not executable. And this was, for a time, true.


NASA Designs All-Electric Personal Flight Vehicle 276 276

Posted by samzenpus
from the touch-the-sky dept.
MikeChino writes "NASA is currently working on a personal aircraft that will put jet packs to shame. The Puffin is an all-electric one-man airplane that could be the start of some new and amazing air travel technology. With two prop electric engines, lithium phosphate batteries and a top speed of almost 300 mph, the vertical take off and landing vehicle was originally designed for covert military insertions because it has a lower heat signature than combustion engines. The Puffin would also be super quiet – 10 times quieter than current low-noise helicopters, and since the engine is electric it has no flight ceiling and can fly up to 9,150 meters high, uninhibited by thin air."

Chemist who falls in acid will be tripping for weeks.