A Computer Hardware Mini-HowTo

How to install a 2.5-inch (laptop size) hard drive in a 3.5-inch (desktop size) drive bay:

  1. Search locally or on the internet for an appropriate mounting bracket designed for mounting a 2.5-inch disk in a 3.5-inch bay. Buy it.
  2. Shut down and unplug the computer into which the hard disk will be installed. Open up the computer’s case.
  3. Discover that the mounting bracket you bought is physically incompatible with the drive bay and/or the hard disk.
  4. Scrounge up some string, cardboard, and rubber bands.
  5. ???
  6. Close the case, plug the power cable back in, boot up, and write a blog post describing your daring exploits.

Getting It On (And On, And On…)

What. The. Fuck.

Police in Orlando, Florida claim “a typical prostitute that’s HIV-positive could potentially infect more than 18,000 people a year.”

Taking into account HIV transmission probabilities, Classically Liberal estimates that SuperProsti would have to serve at least “9 million customers [per year]. Disney World only manages 27 million.”

Am I A Racist?

Two excellent posts from Megan McArdle show why it is very difficult for any of us to answer that question with any certainty. (Well, it’s an easy question to answer for people who are openly and proudly racist. For the rest of us who’d like to think the answer is no, it’s a fine little epistemic quandary.)

Old Hardware, New Hardware

My recent lack of blog activity owes partly to school, and partly to the fact the my laptop finally died (it had been on its last legs for a while). I replaced it with a desktop box from Dell; desktops are a lot cheaper, especially in light of the comparatively short life expectancy of laptops. I considered buying parts and building a desktop myself, but doing so is no cheaper and a lot more hassle.

The box actually came with Ubuntu Linux installed, but to get things set up to my satisfaction I had to do a fresh install anyway. I’m presently running Kubuntu (i.e. Ubuntu with KDE, not Gnome). I’ve got the recently released version 7.10, “Gutsy Gibbon”. Works beautifully. In particular, Kubuntu supports all my hardware flawlessly with only a very tiny amount of work on my part. Linux has come a long way since I first used it.

My New Road Bike

trek-madone.jpg I bought a Trek Madone 5.0 to replace my stolen road bike. It’s a 2007 Madone, not one of Trek’s newest-generation 2008 Madones; Trek’s fancy new design is the reason that this bike was marked down to a price I could afford. Regardless of the new 2008 Madone, this bike is still a wonderful machine. The frame is all carbon fiber. It rides out the bumps with aplomb and still transmits power very efficiently. My Madone isn’t the lightest bike on the market, but it feels like a feather compared to the steel-framed Bianchi Eros I had previously. The handling is stable and effortlessly natural — the bike responds exactly as I expect it to. Altogether, the Madone rides like a dream.

Shopping for bicycles was fun, although considering how many times I drove back and forth across Albuquerque in the process I’m not sure my purchase did much for the environment. I rode a lot of bikes. Most of them were perfectly good machines, but all of them are different, and ergonomics and subjective preference play a large role in one’s opinions of bikes. The only truly bad bike I rode was a Kestrel Talon, which had remarkably unstable handling. Then again, some people ride them and like them, so maybe it’s overreaching to claim that the Talon is an objectively bad bike (though it’s hard to imagine how anyone could like that thing).

My favorite bikes, aside from the Madone, were a 2007 Jamis Eclispe and a 2006 Giant TCR1. The former is a mixed steel and carbon fiber frame; it’s an uncommon combination, but the bike rides wonderfully smoothly, and it has character. Though the Eclipse has undeniable appeal, the Trek and the Giant are lighter and stiffer and ride almost as smoothly. giant_tcrcomposite1.jpg The Giant TCR1 is a full-carbon bike which felt quite similar to the Madone; I’d be very happy on either bike. After hearing several anti-China quips from salespeople trying to sell me bikes made in America and Europe, I was rather tempted to buy the Giant to spite them — I think that sort of economic nationalism is perfectly odious. But ultimately I followed the guidance of a less spiteful cosmopolitan spirit and simply bought the bike I liked best for its own qualities. The Trek Madone was somewhat cheaper than the Giant, and I think it cuts a more elegant image.

I’m on the road again. Woohoo!

Technophobia Keeps People Off Bicycles???

I read the following quote in a Wired article:

sales associate Babs Brockaway says she’s seen the number of customers leaving with shiny new fixed-gear (”fixie”) and single-speed bikes skyrocket. …The simplicity appeals to neophyte riders overwhelmed by too much technology. “It’s simple: You just pedal,” she says. “This is shocking, but there are people who buy bikes with gears, who don’t shift gears.”

…and I dismissed it as an anecdote.

Then I found out that Shimano and Trek have both confirmed this in recent market research.

Both sets of research determined that people who hadn’t ridden for some time were intimidated by multiple gears and complex shifting systems and didn’t feel comfortable using cable hand-braking systems. This untapped market, the research showed, longed for a simple bike that reminded them of childhood. “Expecting someone to learn how to shift is a pretty tall order for someone who hasn’t ridden since they were a kid and is now 40 years old,” Bryant says.

It’s one thing to not know how to assemble a bike from scratch, or write computer programs, or fly an airplane. But shifters? Hand brakes?!? Like Babs, I too am shocked.
Image: the Lime bicycle, by Trek
Although I’m rather horrified by the commonality of such extreme technophobia, I applaud the industry’s efforts (such as the Trek Lime) to get “mainstream consumers” to ride bikes. These people should not be driving cars.

Pure Math, Applied Math, and A Priori Proofs

Some people think that scientists doing theoretical work can use mathematics to prove things about the real world a priori of any empirical investigation. This is wrong. Allow me to explain.

It is true that the results of pure mathematics do follow from whatever axioms one starts with a priori of any empirical observations. Indeed, empirical observations are quite irrelevant to pure math (except in an inspirational role). However, mathematics by itself cannot tell us anything about the physical world.

A concrete example will help illuminate the relationship between math and the physical sciences. Let’s consider the theory of General Relativity. GR is a mathematical model, and there are a couple of different ways to look at a mathematical model.

A pure mathematician might just be interested in the abstract “mathematical formalism” of GR. This pure mathematician could study the Einstein field equations, et cetera, irrespective of their physical significance. Indeed, an alien mathematician in an alternate universe with completely different physics could study the same mathematical formalism and derive the same results, even though the theory and results would have no physical significance in that alternate universe.

However, there’s more to a mathematical model than just an abstract formalism. A mathematical model additionally makes the empirical claim that the behavior of the real world is analogous, in a specified manner, to the behavior of its abstract formalism. This linkage between the formalism and the real world is sometimes called “the interpretation” (especially in cases where there is controversy about just how to link things up, such as quantum mechanics).

To return to the example of GR, you can derive from its mathematical formalism (in a completely abstract, a priori manner) the existence of gravitational waves. However, this most certainly does not prove that gravitational waves exist in the real world. It might turn out that there are no gravitational waves and the real world doesn’t behave in the way the model says it should. It might turn out that the model is wrong.

In light of the empirical fact that the predictions of GR have thus far agreed with experimental tests, physicists believe with fairly high certainty that GR does accurately model the behavior of the real world. We have not yet experimentally observed gravitational waves, but you’d be hard-pressed to find a physicist willing to bet money against their existence. No one, however, thinks that we’ve proved, a priori, that gravitational waves exist. If scientists did think their existence had been proved a priori, we wouldn’t bother going to the great trouble and expense of attempting to find empirical evidence for them.

In some cases, the correspondence between a mathematical model and the real world is so obvious and uncontroversial that no one bothers to explicitly lay out the formalism’s interpretation or the empirical evidence for its correctness. Consider a basket with 2 apples in it. Now toss in 2 more apples. Examine the basket, and you will find (surprise!) 4 apples. However, you cannot prove a priori that there will be 4 apples in the basket. It is an empirical question, albeit a trivial one, whether baskets of apples (which are physical things) behave in the same manner as the non-negative integers under addition (which is an abstract logical construct).

This distinction might seem hopelessly pedantic at first, but you can easily go astray by ignoring it. For example, many people naively expect photons to behave in the same manner as integers under addition, but they don’t. “Number of photons” is not a conserved quantity in the way that “number of apples” is; photons can be created/destroyed, one photon can be split into two, et cetera. Richard Feynman tells an interesting story about trying, and failing, to explain to his father how photons can do these things. I strongly suspect his father was implicitly assuming that all “particles” — a rather misleading term — must behave like apples and integers under addition. However, once you clearly understand the distinction between abstract math and empirical questions, it becomes clear that there is no a priori reason to believe that photons behave like apples or integers.

Without empirical evidence, math can’t tell us anything about the physical world. Scientists have never, ever proven anything about the real world a priori, and never will.

Links! Get Yer Links!

bio-building.jpg

More On Peter Williams: The Ontological Argument

Here’s an abstract view of how the Ontological game is played.

A philosopher constructs some property, p, and asks you to consider the following statement:
(1a) You can imagine that a thing with property p exists.
Or alternately, if the philosopher wants to use modal logic,
(1b) It is possible that a thing with property p exists.
Now, unless p is blatantly self-contradictory, proposition 1 (in either version) usually appears pretty plausible. Of, course
(2a) You can imagine that a thing with property p does not exist.
and
(2b) It is possible that that a thing with property p does not exist.
also seems pretty plausible.

Now for the trick. A clever philosopher can construct a p such that (1) and (2) can be shown to contradict each other! How should we resolve this awkward situation?

Before going any further, let’s make this slightly less abstract. Specifically, suppose that in addition to the above, p is some manner of “god-like” property; that is, p is constructed so that it is natural to identify the thing exhibiting property p as god.

So, what are we to conclude from this state of affairs?

Some theologians want to claim that this proves that god exists. This is not terribly persuasive in absence of some good reason why we should accept (1) and reject (2), rather than vice-versa.

Williams wants to claim that the ontological argument shows that atheists must absolutely reject the possibility that god exists. This is imprecise. What is shown is that atheists must reject the possibility that a thing with property p exists; invariably, it’s possible for a being to be quite recognizably god-like without strictly exhibiting p. This shouldn’t come as a surprise to anyone, since it’s not the first time someone attributed properties to god which turned out to be paradoxical. For example, omnipotence (or, at least, a naively literal conception of omnipotence) is a thoroughly paradox-ridden concept. But even if omnipotence is paradoxical, and some people say god is omnipotent, this doesn’t imply that god doesn’t exist. A being who is not literally omnipotent could still possess powers deserving of the appellation “god-like”. Likewise, in these ontological arguments, to reject the possibility that a thing with property p could exist isn’t the same thing as concluding a priori that god (in the more general meaning of the word) cannot possibly exist.

Alvin Plantinga wants to claim that the ontological argument, though it doesn’t actually prove that god exists, demonstrates that it is rational to believe that god exists. Basically, he’s says that we have to either accept (1) and reject (2), or vice-versa, and the former option is just as good as the latter.

Actually, no. There are excellent reasons why we should accept (2) and reject (1) whenever we are confronted with this situation. Like Hume and Dawkins, I think that it’s pretty laughable to attempt an a priori proof of the existence of anything. Playing word games and examining your own mind just isn’t going to tell you that much about the world outside of your own skull.

But maybe you don’t share our empiricist leanings. Even so, you should reject (1). The reason is this: if you accept (1), it is ridiculously easy to use ontological arguments to prove the existence of all sorts of silly things. Here’s one example:

  • I can imagine a maximally sexy woman.
  • Youthful women are sexier than old/dead women; mortal women must eventually grow old and die, and thus be less sexy than an immortal, eternally youthful woman.
  • A woman who exists in the real world is sexier than one who only exists in my mind.

Hence, there must exist in the real world an immortal, eternally youthful, maximally sexy woman; let’s call her, oh, Aphrodite. To the best of my knowledge, this ontological proof is original, although I wouldn’t be too surprised to find out that someone else thought of it first. The philosophic literature has no shortage of parody ontological proofs. (Exercise for the reader: use an ontological argument to refute the second law of thermodynamics. Hint one, hint two.) Ontological arguments are pretty much the quintessential example of bullshit sophistry.

It is possible, in principle, that all of the many, many ontological parodies are flawed, and somehow, the only true contradictions between (1) and (2) occur for p’s which are “god-like”. But if any of you are tempted to start a crusade against ontological parodies, please pause for a moment. Pause to ask yourself whether your desire to start skewering ontological parodies stems from an earnest desire to discover the truth, whatever it may be, or from a need to provide the less credulous part of your mind with some justification for believing what you already believe and want to keep believing.

Zombie Apocalypse

zombies.png
I need to buy a crowbar, stock up on canned food and water, put in some practice time at the shooting range, and go running more often and for longer distances. Doing so will up my chances to 79%, supposedly.

My brother Stillman scored quite a bit better than I did. Terre Haute, Indiana (where he is a chemistry major at Rose-Hulman) has fewer people future zombies than does Albuquerque, and he knows far more about explosives than I do.

What are your chances of surviving a zombie apocalypse? (If it turns out that they aren’t good, I suggest picking up a copy of The Zombie Survival Guide by Max Brooks.)