Saturday, August 29, 2015

Drying

We were silly enough to get a low-noise dishwasher, and found the hard way that grinding up stuff makes noise: no noise means little grinding means the thing clogged more often. When it broke we went back to manual operations. Since we had to pre-clean the dishes for the machine anyway, it isn't a hardship to do without--though certain family members are more thorough than others.

My habit is to wash plates and silverware and some of the glasses as the first load. Sometimes someone comes to dry the dishes so I can continue. It seems a waste of time and effort: just wait 5 minutes and the dishes will be dry by themselves. (Also it makes my "first load" a much larger affair. But I digress.) Later loads require the towel; they don't dry quickly.

My impressions are that ceramics tend to dry very quickly, plastics very slowly, and metal somewhere in between. I wonder how much this has to do with wetting and how much with thermal conductivity and how much with thermal mass. And how much with the effects of thin films of oil, that is so hard to get off plastic, spreading to cover water droplets and block evaporation.

Wetting and evaporation may not be as trivially linked as you might guess; apparently there's a body of literature on the subject. One little detail, obvious in retrospect, is that a drop of water forms a shape governed by its surface tension and how strongly it wets the surface. OK. Now some evaporation happens, and the shape of the droplet is different--if water escapes uniformly according to air speed (higher farther away from the surface) the drop flattens out, and no longer has the ideal shape for balancing the forces involved. What happens next?

Thermal conductivity matters too. If the surface is still hot from the hot water, evaporation will cool it down. But if more heat is quickly conducted from the inside, the surface stays relatively hot and the water keeps evaporating. So you'd think iron would dry faster than ceramic. But water's heat capacity is much larger than iron's, and a little evaporating water can cool quite a bit of thin iron. (Some plastics have heat capacities larger than ceramics.)

Complicated.

Friday, August 28, 2015

MacDonald

C.S. Lewis credited George MacDonald with "baptizing" his imagination; that when he read Phantastes it aroused a special sense of awe and mystery like nothing before; a sense that stayed with him for the rest of his life.

In that mysterious land the hero is a bumbling failure: "Alas, how easily things go wrong! A sigh too much, or a kiss too long, And there follows a mist and a weeping rain, And life is never the same again." But MacDonald was a Universalist, and wrote of hope beyond any disaster.

I liked Lilith better when I first read the books; it seemed to have a stronger narrative, and I liked the characters better. But youth doesn't always understand Fairyland, and I think it is time to read Phantastes again.

Sometimes you re-read a book because you need a little familiar amusement. Sometimes you re-read it because you need to hear the voice again; because you need to be reminded of something important. Last month I went back to A Canticle for Leibowitz.


This chapter of Lilith reminds me of the ending of The Last Battle.

Thursday, August 27, 2015

Illumined faces


I boarded the bus early Wednesday morning (nobody showed up for the 6:00 Bible study) and sat across from a young lady whose rapt face was illuminated in the dim morning in a way I finally remembered having seen before. Except that it wasn't a child she held.

Livelier baseball

My Better Half is the baseball fan.

I think the game would be much livelier and more interesting if so many innings weren't pitchers' duels.

Suppose for the first 6 innings the opposing team got to pick which player would be the pitcher. (Nobody could be required to pitch more than 2 innings if they and their coach disagreed.)

Each position player would have to be more of a utility player, since he'd never know from inning to inning where he'd be. Except for the late inning closers, of course--that's still enough of a tradition that we should probably keep it.

This opens more opportunities for strategy: who do you pick as pitcher, and how do you defend against losing (e.g.) your best catcher to the pitcher role for an inning?

And there'd almost certainly be more hits, more infield and outfield play--a livelier game. What's not to like?

She doesn't like the idea.

Saturday, August 22, 2015

Sorrows

Pack up your sorrows by Richard Farina and Pauline Baez Marden was covered by some big names--the link is Johnny Cash. A duo at the Corn Fest played the song this evening--the first time I'd heard it since the early 70's.

Strangely enough, the last time I'd heard it was in church. "But if somehow you could pack up your sorrows And give them all to me You would lose them, I know how to use them, give them all to me."

It seems to fit about as well in church, maybe a tad better. An artist telling someone that he know how to use sorrows (presumably making songs of them) seems a bit callous, and the unlikely "you would lose them" is conditional on that "if somehow."

Jesus, on the other hand, can use sorrows. I suggested a time or two or three that suffering can be a means of union with God. For some of us it seems to be the main means here on Earth.

Once again though, you don't "lose" those sorrows. That seemed to be the implication of the song's use in that youth group eons ago, but I think I'm safe in saying that it just isn't true. There can be compensating joys, and sharing sorrows can sometimes lessen the pain. "I know. Grief is great. Only you and I in this land know that yet. Let us be good to one another."

Friday, August 21, 2015

Thunderstorms

We still don't know quite a few things about thunderstorms, such as why one sometimes gets the red sprites shown in the linked picture. You can fly planes in and around them and the instruments tell us quite a bit, but they're so big our probes only catch a little of it.

I wonder if it is possible and useful to instrument a valley with chirping polarized radio transmitters and have receivers on planes or balloons measuring the Faraday rotation of the polarization axis. It isn't the same as a point measurement, since it integrates the magnetic effect along the whole path length (miles), but as the storm moves through the valley you'd get different sections through the storm, and maybe be able to tell if there were regions of exceptionally strong magnetic field.

If the Sun can have an effect on lightning rates, it might be nice to test models of how it works.

Gossip

The Ashley Madison crew are extraordinarily revolting specimens of fallen humanity, and their (mostly male? surprise, surprise ...) customers were remarkably trusting fools (can you say "Please blackmail me"?), but the team that published the records is just as wicked--though probably more self-righteous about it. FWIW, how can you be sure that addresses weren't interpolated into the collections before they were tar'ed up and checksummed?

Gossip doesn't have to be false.

I know, the truth shall make you free--but that's not the purpose of any of the parties here.

Thursday, August 20, 2015

Asymmetry

"Big data" analysis, facial recognition (they'd probably do better to use two cameras to get stereo and avoid the problems reconstructing features in the presence of shadows and discolorations), cameras on the street, speed cameras, cell-phone tracking--like living in a small town; everybody knows everything you do. Except that you know nothing about those "everybodys."

Monday, August 17, 2015

Ads against the enemy

Some years ago I posted an essay on the war we’re engaged in and on approaches to countering enemy propaganda. I still judge the war to be a religious war, and some of the traditional VOA paradigms are useless at best, and the ubiquitous Western media tends to injure our cause more than help us.

I didn’t address the capabilities of our amazingly effective advertising propaganda industry. Surely we can, with all the psychological research and experience and tools at our disposal, out-do Daesh propaganda.

Our ad experts can’t just translate their ads into Arabic, though. We’d need people thoroughly versed in Arabic literature and poetry and history in its various flavors, who understand how people in one tribe view others just as a good ad man knows how to pitch a beer ad in Wisconsin by lightly mocking “metrosexuals.”

This isn’t the acquisition of a year’s study.

Should the goal be to make Daesh look stupid, or nasty, or hypocritical—or some combination? Given their actions any or all of these should be possible for a sophisticated team. The other side of the question is “What do you want to hold up as the proper ideal?” I don’t know that we have a lot of choice in that: you have to work with the urges you find in the population, not those you wish they had. I still think the “House of Fruit” approach would be useful. But the ads will probably tend to encourage more, not less, tribal behavior to counter the appeal of a new caliphate. And they won’t tend to increase sales of US products—might be fewer. This won’t endear them to the usual suspects in State. Nor will it tend to encourage them to become Christian—and I for one want them to.

Of course, the effort could not have any official connections whatever—it would have to appear entirely indigenous. A whiff of Western support would be the kiss of death.

Suppose there were some adults in the room, and this was actually attempted as a news source. What would it look like? To maintain its credibility it would oppose the US and Israel. It would try to maintain a reputation for accuracy. If it were regional, it would try to have local outlets tailored for different markets. Funding would be transparently local. And the overall thrust would be against centralization under would-be caliphs. Does Al Jazeera do this (in Arabic, not English)? No, I don’t believe it to be American-funded—DC can’t keep secrets.

Black propaganda anti-Daesh videos are hard to imagine—the group is so far out there that only accusations of hypocrisy would seem to work—and those would not discourage other would-be caliphs. I’d think that nominal amateur news videos could be inserted into the stream with good plausibility. Do we see anything like this? (I don’t, obviously...) There are videos out there; are they effective with the target audiences?

Thursday, August 13, 2015

Wisdom is as wisdom does

Years ago my parents bought the Great Books series and the study guides for it. I ignored the guides and read those books that looked interesting (not even half of them; and what a terrible font!). I have them now—the Shakespeare volumes in tatters thanks to Youngest Daughter. (I think almost all of them can now be had for free via Project Gutenberg—a university education in your kindle for just the price of your time.)

I finally got around to reading Volume 1: The Great Conversation, The Substance of a Liberal Education by Robert M Hutchins. His thesis is that the Western liberal education consists of understanding the ongoing debate between great writers, that this was originally intended for those with leisure who would govern, and that in our wealthy and nominally self-governing society this is an appropriate education for citizens; especially for continuing education for adults.

A man must use his mind; he must feel that he is doing something that will develop his highest powers and contribute to the development of his fellow men, or he will cease to be a man.

and

Here we encounter the melancholy fact that most of the important things that human beings ought to understand cannot be comprehended in youth. … I have never known a child of any age who had much that was useful to say about the organization of human society or the ends of human life.

and

In fact my observation leads me to the horrid suspicion that these books are easier for people who have had no formal education than they are for those who have acquired that combination of misinformation, unphilosophy, and slipshod habits that is the usual result of the most elaborate and expensive institutional education in America.

(That was in 1952. I hate to think of what he’d make of the offerings today.) The last line of the book is:

The aim of education is wisdom, and each must have the chance to become as wise as he can.

That last line is key. Perhaps I read too carelessly, but I recall very little mention of wisdom in the book before that last line.

That makes a rather odd contrast with Proverbs, which the Wednesday Bible study is going through right now. It hammers away at the need for wisdom. Hebrew parallelism or semi-parallelism mates wisdom and understanding in many verses; they aren’t quite the same, and neither is the same as knowledge.

A for-example about understanding vs knowledge: When I arrived at U of Illinois I showed up at the department and found to my surprise that I could have a free-shot at the qualifier exam; typically you got two chances and if you failed both you were out on your tail. The exam was the next day, so I had virtually no study time. I didn’t have anything to lose. If I passed I was in and if I didn’t it wouldn’t count against me, so I showed up with a weary head full of leases and U-Haul. One of the oral questions was to write Gauss’ law on the board. My memory took the opportunity to step out for a walk, but I remembered the basic symmetry involved and re-derived it. The examiners looked at each other and went on with other questions. I was a little short on ready knowledge, but I had enough understanding of the subject to make up for it. Almost. (I didn’t pass that time.) On the other hand, in statistical mechanics everything seemed quite clear and logical until the quiz and its “The atomic number of copper is 29. Calculate its specific heat.”

But wisdom seems to be something different in kind from understanding; more like an applied understanding of the principles of living. I can understand that lotteries are a bad deal and that steady earning is better for long term financial security than the moral hazards that come with windfalls, but if that understanding doesn’t keep me from impulsively buying tickets it hasn’t translated into wisdom. If I don’t understand statistics but have the humility to take advice from someone who does, and refrain from buying tickets, I’m acting wisely even though I lack the understanding of the reasons.


What’s education supposed to provide, then?

Basic knowledge: reading/writing, some math, some facts about the physical world, some facts about human society, some history, some skills. Some analysis as far as the student’s abilities take them: how things are connected in a field. Some what-ifs and whys: what the various possibilities were and what were their upsides and downsides in designing a political system. Good literature that provides a common language and a sampling of the different ways of thinking about things. (The “dead white males” have only that in common—I can’t imagine Bentham and Plato seeing eye to eye on pretty much anything.) Beautiful things and how to make them—art, music, literature.

Opportunities to exercise wisdom and virtue: We can’t compel courage or justice, but can we try to encourage them? I’m pretty sure these don’t fit very well into a K-12 curriculum sequence; real virtues need real circumstances to exercise them, not just workbook exercises. The copybook headings can remind the children of what we expect, but that’s about all. Schools try to teach approved attitudes, but these bear little resemblance to the cardinal virtues.

Our kids were all over the map as far as who was ready to understand what at which age, and for how long at a shot they could ingest information in some field.

I guess that most kids fit OK into a one-size-fits most curriculum that includes lots of review of earlier year’s work (a la Saxon math?). There’s not a lot of discussion of the great ideas, but perhaps, as Hutchins suggests, that’s not something you can expect out of most youngsters. I still think some intro to philosophy would be beneficial, but maybe only for the oldest.

I’m certain the K-12 sequence isn’t efficient for most of our children. In Wisconsin even home schoolers have to respect it, though—you must be able to document at least 875 hours of instruction. But if you can catch the child at the opportune moment they can learn a lot in a short time.


What’s missing from the formal curriculum?

  • Work—starting with chores and growing to real-world work for outsiders. That gives training in service, self-discipline, and probably fortitude and temperance as well.
  • Learning how to interact with people—most kids pick that up automatically, but not all. Not all.
  • Practicing living your place in the world—that sounds kind of vague, but most of us have some notion of where we will eventually wind up in the grand scheme of the world, even if we have great ambitions to the contrary. Are we ready to live the non-rock-star life we’ll probably have? Temperance, prudence, justice… humility

I’m just creeping around the big questions here. For adults I think Hutchins is more or less right about a liberal education—grab some of the books and read for yourself. If possible, find somebody with whom to argue about them, otherwise argue with the authors. (You’ll probably win most of the time when the authors are dead.)

For kids—everybody wants credentials that prove you’re not a dunce and have mastered the basics. OK, we can do that with tests. But for the real education (“I have never let my schooling interfere with my education.” Twain), who does what, and when?

Thursday, August 06, 2015

Kids

Is it fair to say that kids drive you crazy, but they're good for your mental health?

Sunday, August 02, 2015

Watering the plants

The back porch has a number of plants in various types of pots, and these tend to need more water than plants in the ground--the dirt gets hotter. And when we don't get enough rain we run the hose over the gardens. (The lawn can fend for itself.)

The soil is an extremely complicated community of fungi and bacteria and tiny animals, and it only just occurred to me tonight that the tap water has chloramide (and probably some fluorine compound as well). Quick googling says yes, this can sometimes cause problems (and sometimes it doesn't make any difference) and getting the chloramide out isn't altogether trivial. People aren't terribly clear about the detailed causes of the problems when they do happen, but nobody understands soil ecology very well so that's not surprising.

I tried rotting out a tree stump using the "drill a bunch of 1" holes, with side vent holes and pour in potassium nitrate and water" method. (Other sources suggested setting the stump on fire after that mix had a chance to percolate, but I'm not interested in melting the underground cables that lace our little berm.) Yes, we finally got some mushrooms growing, but a year late, and the stump still has most of its structural integrity. Maybe the tap water I poured in killed the fungi, and the potassium nitrate didn't have much to fertilize?

Maybe I need to reroute the downspouts into rain barrels. Or call UW Extension. That sounds easier.

Followup on the library sign

Two years ago I worried about how the local library sign would be used, including the probability that the homeless would nestle behind the giant letters. I neglected to show how that was forestalled. There's a vertical bar in between the wall and the back of the letters. There's not enough free space to nestle.