Tuesday, September 20, 2011

Let play pretends

Burning Man: Why would anyone go? - By Seth Stevenson - Slate Magazine

I do find this event hard to fathom, but I think someone in comments comes close:

I love how today's version of "Hippies" are upper-middle-class white people with plenty of money to take some time off from work, pay hundreds of dollars to get to/in an event where they can pretend they're "Counter-Culture" for a weekend.

Appalling stuff

More Cherry Ice from Joe D’Aleo | Open Mind

Read this, and the earlier post it links to at the beginning, to see the appalling examples of dishonest misinformation that get posted at Watts Up With That as part of climate change "skepticism".

Monday, September 19, 2011

A strange case of celebrity

gulfnews : Yemeni enjoys drinking motor oil and radiator water:

Riyadh: A Yemeni resident of Makkah who is employed at a vehicle maintenance workshop has been stunning viewers by drinking engine oil, radiator and battery water.

The Saudi Akaz newspaper said on Thursday that the Yemeni, Mohammad Omar, nicknamed "Bin Omar", drinks two to four cans of all motor oil daily.

He told the newspaper that "I enjoy drinking radiator, battery and brake water, and eat daily 2.5kg of grease used for cars. I have been doing that for quite a long time".

Omar added that he has been doing that as he spends 900 Saudi Rials per month to buy oil, grease and their derivatives as meals. "Praise Allah, my health is good", he said.

Uh huh.

Malaysian solution not the end of the world

Toxic Policy Helps No One | Asylum Seekers

It's interesting to note that in this article in which onshore compulsory detention for processing asylum seekers is strongly criticised, the writer still ends on this note:

That said, it is also prudent for Australia to pursue a regional agreement to handle the huge flow of refugees from strife-torn nations such as Iraq, Pakistan, Afghanistan, Burma and Sri Lanka. No single country can cope with this massive movement of people - not Australia, not Malaysia, Thailand or India.

On paper at least, the deal with Malaysia, which also provides for community-based processing, appears to be a balanced alternative to Nauru and Manus Island, where people would be detained in cultural and geographic isolation while their claims were assessed.


As I have noted before, the local UNHRC was also not appalled at the Malaysian idea, and Coalition supporters who have been acting as if it was the worst idea in the world have been ignoring the psychological suffering of the Nauru system which had originally led those who voted for Rudd to have some sympathy towards relaxing the whole system.

My belief is that voters don't know what they want for the asylum seeker issue. This is reflected in the polls which have actually indicated a majority support on shore processing, yet a large number also think the Coalition does a better job on the issue than Labor. This contradiction makes no sense at all, if you ask me. If the explanation is that people hate asylum seekers arriving by boat, and expect a government to stop that, how do they reconcile that with support for on shore processing which is surely going to do nothing to discourage boats from arriving?

I feel sorry for the Labor government trying to work out how to keep the very confused public happy on this issue.

More complicated that you thought?

We need to talk about HPV vaccination – seriously - opinion - 16 September 2011 - New Scientist

It's a bit surprising to see New Scientist running an opinion piece that questions whether the grounds for universal vaccination of girls with the HPV vaccine are really well enough established.

A possible explanation

Deep oceans can mask global warming for decade-long periods

Here's a good, succinct report on modelling that indicates the deep oceans indeed may be absorbing the "missing heat" that Trenberth wrote about famously in his "Climategate" email.

To track where the heat was going, Meehl and colleagues used a powerful software tool known as the Community Climate System Model, which was developed by scientists at NCAR and the Department of Energy with colleagues at other organizations. Using the model's ability to portray complex interactions between the atmosphere, land, oceans, and sea ice, they performed five simulations of global temperatures.

The simulations, which were based on projections of future greenhouse gas emissions from human activities, indicated that temperatures would rise by several degrees during this century. But each simulation also showed periods in which temperatures would stabilize for about a decade before climbing again. For example, one simulation showed the global average rising by about 2.5 degrees Fahrenheit (1.4 degrees Celsius) between 2000 and 2100, but with two decade-long hiatus periods during the century.

During these hiatus periods, simulations showed that extra energy entered the oceans, with deeper layers absorbing a disproportionate amount of heat due to changes in oceanic circulation. The vast area of ocean below about 1,000 feet (300 meters) warmed by 18% to 19% more during hiatus periods than at other times. In contrast, the shallower global ocean above 1,000 feet warmed by 60% less than during non-hiatus periods in the simulation.

"This study suggests the missing energy has indeed been buried in the ocean," Trenberth says. "The heat has not disappeared, and so it cannot be ignored. It must have consequences."


I wonder if work is being done on measurements to confirm it?

The future of food guesswork

Increasing Focus on Climate Change/Food Crisis:Beware ‘Single Factor’ Explanations, Uncertainties | The Yale Forum on Climate Change & The Media

I just note this article from earlier this year that details a lot of the uncertainty that revolves around the issue of future food production under global warming and increased CO2.

I would suspect that, since the last IPCC report, there would have to be greater concern developing about the future effect of extreme weather events on local and global production.

A bit of a worry...

A first glimpse at model results for the next IPCC assessment | Serendipity

Quite an interesting post here about some modelling runs which show the importance at looking at the long term future (not just up to the end of the century.)

Notes from all over–Spring edition

Because those making $1,000,000 a year are hurting.   How silly are Republicans who chose to call Obama’s proposal that tax be increased for the rich “class warfare”?     Very stupid, in my books; but then again, what do I expect from a party that is being held captive on what it can say about climate change by the Tea Party element?  

Jerry Pournelle has looked at the new NASA heavy lift vehicle proposal and is not impressed.   I don’t trust his skeptic assessment of climate change, but he knows a lot about rocketry and its developmental history, and his criticisms here are worth considering.

*  Americans not only have an un-natural degree of embarrassment over the sight of a used clothesline, they are not big on washing clothes in cold water either.  (But then, nor are Germans, according to the article.)   I would be very surprised if the majority of Australian washing is not done in cold water now.  The report says the Japanese mainly use cold water; why is there resistance to the idea in the US?

*  Good news for the PM?   At least one Labor idea, a mining tax, is quite popular according to a survey.   This is not the first survey to show this.   Doesn’t this mean that the Coalition promise to undo everything Labor implements might not get quite the universal acclaim that they expect it to during an actual election campaign, despite the fact that people are at the moment  in such an irrational  “anything but Gillard” mood  that they couldn’t care less what Tony Abbott is saying?

*  The New Yorker has a somewhat amusing article on sexual revolutions of the past.  I liked the bit about the “celestial bed” (top of page 2) in particular, because I hadn’t heard of it before.   It might have been a bit disturbing for the neighbours, I expect.

*  The possum under the balcony is getting and more used to us.  We feed it fruit most days now: 

Possum

Sunday, September 18, 2011

Fish success

Last year, I posted a Mediterranean baked fish recipe which had been a success. For whatever reason, I haven't ever cooked that again, but last night I tried another Italian type of baked fish recipe by Neil Perry, which was in last weekend's Sydney Morning Herald. It too was a success, so I'll paraphrase it here:

Thinly slice a fennel bulb, a red onion, and a red (or as I used, yellow) capsicum. Skin, seed and dice four tomatoes and chop up a bit. Put in a flat type of casserole and mix most of 60 ml of olive oil. Add 6 anchovies, as many capers as you like (washed), and olives, and mix up with the veges. The recipe called for chilli flakes too, but as the kids were eating it, I left them out. Season liberally with sale and pepper.

Roast in 200 degree oven (uncovered, but you might have to stir around a bit half way through if your oven has hot spots) for one hour.

Put white fish fillets in a single layer (hence the flat casserole pan) into the sauce, put the rest of the olive oil over the fish, and back to the oven for maybe 15 minutes.

The roasted veges make an excellent sauce, and even the kids were happy to eat it (although I didn't serve them the olives.)

Thank you Neil: very nice.

(But then, I love fennel in anything.)

Friday, September 16, 2011

What 2 degrees means

It's a favourite line of some climate change skeptics that, if the world has already warmed up .8 degree over the 20th century, and the effects haven't been so bad, would we even notice an average warming of 2 degrees in future.

The argument is, I would have thought, obviously flawed for many reasons, not the least of which being that what climate scientists are actually saying is "hey, you'd better start working freaking hard even to have half a hope of keeping it to 2 degrees." The stupidest version of the skeptic argument says "well, so what if a previous hot day of 35 degrees becomes one of 36.5 degree?" You can point people to this well know bell curve:



but it doesn't seem to register that what is means hotter seasons, not just individual days.

So, they should read about research like this, indicating that what we currently consider an extreme summer will, in large parts of the world, become extremely common:

Researchers from Stanford University recently set out to learn at what point exceptionally hot summers will to become more commonplace around the world. Climate scientist Noah Diffenbaugh has studied how the warming to date has influenced the weather patterns that lead to unusually hot seasons. Projecting forward over the next few decades, he says the combination of warmer temperatures and changing weather patterns mean that the extremes will be changing quickly.

"According to our projections, large areas of the globe are likely to warm up so quickly that, by the middle of this century, even the coolest summers will be hotter than the hottest summers of the past 50 years," Diffenbaugh said when his study was published earlier this summer in the journal Climatic Change Letters.

Scientists say the trend towards more hot extremes has already begun. In the U.S., for example, record breaking hot days have already become more common than they once were. According to climate scientist Jerry Meehl, recording breaking hot days used to be as common as cold ones. But in 2000, there were twice as many warm temperature records as cold records in the U.S., and he says that in 2011, so far there have been three times as many.
Go on, skeptics, keep reading. I know it's difficult to get you to think outside your ideological comfort zone, but do try. Here's the paper's abstract:

Given current international efforts to reduce greenhouse gas emissions and limit human-induced global-mean near-surface temperature increases to 2°C, relative to the pre-industrial era, we seek to determine the impact such a temperature increase might have upon the frequency of seasonal-mean temperature extremes; further we seek to determine what global-mean temperature increase would prevent extreme temperature values from becoming the norm. Results indicate that given a 2°C global mean temperature increase it is expected that for 70–80% of the land surface maximum seasonal-mean temperatures will exceed historical extremes (as determined from the 95th percentile threshold value over the second half of the 20th Century) in at least half of all years, i.e. the current historical extreme values will effectively become the norm. Many regions of the globe—including much of Africa, the southeastern and central portions of Asia, Indonesia, and the Amazon—will reach this point given the “committed” future global-mean temperature increase of 0.6°C (1.4°C relative to the pre-industrial era) and 50% of the land surface will reach it given a future global-mean temperature increase of between 0.8 and 0.95°C (1.6–1.75°C relative to the pre-industrial era). These results suggest substantial fractions of the globe could experience seasonal-mean temperature extremes with high regularity, even if the global-mean temperature increase remains below the 2°C target.
Given what happens as a result of extremely hot summers in Australia (bushfires, water shortages) it's also obvious that it's not just extreme temperatures that are the issue.

Thursday, September 15, 2011

Another Texan who believes in AGW

How to talk to a climate sceptic | Environment | guardian.co.uk

I found this a few weeks ago but forgot to post it: a good interview with Katharine Hayhoe, another Texan climate scientist who is firmly on the AGW mainstream science camp, and who goes out of her way to convince the notoriously skeptic evangelical Christian demographic that it is a real problem.

Some extracts:

The third thing I like to tell people is that we do have projections about what the average conditions will be in the future, and so what we can say is that this summer is a picture of what it would be like every summer if we made certain choices regarding our energy sources, and if we reach certain levels of climate change. So for example this summer we've already had 43 days over 100 degrees in Lubbock, which is higher than normal. And if you look in the future this summer is what we'd expect the average summer to be like by the end of the century under lower emissions or by the middle of the century under higher emissions. So we're complaining about this summer, but this could be the average summer within our lifetimes if we continue to depend on fossil fuels....

.....in the southern Great Plains, we are a semiarid environment and we are very water-short already. West Texas is a huge agricultural area and it lies over the Ogallala Aquifer. Since irrigation began in the 1960s, the Ogallala Aquifer has shrunk by over 150 feet in many locations.

Estimates of how many years of water we have left in the aquifer, which has been there since the last ice age, say that as much as two-thirds of the aquifer could be unusable within 30 years. So then you overlay climate change on that existing problem, and you find that with higher temperatures you obviously need more water to provide plants with the same amount of irrigation because evaporation is a factor. We also find that precipitation patterns are becoming more unpredictable, we're getting more heavy downpours and more dry periods in between, which reduces aquifer recharge, because when you get heavy downpours it runs off into the surface water and then obviously you're not getting any recharge. So climate change is exacerbating the problem we have, and it's the same across most of the Southwest, which is very water-short.

She says about 65% of the evangelicals she talks to (I think she is of that brand of Christianity herself) do not believe climate change is real. She has her work cut out.

3-D burn out

Four theories on the death of 3-D. - By Daniel Engber - Slate Magazine

So, the return on the 3-D version of movies has really tanked. It seems, even for a good movie, people are just going along to see the 2-D version.

It doesn't surprise me. It needs to be used much more sparingly.

An over-interpreted study

Testosterone and fatherhood: Are men designed to nurture children? - By William Saletan - Slate Magazine

William Saletan does an excellent job at looking at the ways the "fatherhood lowers testosterone" story has been way, way, over-interpreted by just about everyone.

An important argument in Texas

There is an important argument going on between two resident Texans John Nielsen-Gammon and Michael Tobis at the moment over climate change and "weather weirding" and attribution of events to climate change.

In short, John N-G did a long post in which he argued that the remarkably severe Texas drought and hot summer are (if I can risk paraphrase) not primarily due to climate change. He is no disbeliever in AGW by any means, but he is very, very cautious when it comes to attribution of single events to it.

Tobis, on the other hand, has issues with the whole approach to attribution which can be summarised by his last sentence:

You can't apply small-signal arguments to large signals in nonlinear systems. So please stop it.
And someone in comments expands on this in a way which Tobis basically agrees with:

As Jay Forrester and Ed Deming kept reminding us, people are not good at predicting the behavior of non-linear feed back systems. In particular weathermen and climate scientists study the one weather system, rather than the behavior of dynamic systems in general.

In his classes, Dr. Deming made his students look at the behavior of various systems as the systems went “out of control.” It was shocking how a dynamic system could be “in control” and apparently stable, then suffer some small chaotic event, “go out of control”, and exhibit violent behavior as the system moved toward an new equilibrium. We have been adding heat to the weather system, bumped it out-of -ontrol, and we can expect weather that we have never see before as the system seeks a new equilibrium.

John Nielsen-Gammon missed the point that he has a system that is out of control and that his system is violently seeking a new equilibrium. We can expect ongoing violent behavior until the weather system comes back into control. The studies that he cites all assume that the system is "in control" and that the old rules hold. However, those old rules do not apply to the new, “out-of-control” weather system.
This commenter goes on to point that climate models should be expected to not be good at predicting this.

Tobis' point seems to me to make sense, but I guess we may have to wait for another few years of "weather weirding" to see how it pans out.

UPDATE: Nielsen-Gammon makes a further point in clarification in comments:

We're a degree F warmer because of anthropogenic greenhouse gases. The standard deviation around the best-fit curve seems to be about a degree F. So an event which would have been close to the best-fit curve is one standard deviation off it. Given the lack of rainfall, a temperature which would have been expected to be attained about 16% of the time is now expected to be attained about 50% of the time.

So, this event (i.e., this particular combination of drought and heat) has been made three times as likely by anthropogenic greenhouse gases, with lots of assumptions built in. The least of which is what global warming is doing to our local PDF of precipitation in Texas, which could go either way.

Change the narrative

From a short review in New Scientist:

Do you think that airing your feelings right away will help you through trauma? Are you persuaded that bringing kids to prisons will scare them straight? Convinced that costly, intensive long-term interventions are needed to close the achievement gap in education, curb alcohol abuse and reduce teen pregnancies?

Think again, says psychologist Timothy Wilson. At the heart of his book Redirect: The surprising new science of psychological change is the conviction that many favoured approaches to changing behaviour are akin to "bloodletting" and may do more harm than good. Armed with the tools of experimental social psychology, he argues we can move beyond these untested, "common-sense" views and begin to make some real progress.

Central to Wilson's perspective is the idea that our interpretations of the world are rooted in largely unconscious "narratives" - stories we use to frame the world and that shape our sense of identity - and that these too often leave us unhealthy and unhappy. The good news, he says, is that there is a way to redirect these interpretations "that is quick, does not require one-on-one sessions, and can address a wide array of personal and social problems". Wilson calls this new way "story editing", and in his view it carries enormous potential for efficiently producing lasting positive change.

It sounds like an expansion of Cognitive Behaviour Therapy, but this guy's idea sounds pretty much like what I have thought about on and off over the last few decades.

The "largely unconscious narrative" that you would have suspect causes problems is scientific materialism and its potential to discount free will as being "real" in any objective sense, as well as painting all emotion and thoughts as essentially mere molecular activity with no inherent meaning or purpose.

Of course, there are different ways of arguing that such ideas are not necessarily a consequence of scientific materialism, and biology is such that there is enough pleasure in life for nearly all people that they don't want to end it all because of an intellectual interpretation of what life is like, at heart. But I have long wondered whether people act unconsciously on a internal narrative that, when they get down to it, they are only diverting themselves from reality, do not even have a fundamental control over their own thought processes, and there is no reason for long term optimism.

This theme was also dealt with at length in Bryan Appleyard's book Understanding the Present, which I liked a lot, except for its proposed solution that we embrace Wittgenstein.

Wednesday, September 14, 2011

An old story

Surgeons use toe to replace lost thumb - Health News, Health & Families - The Independent

For some reason, I remember the same operation being done decades ago after reading about it in the Courier Mail. I suspect I may been in high school at the time.

As you were.

Melancholic kid's song

Last night I had to put up with another primary school kid's concert. The novelty of these wears off sharply after each kid has done their first two or three, and in all honesty, some teachers really struggle to come up with good ideas.

When I were a lad, it was simply a matter of each class learning off a couple of songs by heart (at least one of them probably of Irish origin,) standing on a couple of precipitously stacked long benches, and belting them out to the piano accompaniment of Sister Lawrence. (Actually, it may have been a different nun, but Sister Lawrence sticks strongly in memory due to her general reign of terror over Grade 1 and 2. Have I mentioned before that it was one of the most depressing days of my educational life to find on the first day of Grade 2 that I had her again for another year?)

But the point is - I am sure this was a relatively painless experience for the parents, and it was probably over with much quicker than what primary schools get away with now. Primary school teachers be aware: 6 year olds do not do choreography well. You don't do choreography well. Give it up - get them to sing some 2 songs while stationary and get off the stage.

And as for other content - look, even a climate change worrier like me gets sick of every year having one or two classes do some sketch or something or other related to recycling, being kind to the planet, etc. Do something cheerful.

Anyway - where was I? Oh yes: one thing one class did last night was to the Unicorn song (Irish Rovers, 1968.) I hadn't heard it for years, but you would have to call it a bit of melancholy Irish folk for kids. And this got me thinking of other melancholic kid's songs from my childhood, and how the genre seems to have gone away.

Surely the biggest of them all in the genre was Puff the Magic Dragon, which I see was by Peter Paul and Mary from 1963. Being Australian, I associate more it with The Seekers, the group for which every song strikes me as melancholic.

There was another sad sounding kids song that I thought about this morning, but it escapes me now.

In any event, how come we have environmental concern now at least as great as that in the 1960's, but we don't have a sad sounding kid's song about it? Maybe it's just that folk doesn't have the airplay that it used to have in that decade? I mean, it may be unfair, but I suppose I do usually associate "folk" with serious or depressing situations. (It's a bit like the image of Country & Western, I suppose, but my impression is that it is more "pop-y" in both sound and topic now.)

So get to it, songwriters. Some good, depressing songs about carbon dioxide, the rising sea levels covering the old holiday home on the beach, grandma being taken to hospital due to heat exhaustion; politicians too stupid to do anything: there's plenty of material. But I still don't want to hear it at a school concert.

A confusing matter, and a Dr Who complaint

When do gay kids start "acting gay"? - By Brian Palmer - Slate Magazine

Prompted by news of a lawsuit in America to do with anti-gay bullying in a school, Brian Palmer looks at the somewhat interesting question of whether a young child acting outside of "traditional gender roles" is an indication of future sexual identity. In brief:

A hefty pile of research shows that boys as young as 3 years old who break from traditional gender roles have a high likelihood of becoming gay adults. Predictive behaviors include playing with Barbie dolls, shying away from roughhousing, and taking an interest in makeup and women's clothing. (Read the Explainer's take on why boys prefer to play with sticks while girls go for dolls here.) The relationship isn't one-to-one, however, and it's certainly not the case that all boys who love Barbie dolls will later identify as gay. The correlation is much weaker in the other direction: A disproportionate number of boys who don't conform to gender stereotypes turn out to be gay men, but lots of gay men played with G.I. Joe as boys and quarterbacked the high-school football team. Neither does the relationship appear to be as strong among girls. Tomboys aren't as likely to become lesbian adults.
Psychiatrist Richard Green conducted the leading study in this field in the 1970s and '80s. He followed 44 boys who defied traditional gender roles from early childhood to adulthood. Thirty of them became gay or bisexual adults while just one child from a 34-member gender-conforming control group turned out to be gay. The subjects who strayed the most from conventionally boyish behavior were the most likely to be gay. Green's study has since been repeated by other researchers with similar outcomes. (Studies on females show that only around one-quarter of gender nonconforming girls grow up to be lesbians.)

The complicated thing about this is that acting outside of normal gender roles is also commonly seen as a sign of future gender identity issues. Why is it that some boys with this apparent inborn inclination to feminine interests will go on to develop a deep unhappiness with their own body to such an extent that they feel they can't be happy unless they hormonally/surgically modify it, and others will go to be "merely" homosexual, with varying degrees of feminine behaviour as part of that?

Of course, lots of people have written extensively about sexual identity and gender issues, but I am not inclined to waste a huge amount of time on reading about it; I just note that it is a matter that I think is obviously complicated, and far from properly understood.

I think I noted recently here that Native Americans (supposedly) saw cross-gender behaviour in kids as a sign they were a special, virtually holy, "two spirits" combining both male and female spirits. According to this article:

Every tribe watched their young carefully to determine if one of their children were two-spirits. If a boy leaned towards female clothes and mannerism, the tribe encouraged his explorations and vice versa for females.
Given the political use to which such anthropology can be put in the gay marriage debate, there is reason to be a bit suspicious about over-statements on this, and indeed, here's a site that claims reverence of "two spirits" was by no means a universal practice:

According to researcher Will Roscoe, former coordinator of the Gay American Indians History Project, there is no single belief about Two-Spirits among the more than 800 tribes in the United States and Alaska, about 200 of which are not federally recognized. Two-spirits may be respected within one tribe and ostracized in another, while the topic of sexuality could be ignored altogether in yet another tribe.
As I said, human behaviour and psychology in this field is very complicated.

It certainly also makes it a bit of a challenge wondering how one should explain "gay" issues to children. I have not yet had to discuss the "gay" question with my own kids, despite the best efforts of Dr Who to continually bring up gay issues again and again. Surely I can't be the only father in the world who finds this annoying. Even after the departure of the gay re-inventor of the show, Russell Davies, who you could clearly see was inserting a subtext of all types of pan sexual behaviour as being cool and normal, the new producer Steven Moffat, who is not gay, is openly going out of his way to keep introducing gay characters. Here's what he said in an interview:

But also someone pointed out to me [that] in the previous Doctor Who, the first one I had run, there were no gay or bisexual characters and I was sort of slightly appalled. I was thinking, I’m not like that at all. I would never have done that. So I was thinking, “Dammit, it’s the one criticism I’ve ever listened to. Good point, Doctor Who should always be…" It’s not because it’s politically and morally correct. It’s right for Doctor Who, isn’t it? It’s cheeky and off-centered. And fun.
Yeah, well, thanks a lot Steve. You've made it into a psyops program aimed at educating kids on sexuality. Yep, that's why we watch Doctor Who, which is, after all, still primarily a kid's science fiction program, just that it is well enough acted with good enough production values that adults watch it too. And, by the way, although I like the cast quite a lot, its stories are not as good as they were a few years ago, before the Davies decline. In fact, it's nearly time to give it a rest again, I think, after this season.

Anyway, back to kids and the "gay" explanation. I spoke to another father who said he simply answered the question "what's a lesbian" by saying it was a woman who loved a woman. Easy peasy. Maybe that is suitable for an 8 year old, but honestly, explaining homosexuality purely in terms of "love" isn't being realistic with a slightly older kid who has something of an understanding about heterosexual sex.

Part of the problem, as I say, is that it's not clear that adults understand it at all properly from a biological, psychological or cultural point of view either. So I don't care what others may say - it's a tricky issue to explain to a child/young teenager.

More calls for realism

Bishop of Derry calls for end to celibacy in Catholic church | UK news | The Guardian

I liked the last paragraph:

The reordination into the Catholic church of married Anglican priests has pointed up the fact that priestly celibacy is not a doctrine, but a discipline. In 1970, the decline in priesthood vocations persuaded nine leading theologians to sign a memorandum declaring that the Catholic leadership "quite simply has a responsibility to take up certain modifications" to the celibacy rule. Extracts from the document were reprinted in January. Not least because one of the signatories was the then Joseph Ratzinger, now pope Benedict.