Best Of

I’m delighted to have triggered a multi-hour PB thread derailment with my posting of the Paul Johnson article on birth rates.

Now we’ve lost the SeanTs the rest of us need to step up and do more thread derailing.

We've had a few conversations on the topic which have never really got properly going.

My take is its not down to one specific thing, its a multitude, but doesn't have much to do with religion or uni professors. Saying that, the TFR among my friends who went to uni is way lower than those who didn't.

There is no quick fix, some people just don't want kids

My recollection is that the survey evidence shows that women, on average, want one more child than they have.

So we don't have to worry about the people who don't want kids. We have to worry about the people who want kids, and then don't, or don't have as many as they want.

Many years back, an eminent specialist in maternity published an article saying that the medical profession was, in effect, lying to women. That by not making clear the effects of age to the wider public, they were led to believe that having children at… advanced ages was risk free and easy.

He ended up on Newsnight (I think). The lady interviewing him was appalled by his statements - and seemed to think that he (the medico) should keep quiet about it. Because he was damaging hopes and dreams.

Apparently the term "geriatric pregnancy" is now outdated, and "advanced maternal age" is used instead.

I kinda feel like the previous term more accurately conveyed the reality of the situation. And it applies to men too, to an extent.

But the whole way in which careers and employment rights and recruitment, etc, are structured push women into delaying motherhood. We'd need to seriously rethink that if we wanted society to accommodate women having children in their twenties.

I am sceptical...

I did my Obstetrics 40 years ago and I cannot remember it ever being referred to as "geriatric pregnancy," just advanced maternal age, and it always has been clearly taught that fertility drops off fairly quickly from the mid thirties onwards. This is widely known amongst women too, hence the phrase "biological clock". None of this is news to anyone.

Ask any young woman what the problem is and better than evens they will say that they never meet a man who wants to commit to a long term relationship and kids. The problem of extended adolescence is mostly a male one.

What makes men grow up? Running their own home is high on the list, whether that is at 18 or 28.

Not an anthropologist, but I understand that for much of history most people groups had challenges or similar, which were effectively graduation ceremonies where the boys became men, round about 13 or so. That sort of thing is lost in our society.

That's the role of the Common Entrance examination to the English (historically) Public [sic] Schools, surely.

Labour tells councils not to adopt 4 day week working

Sounds like common sense in this economy

Hmm. Depends if it’s about clockwatchers or getting the job done. My contracted week is 36.5 h, over 5 days. But realistically, as an academic, (a) no one is checking and (b) I do more than that most of the time and fail to take all my leave, plus working weekends for recruitment events.

I genuinely think if you set someone their tasks and they have achieved it in four days, then that’s fine.

I know I've said this before, but I work 24-7.

That's 24 minutes an hour, 7 hours a day.

I may jest, but I don't think that is too far off the mark for many of us, once you factor in coffee breaks, loo breaks, chats to colleagues, the odd domestic chore when wfh, and of course dipping in to an online discussion site every so often.

It depends. When I have a complex case I can step up the work rate remarkably and get prodigious amounts done in very little time. But it is exhausting and for short bursts only. I could not possibly work at that rate most of the time. Most of the time we potter along, doing enough to keep the emails answered, the engagements met, the routines followed. It's dull and I can't deny I feel more alive when genuinely pushed. I would just make myself ill if I kept it up for too long.

I suspect that we are not well suited to a steady "7 or 8 hours a day at a steady pace, week in week out, for years". My mental image of a hunter gatherer lifestyle seems much more to have ups and downs at multiple timescales: seasons where there's lots to do and off seasons where life is slower paced, weeks when you're busy and weeks with less exhausting chores, and intense hours and hours spent idling.

Today's lesson.

,I>How did solar get cheap?

Phase 1: 1950-1990s - NASA
Solar was invented in the US by Bell labs and pretty much only used by NASA who needed something very lightweight to power their space assets.

Phase 2: 2000 - Energiewind
The German government passed a law where it guaranteed that if you put solar panels on your roof the German government would pay you a high feed in tariff. Demand exploded.

Phase 3: 2005 - 2015 - China
In Europe German manufacturers could not meet their demand at home and Chinese entrepreneurs saw this fixed arbitrage opportunity and went all in. Chinese companies like Suntech took on huge government loans and built vast factories. Spain and Italy joined Germany with solar subsidies. Because of the price fixing in Europe the market arbitrage held as the solar cell manufacturing output in China exploded.

Phase 4 2015-2025 - Swanson’s Law
Once the big Chinese gigafactories were built, Swanson’s Law kicked in. This is the learning curve where manufacturers compound marginal gains and accumulate 1,000s of solutions to solved problems.

1. Ingots, originally they grew small Si crystals this was a slow batch process. Later they used continuous Czochralski pulling where you refill the crucible whilst the machine is still running. Saving hours of cooldown per batch. They also learnt how to grow huge single crystals that were 2-3 meters long.

2. Wafers, originally they sliced the crystals into wafers using saws. This was slow and turned 40% of the Si crystal into sawdust (kerf loss). The fix was diamond wire cutting, the wire was razor sharp, fast, much thinner than the saw, easier to keep clean and far less wasteful (4% kerf loss). Wafer costs plummeted.

3. Cells, you have to print silver lines on the back of the wafer to collect electricity. Over 15 years silver printing resolution improved and silver use was reduced by 70% whilst also blocking less sunlight. The mirror backing used to be aluminium which captured some solar energy as heat and was lost, so they added a dielectric passivation layer that captured more photons and improved cell conversion efficiency without changing materials...

Ahem: in Phase 1 it was also used in tens of millions of pocket calculators.

I've got one. Hold on while I check. Yes, my Casio fx-451 still works.

I’m delighted to have triggered a multi-hour PB thread derailment with my posting of the Paul Johnson article on birth rates.

Now we’ve lost the SeanTs the rest of us need to step up and do more thread derailing.

We've had a few conversations on the topic which have never really got properly going.

My take is its not down to one specific thing, its a multitude, but doesn't have much to do with religion or uni professors. Saying that, the TFR among my friends who went to uni is way lower than those who didn't.

There is no quick fix, some people just don't want kids

My recollection is that the survey evidence shows that women, on average, want one more child than they have.

So we don't have to worry about the people who don't want kids. We have to worry about the people who want kids, and then don't, or don't have as many as they want.

Many years back, an eminent specialist in maternity published an article saying that the medical profession was, in effect, lying to women. That by not making clear the effects of age to the wider public, they were led to believe that having children at… advanced ages was risk free and easy.

Most of us cannot even go for a jog as easily in our 30s and 40s as in our 20s, seems pretty common sense that many things come with more physical and other risks.

I was just musing to myself the other day, is there anything, anything at all, physical or otherwise, that I'm getting better at? The answer is no (unless you count musing to myself, which I don't think you can).

You could take up something new, then you'll be better over time.
A new language for instance.
I've taken up bouldering as the kids got into it and in the future, when snowboarding is looking less sensible, I intend to be much better at skiing than I am currently

Ah yes, that's true, and I plan to. A craft, I think. I've been watching Bronowski's Ascent Of Man for the first time, what a beautifully written and presented work, and it made me feel downright unworthy. Need to get these hands working. Owe it to my species.

Me, I'd like to take up Ancient Greek. My school performance wasn't good enough to get to grips with the middle pluperfect or the stylistic issues of the [edit] men/de dichotomy.

I did 2 or 3 weeks ancient Greek at the end of 5th year at school. I was supposed to be studying it the following year but I didn't go back and went to University instead. I can remember thalssa meant sea and that's about it. I regret not getting a better education before I focused on law.

Today's lesson.

,I>How did solar get cheap?

Phase 1: 1950-1990s - NASA
Solar was invented in the US by Bell labs and pretty much only used by NASA who needed something very lightweight to power their space assets.

Phase 2: 2000 - Energiewind
The German government passed a law where it guaranteed that if you put solar panels on your roof the German government would pay you a high feed in tariff. Demand exploded.

Phase 3: 2005 - 2015 - China
In Europe German manufacturers could not meet their demand at home and Chinese entrepreneurs saw this fixed arbitrage opportunity and went all in. Chinese companies like Suntech took on huge government loans and built vast factories. Spain and Italy joined Germany with solar subsidies. Because of the price fixing in Europe the market arbitrage held as the solar cell manufacturing output in China exploded.

Phase 4 2015-2025 - Swanson’s Law
Once the big Chinese gigafactories were built, Swanson’s Law kicked in. This is the learning curve where manufacturers compound marginal gains and accumulate 1,000s of solutions to solved problems.

1. Ingots, originally they grew small Si crystals this was a slow batch process. Later they used continuous Czochralski pulling where you refill the crucible whilst the machine is still running. Saving hours of cooldown per batch. They also learnt how to grow huge single crystals that were 2-3 meters long.

2. Wafers, originally they sliced the crystals into wafers using saws. This was slow and turned 40% of the Si crystal into sawdust (kerf loss). The fix was diamond wire cutting, the wire was razor sharp, fast, much thinner than the saw, easier to keep clean and far less wasteful (4% kerf loss). Wafer costs plummeted.

3. Cells, you have to print silver lines on the back of the wafer to collect electricity. Over 15 years silver printing resolution improved and silver use was reduced by 70% whilst also blocking less sunlight. The mirror backing used to be aluminium which captured some solar energy as heat and was lost, so they added a dielectric passivation layer that captured more photons and improved cell conversion efficiency without changing materials...

Ahem: in Phase 1 it was also used in tens of millions of pocket calculators.

Just had a GP appointment where an AI recorded the whole thing and produced the summary for the records.

The GP was at pains to point out that he would review it.

I have a PhD student looking at the tech. The recent NHS 10 Year Plan makes repeated reference to the administrative savings such technology should produce, but at the same time, this year, the NHS and MHRA said that all the products on the market should go through class IIa software as a medical device approval, and none of them have yet. Which means all current usage is in a little bit of a grey area.

Sounds right. He told me it was experimental and asked permission. He also offered, at the beginning, to show me the result at the end, but I forgot to ask.

I’m delighted to have triggered a multi-hour PB thread derailment with my posting of the Paul Johnson article on birth rates.

Now we’ve lost the SeanTs the rest of us need to step up and do more thread derailing.

We've had a few conversations on the topic which have never really got properly going.

My take is its not down to one specific thing, its a multitude, but doesn't have much to do with religion or uni professors. Saying that, the TFR among my friends who went to uni is way lower than those who didn't.

There is no quick fix, some people just don't want kids

My recollection is that the survey evidence shows that women, on average, want one more child than they have.

So we don't have to worry about the people who don't want kids. We have to worry about the people who want kids, and then don't, or don't have as many as they want.

Many years back, an eminent specialist in maternity published an article saying that the medical profession was, in effect, lying to women. That by not making clear the effects of age to the wider public, they were led to believe that having children at… advanced ages was risk free and easy.

Most of us cannot even go for a jog as easily in our 30s and 40s as in our 20s, seems pretty common sense that many things come with more physical and other risks.

I was just musing to myself the other day, is there anything, anything at all, physical or otherwise, that I'm getting better at? The answer is no (unless you count musing to myself, which I don't think you can).

You could take up something new, then you'll be better over time.
A new language for instance.
I've taken up bouldering as the kids got into it and in the future, when snowboarding is looking less sensible, I intend to be much better at skiing than I am currently

Ah yes, that's true, and I plan to. A craft, I think. I've been watching Bronowski's Ascent Of Man for the first time, what a beautifully written and presented work, and it made me feel downright unworthy. Need to get these hands working. Owe it to my species.

Me, I'd like to take up Ancient Greek. My school performance wasn't good enough to get to grips with the middle pluperfect or the stylistic issues of the [edit] men/de dichotomy.

I’m delighted to have triggered a multi-hour PB thread derailment with my posting of the Paul Johnson article on birth rates.

Now we’ve lost the SeanTs the rest of us need to step up and do more thread derailing.

We've had a few conversations on the topic which have never really got properly going.

My take is its not down to one specific thing, its a multitude, but doesn't have much to do with religion or uni professors. Saying that, the TFR among my friends who went to uni is way lower than those who didn't.

There is no quick fix, some people just don't want kids

My recollection is that the survey evidence shows that women, on average, want one more child than they have.

So we don't have to worry about the people who don't want kids. We have to worry about the people who want kids, and then don't, or don't have as many as they want.

Many years back, an eminent specialist in maternity published an article saying that the medical profession was, in effect, lying to women. That by not making clear the effects of age to the wider public, they were led to believe that having children at… advanced ages was risk free and easy.

Most of us cannot even go for a jog as easily in our 30s and 40s as in our 20s, seems pretty common sense that many things come with more physical and other risks.

I was just musing to myself the other day, is there anything, anything at all, physical or otherwise, that I'm getting better at? The answer is no (unless you count musing to myself, which I don't think you can).

Don't be so hard on yourself.
I've noticed a very slight improvement in the quality of your PB posts in 2025.

Thank you, Al. But I sense you're only saying that because it's Christmas.

In the military there's an acronym of the 7 P's - Prior preparation and planning prevents piss poor performance. PB should have some sort of similar acronym for simply sticking your bum in the line of fire.

But, it's gentle fire.

Kearney & Levine (2022): “We are unable to identify any period-specific social, economic, or policy changes that can statistically explain much of the decline [of fertility in the US]. We conjecture instead that the sustained decline in the US fertility rate more likely reflects shifted priorities across recent cohorts of young adults. A prolonged US total fertility rate this low—specifically, a rate substantially below 2—would lead to slower population growth, which could in turn cause slower economic growth and present fiscal challenges. While the decline presents a fairly new challenge to the United States, other high-income countries have sustained below replacement level fertility for some years now and have attempted policies to mitigate that trend. But the evidence on these pro-natalist policies leads us to conclude that incremental policy responses are unlikely to reverse trends in the US fertility rate.”

Bergsvik et al. (2021): “In the course of the twentieth century, social scientists and policy analysts have produced a large volume of literature on whether policies boost fertility. This paper describes the results of a systematic review of the literature on the effects of policy on fertility since 1970 in Europe, the United States, Canada, and Australia. Empirical studies were selected through extensive systematic searches, including studies using an experimental or quasi-experimental design. Thirty-five studies were included, covering reforms of parental leave, childcare, health services, and universal child transfers. In line with previous reviews, we find that childcare expansions increase completed fertility, while increased cash transfers have temporary effects. New evidence on parental leave expansions, particularly from Central Europe, suggests larger effects than previously established. High-earning couples benefit more from parental leave expansions, while expanding childcare programs can reduce social inequalities on other domains. Subsidizing assisted reproductive treatments shows some promise of increasing birth rates for women over the age of 35. Countries that to date have limited support for families can build on solid evidence if they choose to expand these programs.”

Labour tells councils not to adopt 4 day week working

Sounds like common sense in this economy

Hmm. Depends if it’s about clockwatchers or getting the job done. My contracted week is 36.5 h, over 5 days. But realistically, as an academic, (a) no one is checking and (b) I do more than that most of the time and fail to take all my leave, plus working weekends for recruitment events.

I genuinely think if you set someone their tasks and they have achieved it in four days, then that’s fine.

I know I've said this before, but I work 24-7.

That's 24 minutes an hour, 7 hours a day.

I may jest, but I don't think that is too far off the mark for many of us, once you factor in coffee breaks, loo breaks, chats to colleagues, the odd domestic chore when wfh, and of course dipping in to an online discussion site every so often.

It depends. When I have a complex case I can step up the work rate remarkably and get prodigious amounts done in very little time. But it is exhausting and for short bursts only. I could not possibly work at that rate most of the time. Most of the time we potter along, doing enough to keep the emails answered, the engagements met, the routines followed. It's dull and I can't deny I feel more alive when genuinely pushed. I would just make myself ill if I kept it up for too long.