Sex education is a seriously bad idea. Oscar Wilde had it right. We are tampering with the delicate bloom of natural ignorance, putting the very survival of our society at risk.
Thoughts of another natural disaster led me to this horrible truth. I've been wondering of late how many people are actually left in Christchurch.
Plenty of refugees seem to have no plans to return.
Whole suburbs of the Garden City are ghost towns. All they lack are a mournful harmonica soundtrack and a few tumbleweeds blowing down the streets. Amid talk of school closures and the bluster of the rebuild, is there anyone left to rebuild for?
The official statistics slipped out the other day. Christchurch's population fell 4600 in the year to last June, meaning there are now 13,500 fewer people living in the city than before the quakes.
The population used to be 376,700, which means a piddling 3.6 per cent has quit the disaster zone for good.
That figure may be softened by the influx of rebuild workers, but not significantly. So few Cantabrians have fled that you must conclude they are either incredibly stoic or slightly mad, depending on where you sit in the "fight or flight" debate.
I know as a parent that if my two girls had been in that situation, we would have been out of there in our jammies. The new statistics show others share the viewpoint. The 0 to 19 age group in Christchurch has fallen by 9300, and the parental bracket, 35 to 49, is down 5700.
"There was a net outflow of children and their parents from Christchurch after the earthquakes, and fewer young adults arrived for study," says Statistics New Zealand population statistics manager Andrea Blackburn.
In other words, prospective University of Canterbury students have headed to Otago, where the only tremors are self-induced.
Meanwhile, at the other end of the demography, the number of over-50s in Christchurch grew by 2700, as the baby-boomer grey wave surges ashore.
Here's the gnarly bit. Countrywide, the birth rate is abysmal, down 3 per cent and the lowest since 2001. Young people are being responsible - in a typically irresponsible fashion, thinking of themselves instead of reprovisioning the ranks of taxpayers to support our ageing population in their retirement.
Me, for instance.
I blame the teachers, and you can take it as read that the Government does too.
Sex education in schools is far too frank. We can't have hormone-ravaged teens being sensible and realising the consequences of their unbridled lust. Where's the future in that?
Lust is best unbridled. Call me sentimental, but bring back the drunken grope in the grubby back seat of a Vauxhall Velox, and the shotgun wedding very soon after.
Romance is dead. Young couples now plan their nuptials well ahead - long before they have met each other, in some cases.
Double-barrelled persuaders are nowhere in evidence and, even if the bride's father owned a decent 12-gauge, he would likely have to flog it on Trade Me to pay for the grandiose shindig.
For the happy couple, children come well back in priority behind career, big TV and matching iPhones. Women are no longer barefoot, pregnant and in the kitchen as much as Birkenstocked, bloated by alco-pops, and dining in pricey restaurants. It's immoral.
Incidentally, the statistics also show that the spindly Christchurch exodus didn't trek very far. Neighbouring Selwyn District (officially "Sensational Selwyn") is the fastest-growing in the country, followed by Hurunui (blink-and-miss-it old pub, plus Hanmer Springs), Ashburton District (a good second-hand trader, where I picked up a 1920s upright vacuum cleaner because some of my dust dates from that period), Hamilton City (from cow town to now town - which is copyrighted, Hamilton, so don't even think about pinching it), Queenstown-Lakes District (a Hobbit film-crew blip) and Auckland (people can't leave because the motorways are always clogged, so like any trapped creature, they reproduce).
The overall population trend is down if you take out immigration. Deaths were up 2 per cent, and the number of Kiwis quitting the country long term rose 9 per cent in the year to June as the plebs of this new aristocracy vote with their passports.
We are draining away. I may yet live to see tumbleweeds blowing down Brook St.
PS: I'm thinking of becoming an impresario, with two events in mind. The first is a combined choir of Tour de France and BBC officials, who have been very vocal this week. We'll record them somewhere exotic, like Egypt. It's a companion act to the Blind Boys of Alabama, except we'll call them the Blind Boys of De Nile.
The second is a sporting competition. Every America's Cup yacht will be converted from sail to propellers, pedal-driven by Tour cyclists. Weightlifters and certain shot-putters will be plonked down in the bilges for ballast. Child-slave gymnasts can scurry up the mast as lookouts.
The entire fleet sets sail from Auckland for South America, with the hull stopcocks jammed wide open. Thus we rid ourselves of the most sordid sporting contests on the planet in one hit.