Unix is Unix is Unix

From a Hackernews comment on my previous post.

Unix is Unix is Unix. Compared to the diversity that is out there even now, and far more so, to that which was out there 25y ago, all Unixes are the same OS, yes.

They are all one because the differences between them are trivial compared to their similarities. It doesn't matter if the kernel is monolithic or modular, or if the filesystem is case-preserving but not case-sensitive (NT, macOS). These are hidden technical details.

But most people now have only seen Unix and nothing else, so they think that these trivial implementation details -- like what is the default shell, or where are libraries kept -- are important differences. They aren't. They're unimportant decorative details.

When I talk about diversity, let's talk about some real non-xNix OSes I have owned, used, and worked with.

Assumption: shells

Imagine an OS with no shell. No command line at all. Shells are not a given. The idea of typing commands in text at a keyboard, hitting Return to send it for evaluation, getting an answer back, and acting according to that: that is an assumption, and it is one that came from 1960s mainframes.

The slightly more subtle idea that your input is sent character by character, and changing those can interrupt this -- e.g. Ctrl+C to cancel -- that's an assumption, too. It's from 1970s minicomputers, and indeed, the modern version is from one specific company's range: the Digital Equipment Corporation PDP series. The "enhanced" keyboard layout? Not IBM: DEC. The 6-dot-3 then 8-dot-3 letter filename thing? DEC. Filename plus extension at all? DEC.

Alternatives: classic MacOS. Atari TOS/GEM. ETH Oberon. Apple NewtonOS. Psion EPOC16 and EPOC32.

Assumption: configuration held in text files

Config files are an assumption. I have used multiple OSes with no config files at all, anywhere. Not hidden: nonexistent. The idea of keeping config in the filesystem is an artifact of one design school.

Other alternatives to it have included:

- a single global database, part of the OS, not visible in the filesystem at all.

- multiple databases, implemented as different parts of the OS design. One inside the kernel, one inside the filesystem structures of the OS.

- per-app databases, managed by OS APIs. So you don't write files or choose a format: you call the OS and give it things to store, or ask it what's there.

The upshot of these latter two kinds of design is that you get facilities like connecting a storage medium to the computer, and all its programs and data are instantly accessible to the user -- in menus, as associations, whatever. And when you eject a medium, it all neatly disappears again, reverting to previous values where appropriate.

Best example: classic MacOS.

Assumption: there is a filesystem. This is an integrated indexing system that stores data in blocks of auxiliary storage, where they can be found by name, and the OS will read data from them into RAM.

Filesystems are an assumption. Hierarchical filesystems are a bigger one.


All data is in primary storage (IBM OS/400, AKA IBM i.)

Or, media can contain databases, managed by the OS but not accessible by name (Apple NewtonOS).

Or, the primary storage is objects in RAM, and saving to disk is accomplished by snap-shotting entire system state to auxiliary storage. (Example: Xerox Smalltalk.)

Or, the primary storage is lists of values in RAM, and as above, disks are mainly used for import/export and for holding state snapshots. (Example: Lisp machines.)

When you take a long view, in historical context -- not the narrow parochial one of the last decade or two -- then yes, these are all different implementations of near-identical Unix systems. You've seen one Unix, you've seen 'em all.

What we have today is a biculture: various flavours of Unix, and NT. That's it nothing else.

There used to be a verdant, rich forest here. Now, there is just a plantation, with fruit trees and pine trees. You're pointing at apple trees and pear trees and saying "look, they're different!" And at plums (and cherries and damsons and peaches) and oranges (and lemons and grapefruit and limes).

Well, yes they are, a little bit. But look deeper, and there are hard fruit, stone fruit, citrus fruit, nuts. But all deciduous broadleafed hardwoods.

There used to be creepers and vines and lianas and rattan, and grasses and orchids and bromeliads and ferns, and giant herbs, and little parasitic things, some with vast flowers, and mosses and lichens and liverworts.

There was a forest, and it's gone, and no, you cannot persuade me that a neat tidy little orchard with a handful of fruit trees is the same thing.


What is RNA anyway? And why is it so hard to protect yourself against viruses?

[Recycled mailing list post in case it's useful to anyone]

You've heard of DNA, right? DNA is the chemical that is the recording medium for your genetic code and the genetic code of all living organisms, right down to bacteria. You may have also heard it referred to as the "double helix".

Note the "living organisms" part. This is important.

DNA standard for De-oxy-ribose Nucleic Acid.

It is a chain of smaller molecules, called bases. There are 4 of these in most organisms, and their initials are C, G, T and A. A pairs to T, or T to A. G pairs with C, or C to G.

DNA is structured like a ladder: 2 long chains, that twist around each other. The twisting structure is why it's called a helix, and the fact that 2 chains twist around each other is why it's a double helix.

Think of a ladder. The chains are the vertical rails. The pairs of bases are the rungs.

Because in DNA, A only pairs with T, and G only pairs with C, if you split DNA down the middle, each side goes:


or something like that.

Given the way that bases match up, you can reconstruct the other half:


This is a kind of error-checking, and that's why organisms use DNA for long-term storage.  Either half can be used to reconstruct the other.

When a cell divides, an enzyme comes along, splits the ladder in half down the middle like a zip, and then another enzyme reconstructs each side. Result, 2 matching copies, then the cell divides and each daughter cell gets a copy of their own.

To get at the info stored in DNA, an enzyme goes down the ladder looking for a marker for the bit it needs right now, which might for example say AAATTTAAATTT... that means "start here". Another bit later on says GGGCCCGGGCCC, meaning "stop here."  Then the enzype unzips the DNA after AAATTTAAATTT bit and makes a working copy, going along until it gets to GGGCCCGGGCCC then it stops.

The working copy only has 1 strand. It's half the ladder. It is not de-oxygenated. It is just RNA: Ribose Nucleir Acid.

It's for short-term working use, not long-term storage, because there is no error correction. No paired strand. So it's easier and quicker to read -- no unzipping or zipping required -- but it's prone to errors.

Right. That's DNA and RNA. A ladder structure (DNA, think "D for double"), and a working temporary copy, just reduced to half of it (think R for reduced).

Like I said, all living organisms use DNA. They have at least one strand of DNA, and encoded onto it are their genes, which tell them how to grow, how to make their special unique proteins, and so on. The genes are the constriction and operation manual for a cell.

How do you know if a cell is living? Well all living things do a bunch of stuff. They grow and move (even if just by growing, like most plants). They breathe: take gases in and emit different gases. They eat. They excrete the waste from the stuff they eat. They reproduce. They are irritable, that is, they respond to stimuli.

If it does all those -- grow, move, eat, breathe, pee and/or poop, respond and reproduce -- then it's alive.

Viruses are not alive.

Viruses are parasitic genes. They don't breathe or eat or reproduce. They float around, and then if they bump into the right kind of host cell, they get absorbed into it. Most of them have special signalling chemicals on the outside that tell the right kind of host cell "absorb me".

One they are inside, they split open and their genetic payload spills out. Then the host cell reads those genes and does what they say. The genes instruct the host cell to make copies of the virus. In most cases, the host cell is taken over completely, makes hundreds or thousands of copies of the virus until it bursts open and dies, scattering those thousands of baby viruses to infect other cells.

Repeat that enough and the host organism starts spraying viruses around in its spittle or in its pee or poop or sexual juices or whatever. Cold viruses make the lining of your nose and throat itchy so you cough and sneeze, spraying snot full of viruses everywhere. Someone else breathes them in, or swallows them, and they get infected.

The AIDS virus gets into your spunk or vaginal mucus and so it gets right onto the sexual or rectal membranes, invades those cells and starts getting copied again.

Viruses can't even reproduce themselves. They need to get the host's cells to do that for them.

So you can't kill them, because they aren't alive. They don't eat or breathe. You can extract them from someone's blood or snot or whatever, freeze them, and thaw them out years later and they become infective again.

But they mostly do have a complex capsule made of fats and proteins, protecting their genes. Damage or destroy that coat and they can't get into your cells and they are inactivated. They can't harm you any more. Soap does this quite nicely.

Complex animals, like us, have special immune systems that literally learn new threats and can then target them. So you could take just the capsules of viruses, with no genes in, or even a part of the capsule, like the protein spikes, and inject them into an animal's bloodstream, and its immune system goes "hey, that's not part of me, that's alien! Attack! Destroy! Exterminate!" And the immune system remembers this.

So, squirt a bit of the virus capsule into someone, they maybe get a mild fever, but they are now protected from the virus in future. When the real thing comes alone, with that matching capsule, the fore-warned immune system jumps on the invading virus and destroys it and you don't get sick.

Since viruses aren't alive and don't reproduce themselves, they only need a very small simple set of genes. A tiny, stripped-down, lightweight set.

And it's to their advantage to keep changing, so an organism that's seen last year's version with its distinctive capsule with a coat of protein spikes won't recognise this year's protein coat... and the new modified virus gets in, infects the host, gets into its cells and forces  them to start making millions of copies.

An error in copying DNA is called a mutation.

You are complex. You do not want errors in your genes. That would be bad. An error in your genes could give you cystic fibrosis, or muscular dystrophy, or sickle-cell anæmia, or hæmophilia, or a thousand other diseases, and if you don't get it you could pass it on to your children. As a complex organism with hundreds of thousands of genes, you do not want mutations. You just want a mixture of healthy genes, from other humans.

So you have error-checking and correction in your genes. They are recorded in double-stranded DNA for safety.

Viruses are not complex. They are very simple. Mutations are good for them. They don't have a metabolism to go wrong. Mutations help them. Random mutations might give them slightly different capsules from their ancestors, so they can infect hosts that have met their ancestors and are immune to them.

So some, but not all, viruses have switched from using double-stranded DNA to using single-stranded RNA instead. It's much more error-prone because there's no error-checking, but if you are an infective bunch of genes, that doesn't matter. So long as the slightly-mistaken copy of you is good enough to make other cells replicate it and make working copies, that's all it needs.

So transcription errors are very bad for you, but good for viruses that just want to infect you and get copied by your cells so they can infect other complex organisms with all sorts of lovely thick gooey sticky messy body fluids to carry other viruses around in, protecting them, keeping them nice and wet and protected until they can get into a new host and infect it.

And the circle of life continues. Hasa Diga Eebowai!

Nobody really knows where viruses came from. Some are super-simple. Some plant viruses are just little chains of DNA or RNA floating around unprotected, but then, plants don't have much of an immune system.

Some animal viruses are huge and complex. Some bacterial viruses are also super complex, like syringes with legs that are triggered by just the right sort of bacterial cell wall, and actively inject their genetic payload into the bacteria.

Bacteria are single cells, so each is very complicated because it has to do everything: move and eat and excrete and copy itself. They have genes too, in a single ring of DNA. No fancy multiple bundles like we have.

Bacteria have sex, too. They pinch off smaller rings of DNA and swap them. These are called plasmids. They are the way bacteria communicate and exchange genes.

It's possible some of those plasmids went rogue somehow and started making copies of themselves and spreading from cell to cell. That might be where viruses came from.

Multicellular animals and plants are far more complicated. Some of their cells can't survive alone and only live with the help of other, specialist cells.
Some animals and plants are parasites and live inside other animals and plants. If you live inside something else, you can become simpler -- you may not need to eat, move around, protect yourself etc. Your host does that. All you really need to do is steal food from its bloodstream or sap, and have sex so you can make copies of yourself.
Some parasites have become very tiny and simple. They exist just as bundles or threads of a few cells, able only to absorb food, make sperm or eggs, and those sperm and eggs to fuse and make new threads. They get passed on to their hosts' babies.
Well, maybe some of them went super-extreme with simplification and stopped the actual "living" part, and got stripped down just to their genes and a protective capsule.

Or maybe both. Maybe multiple times. It's hard to tell.

Approaching half a year of parenthood (a #projectPrague blog post, by me)

Life has changed beyond anything I could imagine in the last seven or eight months, and I am struggling to adapt.

I decided I was happy over here back in about 2015. I debated selling my house back in Mitcham with the estate agent I’d hired to rent it out. She strongly endorsed the plan. I said to her that I was considering selling, but I’d long thought that I’d hold back until it fetched at least twice what I paid for it – which is to say, £300,000, an absurd amount of money. She laughed in my face and told me that if she couldn’t get £350,000 then she wasn’t doing her job. And after fees, taxes and so on, she did – I got a little under a third of a million pounds for it.
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The older you get, the faster life passes. I’m heading for my mid-fifties and the years jush whizz by in a few subjective weeks. But moving to a new country and starting over certainly slows things down for a while. 2014 and 2015 felt like they lasted a year each, and that hadn’t happened in decades.

But since autumn 2019… wow. A lifetime. Ada’s lifetime.

I hope she gets a lot more than I fear she might, and I hope that I’m there to share the first couple of decades of it.

"Retromancer, or, help help I've been Tuckerised"

That writer of far-fetched fiction Robert Rankin is quite an old friend of mine. I'm in the dedication of one of his novels, but even further than that, I'm a very minor character in another of them.

I recently stumbled across the relevant section when Googling for something, so here, for your amusement, is an extract.

The Savoy Grill quite took my fancy and, as I was certain that it survived the war, I thought that when (or perhaps if) I returned to my own time, I would visit it again to see how much it had changed.

On stage was a band called Liam Proven’s Lords-a-Leaping Jazz Cats. The band leader Liam was an imposing figure in white tie, tailcoat and khaki shorts. There seemed to be a novelty element to the performance, with constant humorous interjections of the, ‘I say, I say, I say, my wife once went to Hartlepool on a charabanc.’


‘Yes, thousands of them.’

Followed by a drum-roll and a cymbal-crash.

‘It is hard to believe, I know,’ said Hugo Rune, taking out a pre-lunch cigar and slotting it into his mouth, ‘but fifty years from now no one will remember Liam Proven.’

‘I will remember him,’ I said to Hugo Rune. And I do remember him well.

The band launched into a number called ‘When Common Sense Walks on a Single Leg, I’ll Wear My Viable Trousers’, and we launched into our soup.
Читать онлайн - Rankin Robert. Retromancer | Электронная ...
Liam Proven’s Lords-a-Leaping Jazz Cats struck up the lively refrain ‘My Love for You Is as Inappropriate as a Grocer’s Apostrophe, Yet Sweeter than a Butcher’s Turn-Up’.

Which was so damned catchy that I knew I would be whistling it for months.

It had seemed such a trifling matter, really. Hugo Rune had scribbled a request onto one of his calling cards and had it passed to Mr Proven. The tune in question that he wished to hear being that ever-popular standard ‘It’s Always Raining Dumplings When You’re on the Gravy Train’. Mr Proven bowed to this request, announced it through the microphone and then turned with his baton to the band. But then a question of tempo arose which somewhat spoiled the mood.

‘It’s Always Raining Dumplings’ is always played as ‘swing’. And as everyone knows, swing is basically a four-four shuffle. As opposed to rock ’n’ roll, which is all straight eights with a back beat, or waltz, which is three-four with an anticipated second beat. Swing is rarely, if ever, in fact never never, presented in five-four. An unnatural rhythm, which although finding favour in the nineteen sixties with such luminaries as Don Van Vliet, brought gratings to the nerves of the bright young things who thronged to the Savoy Grill.

It was the drummer who started the trouble, but is that not always the way?

Liam Proven had prefaced the requested tune with a most amusing jape which ran in this fashion:

Liam: I say, I say, I say, what do you call a fellow who hangs around with musicians?

Guitarist: A drummer.

Somewhat ancient that gag is now, but bright and new back then. The drummer failed to respond with the drum-roll and cymbal-crash and when the song began took to a five-four time signature that threw all his jovial comrades out of tempo. I thought this most amusing and clapped my hands to the beat as best I could. Mr Proven, however, drew his baton across his throat and demanded that the band begin again with the drummer called to order. The band began again, but this time the drummer put down his sticks and took to reading a book.

We did not take too many beers. In fact we were quite restrained. I drove the taxi back to the manse, picking up fish and chips on the way that we might enjoy for some dinner.

And fish and chips in the paper, on your knee in a cosy chair, by the wireless set, is as English as English can be. And I switched on the wireless set to listen to the news. And perhaps catch some popular dance band music of the day. But probably not one led by Liam Proven.


More fun with Czech [#projectPrague blog post]

I have now, apparently, surpassed A1 level. Which is good, but it's taken 5 years of on-and-off studying. My 5th anniversary here was at the end of April. I am finding this hard to believe.

But I am still grappling with the language.

I have a very vague hope that It is possible that my Czech will have substantially improved before it's time to take my daughter to kindergarten, or pædiatrician, or anything. But not very likely, I fear. Czech is savagely difficult and my improvement is glacial.

4 genders, invisible diacritics, invisible letters that aren't written but you must pronounce (which I personally think is worse than English's silent letters), consonants that are sometimes vowels, vowels that are written differently and have different meanings but sound identical (again, IMHO worse than English's 5 symbols for 20 vowel sounds). 7 cases, and a complex system of prepositions to go with them. Only 3 pure tenses (but then English only has 2, plus in the region of 120 (!) modal auxiliaries and moods/modes) but a complex system of "long" and "short", "perfective" and "imperfective" forms and combinations thereof, depending on when it's happening, whether it's instant or over a period, whether it ends at the time being spoken about or continues through it, whether you do it regularly or not, etc.

Anyway. After 5y, I've now moved past ordering a beer and can just about get past using the human-staffed lines in the supermarket as opposed to self-service tills. I can buy a train ticket and order a meal, but if they ask me how it was, it goes pear-shaped very fast.

At 20 I picked up basic German in 3 days of hard work, by way of comparison.

"Just copy the patterns" is what my native friends keep urging me, but they (patterns not friends) are fractal in their complexity. (Well, friends too, I suppose.) Adults native speakers have no idea whatsoever how it all works, they just copy it instinctively.

This is perfectly normal. Native speakers never do. Example: what's the difference between "him" and "he"? Why?

When you make a 2nd order conditional, what tenses do the 2 verbs take, as opposed to a first order conditional? How about 3rd order?

I bet nobody here knows. I didn't before my TEFL course, and I was a professional editor.

Examples in case it helps:

1st order: "If it rains, I'll get wet."
2nd order: "It I won the lottery, I'd buy a Peraves Monotracer."
3rd order: "If I'd studied music as a kid, I'd have played in a band as a teenager."

One thing that is particularly confusing to me is that the patterns in Czech are reused a lot.

For example, masculine nouns end in a consonant.

(It is of course not as simple as that. Masculine animate nouns mostly end in "hard" consonants, masculine inanimate nouns end in "soft" consonants, and there are neutral consonants which can be either.)

Feminine nouns end in a vowel, often "a".

So, um, "muž" is a man, but "žena" is a woman.

But only in nominative case.

To mark a masculine animate noun as accusative, that is the object of a (subset of) verb(s), (maybe, it depends), which is mandatory by the way, you add an "a" onto the end.

So "David invites Martin" (meaning, for a drink), would be "David zve Martina".

[EDIT: yes, as a demo of the trickiness, I got it wrong. "Zvu" is 1st person: "I invite". 3rd person is "zve". *Sigh* Not intentional, and thanks for the corrections. Yes, plural.]

Poor Martin (male name) just got a sex change and is now Martina (female name).

"David invites Martina" would be "David zve Martinu". The feminine noun takes a different ending in accusative, natch.

So you have to be able to do basic grammatical analysis on the sentence to know that the name Martin has undergone declension (and of course which declension, as there are 7 for all 4 genders, a basic 28 forms, but they're usually different for plurals, and there are 2 plurals, one for 2-4 and one for 5+.)

Otherwise, if you don't know that, well, I would assume Martina was a woman, because it's a woman's name.

The patterns overlap. Some declensions take endings _off_ the words, of course, because otherwise it'd be too easy and no fun*. (*I presume this is why they did it**.) (**Yes I am kidding.)

1 car: auto (nominative neuter)
2 cars: auta (nominative plural, not feminine)
5 cars: aut (high plural, i.e. neuter genitive)

And some nouns do change gender when in plural.

Also, uniquely in my experience, verbs and adverbs take gender. Sometimes. Forget that and you give extreme offence when just asking someone a simple question.

I knew Hebrew did this but I didn't know the Indo-European family of languages did.

Recreationally learning Czech feels a bit like recreationally hammering nails into your head.

But I can't just stop, because I live here, I like it here, and I want to be able to speak to my partner in her own language, and maybe appreciate some Czech classics of literature in their original form.

Like Kafka. Oh hang on, he wrote in German. "Metamorphosis" is a mistranslation: it doesn't say Sansa became an insect at all.

Er. The Good Soldier Švejk, then.

As a no more than indifferent hobby linguist, I used to think I knew a bit and had some modest skill in that area, until I came here. I then discovered that some of the way-out stuff I'd heard of -- Mandarin, Vietnamese or Thai tones:

...  Cantonese's swallowed vowels, or Quechua's evidentiality ( ) -- that's big-picture stuff.

But the Slavic languages... sheesh. They're our near-neighbours, culturally and linguistically they're siblings. And then they throw gendered verbs at you?

I mean I regularly call my girlfriend a man.

Czech doesn't have a verb that means "to like". It has to love, but to say you like something, you say:

Mám rad pivo.

(I) gladly have beer, or (I) have beer gladly.

The verb encodes the identity of the person so they discard the pronoun, like Spanish.

But adverbs take a gender. I can't do conditionals yet, so I don't know how to say "would you like a cup of tea?", but if I said to Jana, "like a cup of tea?"

Más rad čaj?

That sentence encodes 2 pitfalls. "Máš" is the intimate form and I would be offensive if I said "Máte rad čaj?" because that also means "(you) like tea?" but it is the formal form for someone you don't know
very well.

But both also say "like a tea, Mr Clearly Male Man?"

To a woman I must say "máte rada čaj?" or "maš rada čaj?"

I'd never met anything like that before, from French to Japanese, and I regularly forget.

This is after easy beginner stuff like the tons of "accents" they put on consonants. I only knew how to handle accents on vowels: fiancée, naïve, etc. The French cedilla in Français and garçon honestly doesn't seem to make any consistent difference.

But Czech has š for sh, č for ch and so on, plus ť for ty, ď for dy, ň for ny -- but they usually don't bother to write those because you must always say ty if the t is followed by i, for example. (Except when you don't, such as foreign words.)

We western Europeans take so very much for granted, and even other white, broadly Christian Europeans have profoundly different languages to us. And if Sapir and Whorf are right, then that means a very different world-view.

Which has made me re-assess so many things. How the different languages like the many African and both North and South American work, and what it's like to see the world through them. What it's like to have to live and work and learn in Spanish or English, languages which lack even simple basic stuff like stating how true you  judge something to be.


The Patchwork Man [#projectPrague]

Back in October last year, a friend of mine was visiting Prague on a work trip. We met for a few beers. Literally three I think.

Unfortunately, on my way to the Metro after walking back to his hotel with him, I tripped and fell going into the station. He was very helpful and paid for a taxi home. However, as it crossed some of Prague's ubiquitous cobbles, I moaned in pain. 

The taxi driver asked if maybe he should take me to hospital, rather than home. I reluctantly agreed. I asked which hospital.

"Karlovo Náměsti," he said.

"But I live there. I thought you were taking me to hospital!"

"I am." 

"But which hospital?"

"Karlovo Náměsti."

"That's where I live! Where is the hospital?"

"Karlovo Náměsti."  

There was a hospital in my square and I didn't even know.

With the help of a porter who spoke no English but a little German, I found the emergency department. They attempted to relocate it for an hour which was excruciating, damaged the joint extensively and ultimately failed. They had to do a nerve-block and then it slipped in easily.

They kept me in overnight. That was "interesting," but the some of the nurses spoke quite good English and they were very helpful. They even provided  a vegetarian lunch on no notice at all.

I had to wear an orthesis to secure it. A week later, I rolled over in bed (in the orthesis, note) and it dislocated again. I hobbled across the square to the hospital (walking with a dislocated arm is extremely painful), in my pyjamas.

Rinse and repeat. At least, since it  was 7AM, I hadn't eaten or drunk, so they could do a general anæsthetic and put it back in with less of a fight.

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I'm an alien, I'm a legal alien [sort of #ProjectPrague blog post]

[Patched together from 2 mailing list comments. Apologies for any remaining disjointness.]

The more about Brexit I read, the commentary, the discussions, especially from pro-Leavers, even the most cool-tempered, moderate, reasonable ones... it's the kind of indiscriminate nonsense and hostility that makes me glad that I no longer live anywhere on that septic island, and hope that I never have to return on a permanent basis.

I mean, sure, Moravians don't like Bohemians, while Bohemians regard Moravia as an empty tract of wasteland. Moravians sometimes also have a very slight distrust of Slovakians because apparently Slovakia sided with Bohemia about something, a thousand years ago. Something like that.

I don't have to care, because I don't belong to any of them. It's all equal to me.

Technically, legally, I was born in Liverpool. The town containing the hospital and my parents' home, 15 miles away.

Then the town I was born in was rezoned into West Lancashire. Does that make me Liverpudlian or Lancastrian? I don't care, my family left both forever in the 1970s and I never wish to return for more than an overnight stop, ta. There's nothing there that I associate with, no particular pleasant memories, no childhood close friends.

The Lancastrian accent is a damned sight more appealing. However, I can't fake it well enough to fool Lancastrians, whereas I can fake Scouse well enough to pass -- at least if I'm drunk enough.

Normally, I speak RP.

But in London, I was a Northerner, blunt to the point of rudeness. I lived there for 22 years and it's far more "home" than Liverpool or Lydiate or Ormskirk or anywhere on the Isle of Man.

Back in the North West, I was a sellout who moved to Mordor. Now, to my Moravian friends, I'm a sellout who moved to Mordor.

When I visited Newcastle or somewhere, or to my mates from around there, I'm not a Northerner at all.

To be frank, to me, it's all tiresome shite.

I'm British by birth, but I don't miss it. Bitter, mild, porter, golden ale; salt'n'vinegar crisps; good chips. You can keep everything else. I'm English but I found Scotland a lot more appealing, except for the weather.

I'm Irish by adoption but can't afford to live there.

I'm Czech by residence but I'm never going to master this language. I'll never belong.

So what does that leave me? I don't really care. I'm free. I can go where I want. For now, I like it here. I hope to live in some other countries and sample some other cultures.

All this partisan stuff, of belonging somewhere and not liking anywhere else because it's Foreign, is alien and ugly and iniquitous to me. Even if it's a harmless bit of fun, it's the sort of thinking that leads to football mob violence, Brexit and war.

I will have no part of it.

I don't really "get" regional pride. I mean, yes, I am aware of the "Northern bluntness" thing and I don't mind that at all, but with a childhood shuttling between outer Liverpool, Nigeria, inner Liverpool, Southport, the Isle of Man and then London for unversity, my accent went all over the place and it taught me that it was useful to be able to adjust said accent a little bit from one region to another.

I don't feel I particularly belong anywhere. I feel very faint nostalgia for early childhood in Lydiate. Much more for Nigeria. I hated school, loved university, so that gave me a fondness for the south east, and when I was able, I headed back there.

Some 22 years later, life in credit-crunch London was getting shitty, for a 40something techie... so when the chance of a job in Brno came up, I leapt at it.

Friends have gone "oh that was so brave!" or "I could never do that!" or "I could never live in country where I don't speak the language!"

It was no big deal. It really genuinely wasn't. Emptying the house was hard work, and I owe a couple of friends who helped a lot. But surprisingly few of them. The paperwork for renting and then actually selling it was a pain. It involved a few flights and inconvenient train journeys. My last 3 or 4 days in London, I rented a car, something so dramatically atypical for me it's hard to describe. I dislike driving, I dislike cars, but I needed it.

So, you know, a few days' hard work here and there, and bam, I was in South Moravia wondering WTF I was doing. But then the new job started and about 3 days later I was too busy to worry. So I haven't done, since then.

It's all been great. A fun roller-coaster ride.

I have a friend who's very proud of the fact that all his life he's lived within 3 miles of where he was born, in a suburb of Nottingham. I've stayed there a few times. Nice enough place. I've been to a few SF cons in Nottingham; I quite like it.

But that sounds like some mediæval hermit choosing to live on a platform on top of a pillar to me. Even the thought, the idea, fills me with dread. I'm not a scouser or a Londoner or an Englishman. I happen to be British. Now I'm Irish too. I happen to live in Bohemia and it lives up to the adjective. I like it here. I fancy living in Paris for a few years at some point, and maybe Berlin, and possibly Asia for a while, and maybe Latin America at some point -- I want to polish up my meagre tatty Spanish.

I don't and won't belong to any of them.

I suppose I feel that feeling that one belongs to somewhere, and believing that the place one belongs to is better than other places, is iniquitous. It seems fun, a harmless joke, but to me, it feels similar to "harmless jokes" about nig-nogs or chinks or nips. It's not meant as such but it smacks to me of deeper feelings that I regard as harmful and dangerous, although I must stress here I am NOT imputing such feelings to anyone here!

I just find the whole area, the whole notion, a bit distasteful. Most people seem to think it's fine, it's nothing.

Some of my closest friends here are a Romanian woman, a Dutch guy, a couple of American guys. One was a French man of Caribbean extraction, but he moved away. One of the Americans is married to a Czech woman, but he did that after he'd been here a decade, it's almost incidental.

We all share this rootlessness. We don't dislike our homelands, but by the same token, none of us seek out the company of our countrymen over here. In fact we vaguely avoid it.

There's another sort of foreigner here. They are often people married to locals who they met soon after they arrived. They mostly have kids.They integrated a bit more into Czech society and they don't socialise with foreigners.

I think of 'em as rubber Czechs, har har. I don't quite get what they are doing or try to do either. I'm not Czech, I'll never be Czech and I don't intend to try to be a fake Czech. I don't expect to live here the rest of my life. I have lots of Czech friends, I sometimes go to Czech events and so on -- I try not to be a resident tourist. But I'm a foreigner, an immigrant worker, and I don't see any point in trying to hide that.

When I was a schoolkid in Southport, we did a day trip to a spinal-injuries hospital with a big childrens' unit. I don't remember where. I briefly tried wheelchair football. It was terrifying. The wheelchair-using kids seemed suicidal: as if they were thinking "I'm already broken, it can't get any worse -- banzai!"

I found it very interesting. I was too young to think "ooh, everyone should spend time in a wheelchair."

But I did, for a while, in 1994. Not from choice, of course. After I binned my ZZR1100.

It was immensely educational. I briefly belonged to another section of society, and I learned some things that were surprising to me. I saw how another part lived and some bits weren't good and they weren't to do with the actual physical disability at all.

Everyone should do it.

Well now I sort of feel that everyone should live abroad for a while too. Somewhere far away and a bit culturally different. Somewhere they don't speak the language and somewhere there are not many of their countrypeople around them.

I'm not saying it harms people not to do this. There's nothing wrong with my mate from Nottingham. But by the nonexistent gods, it's been good for me. I should have done it a decade earlier.

I reckon it'd be good for everyone.

Loving where you're from is fine. Thinking it's better than anywhere else is not fine. By and large, so long as you're not in a warzone or a famine, nowhere is better than anywhere else. And very definitely no people from anywhere are any better as a group, or any worse as a group. There are good and bad people everywhere and in about the same mix, I suspect.

The late great Professor Stephen Hawking

People are exchanging reminiscences online. I'm afraid I only have one.

I had collossal respect for the man, his achievements, his astounding determination. Not only did he do a huge amount for physics, but also for perceptions of disabled people. He appeared in the Simpsons, the Big Bang Theory, a number of adverts, and via one of them, a Pink Floyd album. Pretty good showing, really.

For me, he put me in mind of Dr Dan Streetmentioner.

Dr Streetmentioner is of course the author of The Time-Traveller's Handbook of 1001Tense Formations, as documented by the equally late great Douglas Adams.
One of the major problems encountered in time travel is not that of becoming your own father or mother. There is no problem in becoming your own father or mother that a broad-minded and well-adjusted family can't cope with. There is no problem with changing the course of history—the course of history does not change because it all fits together like a jigsaw. All the important changes have happened before the things they were supposed to change and it all sorts itself out in the end.

The major problem is simply one of grammar, and the main work to consult in this matter is Dr. Dan Streetmentioner's Time Traveler's Handbook of 1001 Tense Formations. It will tell you, for instance, how to describe something that was about to happen to you in the past before you avoided it by time-jumping forward two days in order to avoid it. The event will be descibed differently according to whether you are talking about it from the standpoint of your own natural time, from a time in the further future, or a time in the further past and is futher complicated by the possibility of conducting conversations while you are actually traveling from one time to another with the intention of becoming your own mother or father.

Most readers get as far as the Future Semiconditionally Modified Subinverted Plagal Past Subjunctive Intentional before giving up; and in fact in later aditions of the book all pages beyond this point have been left blank to save on printing costs.

The Hitchhiker's Guide to the Galaxy skips lightly over this tangle of academic abstraction, pausing only to note that the term "Future Perfect" has been abandoned since it was discovered not to be.
I have a vague feeling that one version of the guide said everything after page 75 was left blank.

By a staggering coincidence, that is exactly how far I got through A Brief History of Time... and from what I've read, I got further than most readers.

I think it was regarded as the least-actually-read bestseller in history until Piketty's Capital.

I guess I shouldn't feel so guilty, really.