Cambridge Computer Z88

Cambridge Z88

The mid-1980s: After the QL computer and the C5 electric vehicle debacle, the world waited with bated breath. What would Sir Clive Sinclair do next? Would a portable Super-Spectrum emerge? As it turned out, Sinclair and the brand was sold to Amstrad and any interesting developments got the axe. Or did they...

Cambridge Z88 from 1987 was Sir Clive's last hurrah in the computer markets. Well, obviously Clive had little to do with the functionalities of the computer, here credited to Protechnic Ltd., Colton Software Ltd., and Operating Systems Ltd. BBC Basic is courtesy of R.T. Russell (Originally by Sophie Wilson). 

Still, the computer continues Clive's focus towards smaller and portable computers and is supposed to have its roots in the Sinclair Pandora laptop concept.

For a short while, Z88 might have been a success in its own niche, but far from the kind of hit Clive would have needed at that point. What might have been game changing in 1984, was less so in 1988. At least Amstrad came up with their Z80-based NC100 as late as 1992!

Perhaps not the strongest slogan...

I saw pictures of the Z88 in the computer magazines around 1987–1988 and would have been excited to have a go at it.

Cambridge Computer's friendly approach to the Speccy press invited a curious kind of brand loyalty. This might have backfired a little, as the magazines were showing healthy scepticism towards the usual Sinclair hype and promises. Still, the most loyal Z88 fans were likely to be Spectrum aficionados.

By the way, magazines had apparently received a note from Amstrad dictating that this new machine from Clive should not be referred as a "Sinclair", a matter cheekily addressed in Sinclair User #61.

The Finnish press was positive. At least MikroBITTI 11/1988 described it as a "dream micro" and felt a Z80 chip was sufficient for typing on the go. It's interesting that the importer was PCI-Data (Commodore), not Hedengren (Sinclair).

Now, the definitely Sinclair-style appearance and the self-contained nature of Z88 makes it attractive to me. BASIC, spreadsheets and word processing, what else do you need in 2023?

Swedish version.

First impressions

Physically the computer fits into an A4 footprint. It is reminiscent of some of the sketches from Alan Kay's Dynabook concept, except the screen is not nearly as tall. I know a plastic protective cover exists, it would have been nice to have.

Overall, there's a little nod to the QL styling, it's a Rick Dickinson design again and as a physical object it is very attractive. All the flaps, buttons and openings are precise, meticulously placed. Because of the lightness it does give a somewhat flimsy impression, I wouldn't bend the plastic case too much.

The transparent, numbered door over the card slots is an especially juicy little design detail, hidden at a corner where it's barely visible.

The keyboard was at first a cause for alarm, as it harks back to Sinclair's rubbery explorations. Worry not, typing is much better than on the Spectrum, perhaps even better than the QL. The keys are extremely silent and responsive enough, a tad too sensitive though.

The RS-232 port, fortunately not telephone-style

The space key feels a little weird, as it does not depress entirely but just squishes down at the spot you touch. Instead of Control and Alt keys, there are the original Diamond and Square keys.

The power is turned on and off by pressing both the SHIFT keys. And it's not a hard power on/off, the computer goes into standby and you can continue working from the same spot after turning it on.

A few times I was able to accidentally press both SHIFTs when trying to get my fingers around typing those silly :RAM.1/ device identifiers. Remember to set the default device from Control Panel.

The four AA batteries supposedly give 20 hours active use, or about a year in standby. This was one of the most doubted specs in the contemporary press, and Rakewell's site lists more accurate numbers. The real standby battery life is more like few months, depending on the battery type and RAM configuration. 

It's sensible to use the PSU and when the batteries need changing it better be connected. There's a small window of time in which the batteries can be changed without a PSU, but who knows the state of the capacitor after 35 years.

PSU connector, tiny reset switch and the contrast adjuster

The display is a surprisingly okay LCD-type screen, but without a backlight it's rather sensitive to lighting conditions. The resolution is 640*64, which is good enough for editing 8 lines of text.

But thinking about it, the display has less pixels than a ZX Spectrum! (256*192=49152 versus 640*64=40960) The pixels come in three intensities, though.

The CPU is a low-power Z80 variant, which at 3.2768 MHz should be a tiny bit slower than the Speccy.

There are three slots for RAM/ROM/EPROM cards. My Z88 fortunately came with three 128K RAM expansions. This gives a decent 384K extra memory on top of the measly 32K built-in, although one extra 128K might have been enough for me. Apparently the computer is really crippled if there's no extra memory present.

Two ROM/RAM slots and the EPROM/ROM/RAM slot, behind a transparent door.

Obviously the Z80 chip can't handle more than 64K directly, so there's a memory manager that seamlessly banks in memory.

The RAM has to be powered, which is a potential problem. If you remove one of the cards, the Z88 will become unresponsive and needs to be soft reset. Doing this will obviously empty the current memory and any suspended applications.

However, when removing card 3 the files "saved" in card 1 were still preserved. Using the reset key with the card door open will hard reset the computer and all the RAM card contents.

One of the ports takes in an EPROM cartridge, which can be used for storing data more permanently. Technically, only ROM cards can be used to add new applications, but later developments have made it possible to run apps from RAM. From around 2000–2010 there have been Flash memory cartridges for permanent storage instead of the EPROM solution.

A 128K RAM Cartridge

The cards are cute and remind me of Microdrive cassettes, although bigger and with no tape at sight. From the other end you can see an edge connector.

There's a fold-out stand in the bottom of the Z88, something I didn't discover until few hours of use.

OZ, PipeDream, BBC BASIC, apps

There's a plethora of tiny functions and apps built inside the 128K ROM. The computer has BASIC and PipeDream, a hybrid word processing/spreadsheet/database package. There's a calculator, diary, VT-52 terminal and a serial importer/exporter app. The Filer can be used for managing stored files and provides an interesting way of executing text files as key-command scripts.

Using INDEX key you can enter the app menu at any time and choose an app. If there are already instances of apps launched, they will be listed at the right side of the menu as "suspended activities". So I can continue a BASIC project or text editing exactly from where I left it the last time.

Some of the built-in apps

The system is not as graphical as the menus would make it appear at first. Some of the option and control panel screens are messy, but fortunately don't have many items in them anyway. When selecting files within apps, you may be prompted to type in the filename, with no assists provided. 

There's a HELP key, but apart from PipeDream it doesn't provide much information. Removing programs from the suspended activities list is fun: You have to type KILL after pressing the diamond key.

The Z80 chip chugs along slowly, so the menus aren't especially fast and neither is PipeDream the main software package. In QL style, the font is 6x8 rather than 8x8 to make more text fit.

I was tempted to write this blog post using PipeDream, but after sketching some paragraphs I gave up. I found I could type in fast enough, but making any changes to the existing text is a little too cumbersome. Maybe another time.

The peculiarities and compromises of the editor often arise from the needs of the integrated spreadsheet functionality, line splitting and moving between lines doesn't work exactly like in a modern text editor. Still, for a 1987 tiny portable computer it is quite an impressive package.

The software suite and the OS become better the more keyboard shortcuts you learn. Just as I've saved a text file, I can jump over to the RS-232, transmit it, and then press ESC to get back. Most of the important shortcuts for text editing are listed below the screen and this really is helpful. 

The lack of rows on screen is slightly alleviated by the overview map at the right side of the screen with one character represented by one pixel. This is the earliest editor where I've seen this, it's quite common in modern code editors like Sublime Text.

PipeDream's handy map

Moving around using TAB and shift-TAB, you can insert "expressions" into the positions and have the software calculate sums etc. Elsewhere you can just continue typing text without being limited to the cells.

The calculator is the most visual function in the device. It's clumsy and simple, but does have the virtue of being available even if you are in another program, by using [SQUARE]R. The clock and calendar can be invoked in a similar manner. Together with the suspended task switching, it gives a tiny sliver of sophistication without multi-tasking.

Instead of Sinclair BASIC, there's the BBC Basic, which seems a little funny considering how Sinclair and Acorn used to be in competition. The BBC dialect is pretty famous for its structuring and it even has an inline assembler. 

The manual also provides an interesting hack to use the Filer "CLI execute" function to tokenize ASCII files by first opening the BASIC and then virtually typing rest of the plain text file contents in as keypresses. Put AUTO as part of the macro and it doesn't even need line numbers. Ingenious or kludgy? At least this means PipeDream can be used for writing program listings, as BBC Basic can use named procedures.

The "CLI execute" can also be invoked through Basic, so a command can launch another app and type in commands there. The freedom given to the user is really mind-boggling, and even if you don't want BASIC or assembler, PipeDream is quite versatile in itself.

A BOOT.CLI can be used but on the non-upgraded Z88, this sadly only works from an EPROM. This could, for example, make the computer boot into BASIC after reset. However, seeing as the computer is either on or in standby, the most sensible use for the boot file is to manage preferences after reset.

I experienced a considerable slowdown at one time, especially after playing with these CLI execute functions. Typing with PipeDream was no longer comfortable, even if I had cleared all internal RAM of files and KILLed all unnecessary apps. I reset the computer and all was fine again. Perhaps there was some garbage management problem.

The BASIC has no graphics commands, I guess because it would be wasteful to hold a pixel buffer. I see the author of BBC Basic has created a patch that adds the graphics commands, though.

There are more recent versions of the operating system, done by enthusiasts after Cambridge Computer shut down. Some of the tiny problems I encountered might be fixed by upgrading the Z88.

Colton Software still makes PipeDream, not for the Z88 mind you!

A few thoughts at this point

Much like with the Sinclair QL, the Z88 felt a little iffy at first but I became more and more intrigued with the platform. The computer invites learning to use it better, finding shortcuts and tricks as you go along.

The Sinclair QL already provided a word processing and spreadsheet suite, but the execution was marred by hardware decisions. In a way Z88 continues this fixation but doesn't have similar problems.

This focus on business productivity means that many cool things are left out, such as graphics or sound. There's no mouse, but a computer like this does not really need one.

There's an estimate of some 60000+ units made.

One can't really blame Cambridge Computer for not succeeding, as far as I know no-one really scored it big with these small form factor computers in the 1980s. Typing on the go was a niche thing and buyers more likely put their money into more powerful computers, rather than tinier computers. Although 6 million TRS-80 Model 100 units sold, if true, is impressive. 

I could compare my tiny 8-bit computers Canon X-07, Atari Portfolio and the Z88. It's possible that because of the huge keyboard and the comprehensive feature list, the Z88 beats the others in terms of usefulness and features for the 2020s. Obviously Atari is the smallest of the trio, but without any programming language built-in, the fun factor is lower. I guess without extra memory Z88 would be limping too, so the comparison is not so straightforward.

Traveling silently

I might eventually look inside, if only to peep at the capacitors and any signs of dust or grime. I postponed this as it looks like a couple of screws are under the rubber feet and one is under the serial number label. The LCD and its ribbon are also notoriously fickle.

Serial transfer

I quickly built an RS-232 adapter cable for my USB-COM device, and it worked well enough. One brainfart had to happen though, using the wrong gender at the Z88 end of the cable. Well, gender-changer to the rescue. 

I can already say that sending data from Z88 at 9600 rate is ok, but it is hopeless at receiving at this speed.

Beam me up

Minicom was sufficient to test the connection.

If the device is called ttyUSB0 on Linux, then:

minicom -D /dev/ttyUSB0

I then set minicom to 9600, 8N1 (Parity none).

At the Z88 end, I launch the Control Panel (Square+S), set Parity None and Xon/Xoff to No.

Then I can use the VT-52 terminal in Z88 to send and receive characters and the Import/Export app to transmit and receive files.

With some more work I was able to store some of my first PipeDream jottings for historical purposes. I already feel more safe about resetting the Z88.

Some links:

Crash! magazine and Simon Goodwin on Z88: https://www.crashonline.org.uk/39/z88.htm

Rakewell has kept the name alive over the years: http://www.rakewell.com/z88/z88.shtml

More resources: https://cambridgez88.jira.com/wiki/spaces/welcome/overview?mode=global

Pictures of the insides at Old Crap: https://oldcrap.org/2019/10/28/cambridge-z88/

Shortening the kickbike

One of the reasons for buying this particular model was it looked like it could be modified easily.

Previously, I have already removed the wooden deck addition and shortened the handlebars. Now I had something bolder in mind.

I have been thinking of two ideas. One was to remove the "wings" at the side of the deck, possibly reducing some weight.

The other idea was to make the deck shorter, both to reduce a little weight and improve the maneuverability (hopefully). This seemed more interesting, and I was a little worried removing the wings might compromise the strength of the box and make it a little too narrow.

I had suspected the outer case could hold inside a relatively large "inner case", but it turned out the part that goes in is much smaller than I thought.

Sketch, not to scale

There are 4 bolts on top, 4 at the bottom, and then 2 at the sides.

Obviously one of the side bolts had to be gloriously stuck, so I had to waste time in removing it. After ruining the hex, I realized I could file the bolt into a more rectangular shape and use a spanner to turn it.

After some nudging, the block connecting the stem to the chassis falls out. The portion that goes inside is only 27 millimeters deep, and the shape is irregular. It is quite hefty.

The connecting part

I could have taken better photographs, but maybe the opportunity will yet arise.

Then began the process of measuring and deciding how much to cut away. Peeking inside, I could see there's virtually nothing at the front 14cm part of the compartment.

I eventually chose 6cm as a suitable amount. There is a hatch at the bottom of the chassis, and if I cut for example 10cm, the hatch edge would be rather close to the front. The other thing to worry is the 28mm radius cable hole in the side.

The 6cm should be significant, but this also leaves some empty space inside the box.

Not all the space is used up.

I was a little lazy and traced the lines around the box using a vernier caliper adjusted to 6cm.

After that, I started sawing with the hacksaw. This is a boring job and I split it into two sessions for two different days. Together it took more than an hour with some pauses.

I'm not very skilled with the hacksaw, but I managed to do it accurate enough. Patience is key, otherwise it's easy to start doing things too hastily, resulting in a mess.

Removing 6cm from the front...

The case is some sort of aluminum alloy, which is quite soft to cut and drill. 

Only afterwards it occurred to me the process could be generating some fine grain aluminum dust, apart from the stuff I could obviously see.

One thing to look when cutting a profile like this is to have an eye at where the other part of the saw is moving. While focusing on the actual cut, the saw might be stealthily ruining another part of the cut.

The part, cut loose

Compared to sawing, the drilling was quite easy and fast. I took the measures from the original piece, and just transferred these over to the desired positions. 

I used 2mm drill for making pilot holes, then an 8mm for the actual sizes. I used ridiculously low speeds here, probably only a few revolutions per second.

Drilling new holes

The original holes were not perfectly round, especially the side holes are more like very short routing lines. I just hope there isn't a really precise logic behind that, possibly just a result of using an automatic router.

The results

I believe shortening the deck improved the drive-ability of the kickbike. It shouldn't be a huge difference, but I think turning tighter corners is a little less precarious.

The distance between the wheels is now shorter than the Voi, which is something of an accident as I had previously measured the distances incorrectly. It might have been nice if the wheels have the same distance. Well, the subjective experience should be more important than the measures.

But did I get rid of any weight?

Carrying the bulk might be slightly handier because of the smaller dimensions, but it's such a small difference it cannot be really felt as weight difference.

I'm going quantitative

The cut part really was one of the lightest things I could remove, so the effect on that front wasn't that great. The cut aluminum part weighed only ~245 grams. Taken together with the plastics it's a little closer to 370 grams.

To put things into perspective, what things weigh:

The 6cm aluminum alloy part: 244g
The 6cm aluminum alloy part and the plastic parts together: 372g
The plastic parts: 134g
Wallet: 160g
Smartphone: 300g (!)
All the keys in my pockets: 145g
Bike helmet: 323g

The kitchen scale measures fluctuate a few grams so the values are not very accurate.

At least the removed material compensates for wearing the helmet!

It's obvious I could lose more by leaving my phone, wallet and keys home.

Measuring the cut out block against the 244g weight pointed to a material density of 2500kg/m3.

Apparently aluminum alloy density isn't likely to be lower than 2660kg/m3, I might be persuaded to believe my measurements are off. The piece has holes, the scale isn't accurate, and so on.

As a ballpark estimate, the central chassis metal part does not weigh more than 3kg. (The battery and other stuff inside are probably heavier.)

I've yet to measure the weight of the entire kickbike (Probably around 28kg originally) so I'm not sure what kind of percentages the removals represent. Also, taken together with the driver's body weight it means very little in the entire system. 

The next step is to cover the openings. I could even cut some more material and try to fit the indicator lights back the way they were.

Sony WH-1000XM5

From outside

Took the plunge and bought noise-canceling (NC) headphones. I've had them for a while now so thought about commenting on the experience.

One of the city sub-artery roads is just outside the window from where I sit, and it can get a little wearisome at times. With these headphones on, this traffic noise is cancelled almost entirely. 

I could even sit with the headphones on without any music and not hear much of the outside world. But it's obviously better when using at least some music or sounds, as otherwise I start to pay attention to even tiniest hissing or the occasional minor pop/click coming from the headphones itself.

Yes, if you are entirely allergic to the idea the headphones might produce some additional sound, and find yourself actively looking for such sounds, then it might be a deal-breaker. But I've never really noticed it when playing music or watching movies.

From inside

Almost needless to say, with the NC I can't hear minor things like computer fan noise, air conditioning or the washing machine from few rooms apart. Singing practice in the apartment is not cancelled though, but it becomes subdued and louder music from the headphones will cover it.

If the headphones are in a passive (non-powered) mode, there's audio but it's not very good to be honest. The active mode will deplete the battery but I've found the need to recharge about once a week even with daily use. The charging is quite fast.

The ambient mode allows outside noises through, but I haven't tested it much. Likewise, testing the invisible microphone hasn't been a high priority as I am more comfortable with the headset style in video conferences, a real mic gives me more confidence. 

The power and ambience buttons.

I press a tiny button for a while to activate the headphones and the noise canceling feature, it does become second nature eventually.

There's a "touch/gestural" interface which could accidentally activate Bluetooth-only features, however I don't use the BT. By cupping the headphone I can also let sound come through temporarily, which I also had to learn not to do by accident.

As the headphones try to be context sensitive, the ambient mode may turn on automatically, such as when I sneeze loudly (or swear aloud). I guess the app would allow me to turn this automation entirely.

Yes, some of the features of can only be changed through an Android/Iphone app, which was initially annoying but it doesn't really need to be touched afterwards. There's an equalizer I've not really touched.

I made the Bluetooth pairing through the app initially, which was a mistake and I had to reset the headphones as this connection no longer worked. Then I made the BT pair properly through the phone settings, and only afterwards went to the app. After this there have been no problems connecting the phone to the app.

The convenient carry case has separate compartments for the headphones and cables.

I also had an opportunity to try this on an airplane while watching a film. Can't pretend I'm not hearing the airplane noise, but it's still quite effective.

I thought about comparing it to being in a car, but this would be misleading. The headphones not only cancels some of the noise but somehow "flattens" it. The difference is quite strong when I remove the headphones in a noisy environment such as the airplane. It's like returning to a three-dimensional world of sound.

The sound is good enough for my music tastes (electronic and some rock/pop). I'm not sure if Sony's reputation for headphones is the best ever. It could still be one of the better or even the best headphone I've had for general purpose listening, working just about as well with music, movies and games.

Hirttämättömät/Unhanged (2023)

It's nearly futile to write this in English, but in the tradition of this blog, here goes anyway.

*

After putting so much effort in watching, reading and even writing about Western films, and more recently, about Finnish western films, I could not avoid watching the first new theatrical Finnish western film since 50+ years: Hirttämättömät (The Unhanged)

Given that it's not strictly a film set in the West, one could argue The Last Border from 1993 was a western too. But unlike with the Last Border, here we see all the Western paraphernalia, such as wide-rimmed hats, revolvers, western outfits, horses etc. Together with the western-style music I'm going to say this is the more fully-formed Western of the two.

The new cast

The film in question is a remake of the 1971 "cult classic" Hirttämättömät ("Unhanged"). This was a sequel to the earlier fennowestern Speedy Gonzales - noin 7 veljeksen poika. (Speedy Gonzales: Son of About Seven Brothers). As most western clichés had been explored in the first film, the creators concentrated on a more narrow topic: three guys crossing a desert.

I actually have something of a soft spot for this small film, so perhaps count me in as one of the cult members. Speedy Gonzales fools Lonely Rider and Tonto to imprison him and to take him over to Threepencestad, "alive", so as not to have to take the trip himself. 

They circle around what is obviously a sand pit, and suitably for a pitifully small road movie, small episodes also take place. Mostly about who gets to drink water and who has to pull the cart. And who wins the heart of the women they inexplicably meet during their journey. It is funnier at the start, whereas it gets repetitive and boring at the end.

The 1971 original, with Vesku, Spede and Simo.

The original film was nearly entirely carried by the antics of Pertti "Spede" Pasanen, Vesa-Matti "Vesku" Loiri and Simo "Simo" Salminen. Mostly by Vesku, who had the broadest acting range of the three and the capability to fully embody the farcical character. Spede is his usual taciturn "Spede" character, derived from a more typical Eastwood-like western hero. Simo supplies much of the physical gags, who, as a non-native American, still plays one. (Gasp!)

For the Finnish kids who watched Spede-Show on TV in the 1980s, these three figures have became cemented as an epoch-defining comedic "trio", both by being genuinely amusing (in kid-metrics), but by also featuring in a spate of so-bad-they-are-good "Spede films" adults still enjoy for their campiness. Reviled by critics, loved by the masses, in this film we already see the trio dynamics in action: there are really very few additional characters.

This new version follows the structure of the original with some additions. Aku Hirviniemi tries very hard to out-bullshit Vesa-Matti Loiri's 1971 character but overstays what little welcome he had in the first place. Despite having a few amusing gags he ends up just demonstrating some kind of split personality and his needy and whiny mental collapses cease to be funny after the first time round.

The famous cart

The "Speedy" in this film is a young woman (Ona Huczkowski), who the other protagonists think is a boy. Ha ha. Spede Pasanen had such a screen presence many felt his face was amusing in itself, there's no such advantage to be had for this relatively unknown actor.

Andrei Alén, who also directs the film, plays the "Tonto" character. He might be relatively interesting as the non-Indian "Indian", but as Hirviniemi overflows every scene with his babbling, he and Speedy have very little room to operate.

Some new jokes are pursued from gender relations and environmentalist themes of our times, but perhaps fortunately the gender angle is not explored too far. No Indians are in sight in this film either.

I think the pacing of the film is at least okay, I felt some genuine curiosity about where this all might be headed towards. Not too much time is wasted on a single theme (a problem with the original) but unfortunately the comedy is just not that funny.

As for the additional inventions on display, at places it was hard to understand if a thing shown on screen was supposed to be a plot point in development, or just a (failed) joke in itself. I mean, some of the ideas are never developed further.

The black and white nature of the 1971 version helped it make look like a more authentic western. The new film has colors which brings some challenges for simulating a wild west appearance. All in all the film looks nice in a small way and for example the costumes are rather well made. 

Some digital background additions help the setting look more western-like, but at times they were jarring and I felt the point of the gravel pit aesthetics of the original has become lost.

What we see most of the time

The film has more nods to the Spede-films and Spede's type of humor than any real understanding of the history of Western films, which I would feel is a pre-requisite for a good Western comedy/parody.

The usual suspects are again referred to, Sergio Leone and Clint Eastwood films, with some Morricone nods in the music. From more recent films, we perhaps have some Tarantinoesque elements in how the film is occasionally framed as a nostalgic TV show with VHS quality ads.

Now that the native American aspect has been removed, there are very few "western jokes" left, and most of the comedy operates outside the western premise altogether.

Part of the comedy involves literal imitations of the 1971 trio—imitating Spede is practically a national pastime. Together with the cameo of Hannele Lauri (the "fourth" member of the trio), the film is in danger of becoming a meta-film about the emotional hole the trio left in the TV and film landscape for a generation of Finns. Some might say good riddance, but the existence of this film seems to indicate at least some people need to process that loss still yet.

Planet of the Apes

It's roughly 25 years since I've seen the earlier Planet of the Apes film series in full. It was handily available at Disney+ so I took the plunge again.

The creators could pull off five films in as many years, and despite piling on new science fiction ideas for each film, it's a surprisingly coherent trek.

The series famously relies on reveals, no further spoiler alert.

Planet of the Apes, 1968

A spaceship travels in the void, with four deep-sleep passengers. Already prior to the titles, Taylor (Charlton Heston) makes a huge point about how they might end up in the far future.

The ship lands on water, the clock says it's about year 4000, the passengers wake up and evacuate the craft before it sinks. Before this they confirm one of the astronauts is dead, a pretty blonde has turned into a hideous mummified corpse. My new pet theory is the woman died because Taylor smoked in the control room.

After landing, the film does some obfuscation so it wouldn't be blatantly obvious we are on Earth. Weird lightning strikes during daytime, ground is poisonous, there's very little or no vegetation, and they can't find a moon.

This sequence took more time than I remembered, and having the astronauts prancing around in the bleak landscape is visually interesting. Taylor speaks his mind a lot, and his attitude seems the worst of the trio. I wonder who was the psychiatrist who qualified him for the mission.

The astronauts find more livable areas with some primitive and mute humans, but alas, they are all hunted down by armed, clothed, horseback apes. Dodge dies, Taylor loses Landon and Taylor himself catches a throat-wound that renders him unable to speak.

Then it's off to Zira and Cornelius, the benevolent apes and Doctor Zaius of the science council. All speak... English. Taylor eventually reveals he is able to talk, at the most dramatic moment possible, but this doesn't much improve his position. Landon is found lobotomized, whereas Dodge's stuffed body is exhibited at the museum. 

This is both an inversion of human-animal relations in real world, but also a way to discuss civil rights and racial issues. All culminates in the farce of an ape tribunal. Taylor and Nova are exiled, they reach an expedition site together with Cornelius and Zira, with rumored artifacts about the planet's past. 

The film ends famously at the Statue of Liberty scene. But the cave already contains some clues the race preceding apes was human. A human doll says "ma-ma".

What apparently holds the ape society together is the firm belief in the superiority of the apes, something that could be undermined if the human past was revealed. And yes, in real world the discovery of evolution was (still is) a shock for many people.

The science-religious apes have a role in controlling what technologies are available. Zaius is well aware that flying machines would be possible, but presumably such devices would grant too much awareness. Apes have to be kept away from the Forbidden Zone, where the secrets lie.

The apes have fairly modern rifles and photography. ("Smile" is the first word heard from the apes) Otherwise the technology is not that advanced. Considering the pre-requisites for these two items alone, it makes me wonder why they have little else. 

Beneath the Planet of the Apes, 1970

I used to like all 1960s weirdness and camp a lot, so this was my favorite. Together with the nihilist plot, it felt hilarious all around. Now I see it's hardly comparable with the first film.

Another set of astronauts has landed in the future, the ship is wrecked and only one of them properly survives the crash. I'm thinking there's a permanent time-door in space that connects the two times together, rather than relativity and time dilation as such.

It seems the plot was written for Heston's character Taylor, but he was not available so we see only a few moments of him. Conveniently, Brent meets Nova from the first film and via visiting the ape colony and Cornelius and Zira and Doctor Zaius, and a needless escape detour, we go underground. 

Funnily, Zira thinks Brent is Taylor for a moment, because "humans look all the same". This is kind of revealing. After a visit to a New York subway station reveals to Brent it was Earth all along, damn you all to hell they finally did it, and for plot purposes he is now as good as Taylor and the story can continue.

The military-minded apes, led by Ursus the Gorilla, are intent on an expedition of conquest to the Forbidden Zone. For Zaius, this does not bode well but he accompanies the trek.

A small colony of mutated humans lives underground. They are able to discuss and instill pain through telepathy, and cast powerful illusions from afar. They pray for their god, a doomsday-tier atomic bomb from earlier days.

The campy elements are like some of the worse Star Trek episodes. The humans are costumed in a silly way. The sermon for the bomb takes too long. I admit the removal of the masks was and still is a little chilling.

The apes violently attack the human colony, and their mind power is no match for the "primitives". Taylor (Heston) is found from the prison and he gets some screen time. Nova dies, Brent dies, Taylor dies, Ursus dies, Zaius dies, everyone dies. The film ends up with a nuclear explosion that destroys the entire Earth, Taylor pushing the final trigger. Not sure why, he seemed rather anti-nuke in the first film.

This ending, trying to rival the first film, might look it could put a stopper to any potential sequels. But it didn't prevent three more films from appearing.

Beneath the Planet of the Apes was directed by Ted Post, whose better work includes Hang 'em High. It made me appreciate how these films might be a result of having an already existing infrastructure and know-how to make westerns: horse riding action scenes, guns, stunts, fist-fights, established film locations for arid desert scenes. The next film isn't a pseudo-western, though.

Escape from the Planet of the Apes, 1971

Some accounts have placed this film as the best of the series. Best of the sequels, might be more agreeable. It is still a film that only has existence under the armpit of the original.

Zira and Cornelius arrive to 1970s, together with Milo, a previously unseen genius ape, in a spaceship similar to what we've seen in the first two films. The whole scene with the expressions of the military personnel as the apes are revealed, is funny. It's not that incredible—the implication is they might be test pilots.

Milo dies in captivity, Zira spills the beans to the zoo vets: they are talking apes from the future.

It's not super-credible the three apes managed to get Taylor's timeship working. They also pretty much had to launch it just about Earth was about to go Boom, and "somehow" they arrived at the point of origin. 

Traveling forward in time in the first film was actually rather well within science. Going backwards is a bit suspect. With the magic time-door theory it could be conceivable.

The timing of the arrival is curious. Although the first film had some elements that suggested the astronauts did not originate that far from contemporary times (of 1968) it is still little weird the US had these super-ships in early 1970s.

Using contemporary times frees the film to explore comedy and human acting. Cornelius and Zira become public superstars, what ensues is a critique of celebrity-obsessed culture and some amusing scenes. 

Zira inadvertently reveals the Earth's inevitable destruction and that humans will be experimented on by apes. Acting the Herod, the politicians choose that whereas the pair could live sterilized, the offspring must die.

A switcheroo in a circus guarantees that the child-chimp Caesar lives, whereas Cornelius and Zira die in 1970s USA.

It might look like a clever idea: Apes didn't so much evolve during 2000 years, but the evolved apes came from the future and helped alter the genetic stock. In a way this makes things worse: Why would chimp DNA affect gorillas and orangutans? As the later films will show, the time travel did not create any new breed of apes.

Now it is explicitly discussed how the apes of the future came to learn English, an item that was usefully ignored in the first film.


Conquest of the Planet of the Apes, 1972

We begin with Armando (Ricardo Montalban) from the end of the last film, who has kept Caesar the talking ape hidden in his circus for 20 years. 

Yes, it is 1991, and as prophesied, all pets have died and humans took chimps as pets. It just that now they have been turned into slaves. Apes are imported from various countries and trained to work as servants, doing such important duties as cleaning windows, waiting tables, sweeping streets and shining shoes. 

I really enjoy the police state vibes in this small film, showing how the US political system has degraded. The society is apparently become dependent on the apes, yet as they have started to misbehave there is a bunch of black-clad cops and guards controlling them. Loudspeakers continuously announce ape incidents. It might be a little annoying trying enjoy your morning coffee at the streets.

The case of the talking apes must be very well remembered. Touring the city with Armando, Caesar manages to blurt out some words and the cops are fully committed to outing him. (Instead of disregarding it as an impossibility.) I'm wondering why the human society doesn't otherwise see they are fully headed for the Planet of the Apes scenario, which might be preventable by harsh actions.

Caesar has to flee, and in a roundabout way, he mixes with a bunch of newly imported apes and being so damn clever he ends up being the Governor's servant—the one looking for him!

Soon he forms a resistance, where activities and resources are redirected for the benefit of an ape revolution. As Armando is killed in a mind-probe related incident, Caesar becomes genuinely vengeful.

The film neatly interpolates the human world and what eventually becomes the Planet of the Apes. There are also little visual clues and technologies that suggest a path towards the mind control society in Beneath the Planet of the Apes. I'd even go so far as to say I like this better than the last installment, but maybe I am a sucker for theatrics and bleak architecture. It does go slightly downhill, though.

Apart from the friendly MacDonald, the government appears to be fascist: "Torture? But we don't do that to humans?" Having basically "good guys" do these kind of decisions made Escape more nuanced. As Caesar grows more capable, he becomes more ruthless. It looks in the end there are very few heroes to root for.

The fighting in the end takes too long. Yes, it shows the first "netting" of humans by the apes. We get the point already. 

Much as with the previous film, part of me is concerned with the timeline. The Planet of the Apes was 2000 years in the future. It now looks like key events leading to it actually happen in the few decades after Taylor's ship left. In fact, if Taylor had missed his ride he might have seen the rise of the apes first hand, no need to visit the year 4000.

This does make the events more relatable, though. The mistake in Beneath... was to show a human society too far removed from what we know.

We're now shown that apes were made clever through breeding and training, without the Cornelius+Zira genetic contribution. Importantly, we're shown Caesar's example inspires one of the most clever apes to say a single word.

Battle for the Planet of the Apes, 1973

The film begins around about 2600, with a wise old ape recollecting things from the ancient past. Then it's off to early 2000s.

Again, some decades have passed, it's unclear how many. Caesar and his wife are around, and so is Aldo the gorilla. The brother of MacDonald from the last film is around (In absence of MacDonald's actor I suppose) and the events of Conquest of the Planet of the Apes are still in living memory.

But, a lot has happened. The nuclear holocaust, for instance. Much of Earth is now a radioactive wasteland, and although the remaining apes and humans have found a livable oasis, many humans also live under the nuke-melted city of New York.

Strikingly, the society is already quite close to what we saw in the first film, apes have their caste system and although humans still speak it looks they are second-class citizens here. Aldo the gorilla is the most militant of the lot, jealous of the more clever apes and the most clever leader Caesar.

Caesar becomes intrigued by the prospect of finding tapes of his parents in that city and answers to questions. So he, McDonald's-brother, and the wise orangutan Virgil do an excursion. They find the tapes and the fact Earth is destined to be destroyed in around 4000. Virgil muses that the future might not be fixed and that they could choose one "highway" from another. 

The mutant city is a dangerous place, as the society there is developing towards the bomb worshiping mind-controllers of year 4000. Unable to catch the intruders, the mutants nevertheless learn of the existence of an ape colony, and in a weird act of retribution their leader wants to destroy the apetown. 

The most interesting part of this 1973 film is how it precedes the Mad Max series, or perhaps its lesser imitators in the 1980s. The humans wear silly grey-black uniforms, drive crusty motorcycles, cars, jeeps and a school bus through the desert. The drab society in the dark underground city reminds me of the later Escape from New York. These are minor themes here, though.

The gorillas see their moment, Aldo takes control of the colony, breaks into the weapons storage, corrals all the friendly humans and sets out to destroy the opposing force.

The battle is not that impressive. Caesar plots to win the fight as non-violently as possible, but the gorilla force kills the fleeing mutants. The gorilla plot and culpability of Aldo in ape-murder ("Ape shall not kill ape") is revealed, Aldo dies and the humans are set free. But how free, ask the humans. Does the spiral of violence never end?

The bookend closes and the wise ape from 2600s is shown to be teaching a class of both human and ape children. I guess it might indicate the future took another route, and they all learned to live together. But as it's still far from year 4000 and so much could happen in a few decades, it's ambiguous.

As a film, this last installment is quite weak. As an addition to the Planet of the Apes lore, the story is reasonable and fills in an interesting period in the human-ape relations. The time scale becomes even more silly, as the future ape society is now nearly fully formed after 40-50 years from since Taylor left. His ship is probably about 2.5% of completing the distance to the Planet of the Apes. Bon Voyage, Taylor.

Voxicon keyboard

Apparently I just can't resist buying a new keyboard once in a while.

At least this one fills a different niche than usually. The Voxicon DK-199B-G is a tiny foldable Bluetooth keyboard.

Previously, my on-the-go keyboard has been a battery powered Apple Mini keyboard. Although it feels fine, I was looking for something even more portable. Also, as a battery hog it was necessary to remove the batteries when not in use.

Well, less about the Mini and more about the Voxicon. Three Bluetooth channels, dozens of hours of battery life promised. The charging is done with the included Micro-USB cable, which is getting a little old-fashioned.

Folded, the dimensions are 202mm x 47mm x 16mm. A magnet keeps it together. It's almost conceivable the keyboard could be carried in an inside breast pocket.

Opened, the keyboard is 202mm x 90mm x 15mm, depending on whether the screen stand is folded out. The separate parts of the keyboard are connected with a ribbon cable, I can only hope it is sturdy enough.

I first tried typing with Google Docs and a version of Sublime Text on Android. The experience on overall was passable.

The keys itself have a quite good, crisp, tactile feel to them, not the usual cheap BT/IR keyboard mushiness.

The smooth bottom means a cloth or rubbery surface could be desirable.

There's a little bit of rise to the keys, too, something often forgotten from even larger mini keyboards.

I have to admit my hands are somewhat too large for this, but the final verdict will have to wait as I haven't written that much with it yet.

There are the usual woes of a compromised keyboard, many common symbols are in different places.  Although backspace is technically in the correct place, it's at a cramped corner and not above the Enter key, because of the Enter shape. 

The design is such that the stand "flaps" should be opened to give more room for fingers at the top row. The flaps are removable, though, with what looks like three very tiny Torx screws. But I'm not going to mutilate this keyboard yet.

Some common symbols might need more key presses than usual. Home/End/Page Up and Page Down are reasonably accessible from fn+cursor keys, and Scandinavian keys are at least direct keys even if a little weirdly placed.

As mentioned, the keyboard includes a stand for phone/tablet, and it is simple to use. For added coolness factor I prefer to have a separate stand for the phone. The separate stand is more pleasant to use with a tiny screen as it can be positioned better.

The built-in stand might make more sense with a tablet, to give that pseudo-laptop feel and your gaze can be a little higher.

For the occasional urge to make notes or an e-mail on a phone, I can justify this better than the Apple Mini keyboard. Certainly the Mini is better for typing, but this micro-keyboard has some advantages and I'll try carrying this around instead. It's light years better than the atrocity I once covered in my blog.

Edit 19.8.2024: Press FN+BT selection key (1-3) long to enter the pairing mode. The light will start flashing.

Chess cheatsheet?

I have been playing online chess on and off for a few years now, with the occasional over-the-board game thrown in.

At the beginning, I tried to collect material for a potential "chess cheatsheet" or memory aid. The resulting text has many layers from different times. Some of this seems silly now but I'll make it online anyway. 

I've not kept a good track of where I have picked up a particular advice. I have read books from Gideon Ståhlberg, Fred Reinfeld's The Complete Chess Player, and a few glances at Max Euwe and Keres & Kotov and other books. Plus whatever I found on the internet at that time.

More recent theory I found from Ristoja & Ristoja's chess books from the 1980s and I've had a brief look at 2000s theory from Mika Karttunen. Turns out many things that were still considered iron rules in 1960s books are already in the 1980s considered far less imperative: a chess position is now considered as a dynamic situation.

Apart from what I may have read as a kid, my recent starting point for chess theory was not from a chess book. Instead it came from Dreyfus and Dreyfus' book Mind over machine: The power of human intuition and expertise in the era of the computer from 1986, a critique of artificial intelligence which uses chess as one of the examples. 

The skill model is somewhat suspect but it is great food for thought. Briefly put, the authors identified skill "levels". Whereas beginners cling to formal rules, masters of a skill are often unable to explain their skill and their moves. A chess master accesses the repertoire of knowledge almost as people would recognize faces.

I initially made the wrong conclusion from this skill model: that to become good you just "wing it" and play "intuitively".

On the contrary, the takeaway should have been that I'm a beginner and there's nothing wrong about looking for rules and principles first, and then eventually integrating this to a more daring, intuitive play. Eat the humble pie.

Still, I've liked the idea that theory can be the end result rather than a starting point. This is another simplification, but often what you find in books is a summation gained from a long career, an insight that resulted from a huge amount of playing and perhaps teaching chess. The road to this expertise is often forgotten, and hence we still have books that first show how the horsie moves and then goes straight into the subtleties of a variation of a Sicilian opening.

Put differently: it's often that a theory is helpful only after you have some grasp of the problem area for yourself. For example, instead of trying to memorize an opening, let the openings "come to you" through playing huge amounts of games and then take a look at how a common opening might be played.

After the initial rush to books, playing a lot of puzzles and gaining playing hours were the most important thing for improving. Chess skill advances as any skill does, a combination of playing a lot, doing exercises and acquiring some "theory" and perhaps some goal-setting suitable for one's skill level.

"Exercises" might mean playing huge amounts of puzzles or concentrating on some particular opening or game style, or attempt at an analysis. Also, fast games might be exercises for slower games, and vice versa.

Simplest theory are absolute things like possible endgame checkmates. Despite being "simple" there's a lot of this and it can be hard to remember on the spot or under time pressure.

Openings are also quite well understood and measured, but again this doesn't mean that knowing a bunch of opening moves will help a new player much. More about this later.

The middlegame is the ground for the most vaguest theory. There are just too many potential situations and patterns to be identified and addressed to make into iron rules.

Well, anyway, here's the stuff:


Piece movement (very early notes)

Pieces can be visualized as both the piece and the area it threatens. Rooks and Bishops form perpendicular and diagonal crosses. A Queen forms both.

In addition to the 8 directions, it may help to see the Queen as carrying a star-shaped zone. This is useful when forming certain types of checkmates.

Furthermore, the pieces can be thought to "paint" the threat areas they can reach through one move, creating a sort of secondary zone of motion/threat.

This way it would be already possible to see moves ahead without having to logically examine the repercussions of every possible move as in a decision tree.

This is more like an at-a-glance assessment of the zones threatened or defended by your or your opponent's pieces.

The knight is not really a special case, but it certainly feels like it is. This may be because it requires a little more complex visualization than above.

For example, finding safe space around the knight:

The above shows the squares the knight could threaten after 1 move (circled squares). I felt like highlighting the "more safe" squares: these are squares the knight can't threaten even in 2 moves. (There's one more, in the corner where the black king is)

It's easy remember that putting pieces next to the knight makes them safe from it, this alone can be helpful in a fast endgame where forks need to be avoided.

Instead of the one-step, two-step motion, or "L shape", the knight may be better visualized as series of 2,1 or 1,2 "vectors".

Other pieces may be visualized with the knight zone around them, to help assess how to reach that piece (often avoiding a fork).  "Safe" locations are at (2,2), (3,2) and (3,0) relative to the knight, and these are also quite easy to visualize as a box.

Just as an example, analyzing some of the "Knight laws". A lot of this is re-stating the same thing in different ways.

• The knight always threatens squares of other colors than the square it is in.
• Pieces on different colored squares cannot be directly forked by the knight.
• If the knight moves, it will never threaten any of the same squares as previously.
• If the knight moves, it will threaten the square it was in.
• The knight takes 2 moves to threaten a directly adjacent square (not diagonally adjacent)
• After moving the knight, a square it might threaten, can often (but not always) be threatened from an alternative square .
• The knight threatens less squares from edge/corner, and is more susceptible to imprisonment there. Still, good ideas based on a knight at the edge ought not be dismissed.

Conversely:

• To avoid being threatened by a knight, a piece can be positioned next to it.
• Other easy to visualize safe spots are ±2,2 ±3,2 and ±3,0 locations relative to the knight.
• Be mindful of positioning pieces in ±0,2 ±2,0 ±0,4 ±4,0 relation to the knight.
• To avoid getting forked, pieces may be put to different-colored squares.
• A bishop can quite effectively limit knight motion from the ±3,0 and ±0,3

Would it be nice if all these thoughts could be integrated in visualizing a knight, obviously the checklist is too long to to go through consciously every time you look at a piece.

And it can still get tough to avoid those damn knight forks.

Another idea I've toyed with is that pieces like the Bishops and Knights exist in another "space" within the board.

Looking the chessboard naively, it is a horizontal-vertical "rook-space", but for the Knight it opens up differently:

A slice of knight's "space" within the board.

Another slice of Knight's "space" within the board.

Later note: There's not much support for this kind of visualization in any of the books I've read, and I'm unsure about it myself. I felt it was interesting at the start, but truth be told much of this thinking isn't active during the games. It more likely develops through playing a huge amount of games and puzzles.

Openings:

There was a phase when I tried to learn some interesting-sounding openings by heart, but it turned out to be not too helpful. Again, I now think it is better to remember openings through playing a lot of games while sticking to as few openings as possible.

But, even if I always wanted to play e4 with the intent of playing Spanish/Ruy Lopez, there are various reasons why I am not allowed do that. Obviously I might be playing black and the opponent begins with d4.

But even when playing white, I could come against a number of openings, such as Sicilian, French, etc. This means that learning at least something about bunch of openings is needed. An alternative might be to stick to a less volatile opening such as the London system, but even then you can't choose to play it as black.

2023 note: I stick to e4 with white, and study the more likely openings that result from this choice. Black responses to different white openings need to be studied also.

At Lichess low level online blitz games, I soon started to recognize Italian Game and the Parham Attack and the blatant traps inherent in them. After this it becomes a good idea to find out the good moves for responding to these routine threats and building up a better defense.

I've come across an idea that beginners do not benefit from knowing named openings all that much. Any advantage gained from a correctly memorized but poorly understood opening may melt easily after a few moves anyway. Knowing that Sicilian is the best black response at master level, might lead to a poor play for the beginner player.

Perhaps knowing the openings is initially more about understanding what the opponent is trying to do, and what traps might be around the corner.

Development, simplified, is to move the pieces out of the king's row. (Pieces=not pawns) Development can be considered complete when bishops and knights are out and castling has been performed.

Instead of learning openings by rote, rules of thumb may be useful for improving the opening:

From Reinfeld:

Primary idea:

• Create viable attack positions through acquiring control over center
• Ensure defense and protection of all forward-moving pieces

Alternatively,

• Refrain from defining the pawn lines too early
• Refrain from castling too early

This is an approach that enables you to change your plan later as a reaction to the opponent's moves. I've felt these are rather abstract ideas for the beginner, though.

Pitfalls:

• Immediate holes in defense
• Inconsistent approach (?)
• Too much time spent in achieving a specific tactical idea (=lost tempo)

Notes from Nimzowitsch's ideas about opening for beginners (which is not the same as his system):

• Develop "All", ideally by moving pieces (non-pawns) only once.
• Pawn moves are not development, ideally only 1-2 pawn moves in an opening.
• Pawnless advance does not work either
• Formula: Developed Pieces = Tempo.
• Compound moves. Moves that both develop and force opponents to waste moves. ("Don't just develop, develop and threat!")
• In a closed game (d-game) the development may be slower and with more pawn movements.
• Flank pawns are a waste of time in an open game (e-game) 
• Never play to win pawns when development is unfinished (exceptions...)
• Center pawn should always be taken if not too dangerous.
• Exchanges and gain of tempo, these are related.
• It is a mistake to move a piece several times to exchange it for a non-moved piece.
• Liquidation = "radical" exchanges that relieve tension in the center (if necessary).

Again, I can hardly say I've internalized much of this.

Some other ideas to observe during the opening:

• Don't move the queen early on unless it's really called for (traps, regaining a pawn)
• Be wary of moving the f-pawn at the very beginning (not often compatible with kingside castling, may also block the knight)
• Knights before bishops, but also be wary of blocking your bishops.
• Observe the potential threat from bishop to h2 (h7) pawn and devise the castling accordingly.
• Likewise, see if the Greek Gift can be realized against the enemy King-side fort.
• Possibilities for variations of the Fried Liver attack or other types of knight/bishop double attacks, but it's almost never worth it to lose both just to gain a rook and a pawn.
• 2023: I almost never look into "Fried Liver"
• Possibility of removing opponent castling through queen exchange
• However, without queens the castling is not that meaningful
• Preventing or postponing the opponent from castling

Some of these are flexible depending on the situation. Otherwise the opening would become too predictable. Reinfeld says that some quirkiness can be helpful. Possibly, two players playing an opening "correctly" are really doing a disservice to each other.

Especially older books sometimes suggest playing a lot of e4-games before moving to d4 games. Not sure why, but to me it's seemed that a Ruy Lopez, although very deep, results in a more "normal" chess than other openings.

The "control of the center" seems like an obvious idea but at least to me it is a difficult concept to grasp. It's easy enough to observe the opening pawn exchanges and the building tension around them, and it is clearly a bid to control the center. But what is to control the center? Having a bunch of your own pieces cluttering the center and blocking the diagonals is often not that helpful.

But I've seen that if the opponent has a well protected pawn or two at the center, and you don't, this often spells disaster. Similarly, if the center is empty, a vicious bishop-pair can decide the game. 

Middlegame:

I have little to say about middlegame. Tactics still seem to dominate this area, together with spotting opportunities, either plain unprotected material, weakly positioned pieces or overburdened defense. These are what Reinfeld calls "landmarks", a motive for planning forward. 

Steinitz said: The player with the advantage, MUST attack when the opportunity comes, it is an imperative. Attack towards the weakest side, the weakest position.

Current theory sees that these kind of "iron rules" are never too absolute. They might be considered as material for learning and reflection. (The advantage may be other than simply material.)

Keres & Kotov felt games can be characterized by castling-sides but also the openness or closedness of the center. This would give, roughly, a matrix of 12 "game variants" if non-castling is considered. Other literature has simply suggested a division between open and closed games.

True or not, there are definite ideas related opposite side castling. A pawn advance can be attempted on the opponent's kingside, as Keres & Kotov suggest. "Who has the initiative, wins!" Pieces in the way of advance can be threatened. A fianchetto/g pawn can become a weakness in the kingside. The defender should beware of moving pawns at the side under attack.

Later note: The pawn advance isn't an end in itself, the point is to open a line on the opponent's castled side.

Bishop/knight exchanges should not be done without reason. Is the board more advantageous for bishop or knight play? (Your's or opponent's) What happens to the opponent pawn structure as a result of the exchange? Seemingly innocent exchange might result in an open line for a rook.

At one point, playing an enormous amount of puzzles improved my middlegame tactics quite a lot. Recently, playing "puzzle storm" at Lichess was also helpful at activating the eyes and the brain to recognize opportunities and what to do with them.

2023: Puzzles helped greatly in recognizing tactical opportunities, but they don't help much in creating the opportunities in the first place.

"Planning" largely comes into play here, but this is still a grey area to me.

Tactics

Tactical moves: Euwe says tactics is the point where you really need to plan moves "ahead" and consider alternatives. In this light Chess is not constantly about envisioning very long decision trees, but only when needed. Perhaps one reason for opening theory is not to burden the brain too much at that point of game.

Positional play: "when there are no tactics to play"

Put more pressure on already threatened squares. Are there subtle ways to improve rank and position? Defend undefended pieces or increase the defense of weakly defended squares.

Prepare for lines to open. Rooks are placed to an open line, or to defend a passed pawn. Look for possibilities to place rooks on the "7th row absolute". (No moves should not be made in isolation of what the opponent is doing.)

Pawn structure becomes especially important in the endgame. Envision the endgame pawn situation already in the middlegame.

Euwe suggests (and I'm expanding what is really a side note in the text) that Chess is about translating advantages to others. No one player can have all advantages at the same time, but only some for some of the time. These may need translating into what the situation requires.

Some examples of advantages Euwe mentions: Material, Rank, Mobility, Spatial advantage, Sustained pawn formation, Safe position for the king, Tempo, Initiative of attack, Knight on a strong square, Bishop pair...

Exaggerating Euwe's ideas, the situation in a Chess game might be seen like this:

These are just examples of opportunities of exchanging one thing for another. Sometimes, in beginner games a really fast attack might bring rewards, but when it fails, it often marks a turning point and the attacker loses. Almost everything else was exchanged in order to make that one attack possible. 

Leaving out defense and castling may help create an impressive-looking attack, but unless it is motivated by a provable future advantage or victory, it shouldn't be done.

Others that come to mind are Rook controlling the "7th row absolute", disadvantages might be "bad bishop" or overall "bad squares". Loose pieces, loose pawns, overburdened defense etc. should be interpreted more as Fred Reinfeld's "landmarks" or as disadvantages.

Controlled center and a bishop pair is apparently a good combination. A bishop pair without the center may not be such a superior strategic advantage. Be mindful of especially queen/bishops positioning directing towards/through center.

Of course, overall material value of pieces is still a good indicator of your standing, but an immobile piece is a non-piece at that point of time. Other issues can subtly undermine your pieces' apparent material value. 

The most concrete idea that results from this reading is the function of sacrificing a piece. Although the best goal is a certain checkmate, a sacrifice could have the following immediate (multiple) effects:

• Forcing desirable opponent moves
• Breaking the opponent's pawn line (and/or creating double pawns)
• Opening a beneficial line, rank or diagonal for yourself
• Creating disadvantageous squares (color, or otherwise)
• Removing a blockade whereas creating one for the opponent
• Removing opponent's bishop pair
• Preventing opponent from castling
• Breaking the castling

Euwe also makes the important point that the advantage is often temporary, and can become lost very quickly. Consider again a sacrifice that leads to a position that looks like it could lead to a checkmate, but does not. The sacrifice was for nothing. Of course, a 100% certain path towards a checkmate obviously justifies any kind of sacrifice or loss of other advantages.

To summarize, a sacrifice is not only made just to be able to win a more valuable enemy piece a few moves ahead, but different advantages can be "bought" or "borrowed" with it.

Vice versa, be very doubtful of something that looks like an offered piece.

For the beginner the problem is to recognize these advantages in the first place. So, for a long time I suppose the material advantage remains the most identifiable.

Later reflection: This Euwe idea made originally a big impression on me, as if some revelation about Chess had been opened up. I now have to accept it hasn't made a huge impact on how I play. Perhaps the biggest takeaway is that although good advice and rules exist for strategically and tactically sound game, at a given moment "you can't do everything". You often have to disregard some aspect in order to gain initiative or tempo, and pay the price later. If you don't, your opponent might.

2023: Recognizing other advantages than material, is more important at first. The "insight" that these can be exchanged or sacrificed to gain others, isn't that useful without this cognition. And it would be nice to find moves that "do everything" or at least many things at once.

Thoughts on "strategy"

Most initial learning seems to concern tactics. I can't say I understand strategy much as yet.

I come again back to Mind over Machine.

"While [computers] are perfect tacticians [...] computers lack any sense of chess strategy. Fairly good players who understand that fact can direct the game into long-range strategic channels [...]" (Dreyfus and Dreyfus, 1986, 113.)

This, at a time when computers were not especially good at chess. E.g. if a computer has a horizon of 4 moves ahead, it might miss a simple idea about promoting a pawn that even a beginner could see. The point is that strategy obviously is something that goes beyond the scope of the next few moves.

The chess literature isn't always that clear what kind of thinking belongs to strategy. To some, topics such as weak/strong squares and pawn structure is already a strategy topic rather than tactics. "Improving position in piecemeal fashion" would then be strategy.

Discussions on pawn structure are difficult to follow, and admittedly boring compared to tactics. As a basic rule, consistent chains are better than pawn lines with holes. In the past, doubled pawns were considered undesirable, but chess theory nowadays sees them as potentially weak or strong depending on the situation.

As a beginner, I easily disregarded pawns. Promotion was something of a happy accident rather than a design. This also meant if my opening resulted in a loss of few pawns, I was okay with it. Now I am paying more attention to pawns and I also see a lot of the openings build-up around pawns and threatening and defending them. Later in the game, planning might be based on simply eroding the opponent's pawns before endgame.

This just to show that the player learns to see more than what is immediately apparent on the board, so eventually the player perhaps begins to recognize strategic patterns rather than just positions with opportunities. Literature might discuss "latent energy" or "tension", where I can see nothing but the board and the pieces.

"Strategic choice should be ideally non-obvious to the other player."

More recent theory does not recommend having one major plan, but shift it according to how the game develops, dynamically. To me this makes the notion of a "plan" strange, but clearly it's not a healthy sign if you find yourself moving pieces aimlessly.

"I could checkmate only if this and that piece was here and if this and that opponent piece was removed" seems to me like an indicator of a premature checkmate plan. Instead, improve position and look for the opportunity to improve the checkmate idea or develop another one.

2023: Seeing a germ of a plan in this way, is actually a positive thing. Just try to find out what needs to be done.

Again I'm reminded of Fred Reinfeld's "landmarks", which experienced chess players learn to see at a glance:

• Loose pieces suggest forks.
• Loose pawns are a weak spot.
• Overburdened defense is a weakness.

If the opponent's castle is very strong it may not make sense to have a direct checkmate plan at all. Instead erode the enemy pieces and ensure there are pawns for promotion in the endgame or a clear superiority of material. Pawns at the non-castling side are an advantage. "This is a war of attrition."

Ståhlberg: In master-level play, the one who loses a pawn with no gained advantage, will lose the game.

Ristoja: (paraphrasing only slightly): Only the beginner aims to checkmate. The mature chess player plays the opening to have a good middlegame, then plays the middlegame to have a good endgame. The threat of a mate is often a more important tool than a premature attempt to win.

Reinfeld also says: the player who is ahead materially, seeks to exchange Queens, to simplify the game. The one who is behind, relies on creating confusion, traps and complications.

Karttunen: (again, paraphrasing) After exchanging queens, the castles are not quite as meaningful. The kings might even be better at the center after the exchange has happened. The player whose castle is broken or about to be broken, might want to seek to exchange queens, despite everything else.

(Exchange of queens may be more desirable for the one who has the king in the center, as removing the queen reduces the checkmate options for the centered king.)


Endgame:

The endgame with very few pieces becomes again a terrain for more discrete knowledge, such as whether and how to checkmates with certain combinations of pieces. 

I will not list checkmate patterns and piece combinations for the endgame, however they simply need to be known as the more sophisticated games are usually decided here. When the clock is running out, it would be better to have a good grasp of how to checkmate quickly with a queen or a rook without stalemating.

The term opposition should become familiar when dissecting pawn endings.

This advice is more about the point of transition from mid-game to endgame:

• Pawns, preferably on non-castled side are useful (already the threat of promotion is a powerful tool)
• Two bishops are often more valuable than two knights or knight+bishop
• Two rooks can be more valuable than a queen
• Queen endgame: one pawn advantage is not enough. A strong, free pawn is needed.
• Visualize the pawn square rule for promotion

Random notes

"When threatened, find the best way to do nothing"

If the castle seems to hold, why alter it? Use the tempo to develop an attack instead.

The most important rule is... "YOU BELONG HERE!"