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Home Computing Pioneer Sir Clive Sinclair Dies Aged 81 (theguardian.com) 103

LoTonah writes: Sir Clive Sinclair, the man behind the Sinclair Spectrum and the first computer to retail for under a hundred dollars (the Sinclair ZX-81, A.K.A. The Timex/Sinclair 1000), died September 15 after battling a long illness. His daughter, Belinda, said he died at home in London on Thursday morning after a long illness.

Sinclair invented the pocket calculator but was best known for popularising the home computer, bringing it to British high-street stores at relatively affordable prices. Many modern-day titans of the games industry got their start on one of his ZX models. For a certain generation of gamer, the computer of choice was either the ZX Spectrum 48K or its rival, the Commodore 64. Belinda Sinclair, 57, told the Guardian: "He was a rather amazing person. Of course, he was so clever and he was always interested in everything. My daughter and her husband are engineers so he'd be chatting engineering with them." He left school at 17 and worked for four years as a technical journalist to raise funds to found Sinclair Radionics.

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Home Computing Pioneer Sir Clive Sinclair Dies Aged 81

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  • by neilo_1701D ( 2765337 ) on Thursday September 16, 2021 @05:31PM (#61802677)

    The ZX-81 changed the course of my life. It introduced me to programming, and was the computer my parents could afford to buy while I was in high school. Without that black wedge of unreliable electronics and awful TV output, I don't think I'd be where I am now.

    Thank you, Sir Clive, for all that you did.

    • by AmiMoJo ( 196126 ) on Thursday September 16, 2021 @05:56PM (#61802743) Homepage Journal

      That was a moment of genius by Clive. He didn't do any market research, just thought it would sell and went ahead and ordered 100k units to get the volume pricing. Launched at under £100 and it sold 1.5 million units, a quite staggering number considering it was a new product that the man in the street barely understood.

    • by lazarus ( 2879 ) on Thursday September 16, 2021 @06:06PM (#61802767) Journal

      Mine too. I purchased my ZX-81 while I was in highschool as a bag of electronics that needed to be assembled and it was my first computer (with a grand total of 1k of memory). It was an affordable way to get into the very new home computer hobby. I worked an entire summer to be able to afford it.

      But the very best part of the whole package was the manual. An extremely well written and useful introduction to programming.

      RIP Sir Sinclair.

    • Same here. I had to soldier it together myself. I had to deal with a dodgy external RAM pack that I created wooden stabilizers for, and eventually hacked a real keyboard on top of it... it was the system that I learned programming on, and I've aways been happy I started there.

    • by ljw1004 ( 764174 )

      The ZX-81 changed the course of my life. It introduced me to programming, and was the computer my parents could afford to buy while I was in high school. Without that black wedge of unreliable electronics and awful TV output, I don't think I'd be where I am now. Thank you, Sir Clive, for all that you did.

      Same here. I loved borrowing code books from the public library, typing them in with ZX-Spectrum Basic, and playing them. At age 8 when most kids don't have a clue what they want to be, I was already certain I'd work with computers. 25 years later I got a job as language design lead for Microsoft Visual Basic. Genius, Sir Clive.

    • Re: (Score:3, Interesting)

      by Tablizer ( 95088 )

      For Xmas I got the Timex Sinclair 1000, the 81's brother. I knew BASIC from an after-school program and was super eager to try it out at home. I typed in '10 PRINT "HI MOM!"...20 GOTO 10" and pressed "run" and awaited the magic...

      I got a syntax error; something like "P is not a recognized command". I stared at the screen for 5 minutes, unplugged it, keyed it in again, pressed "run", and still got a syntax error.

      I was getting flustered and started yelling. The box had pictures of BASIC on screens, so it was

      • by Tablizer ( 95088 )

        Correction, should be: I typed in '10 PRINT "HI MOM!"...20 GOTO 10' and pressed "run". Actually it's like this:

        10 PRINT "HI MOM!"
        20 GOTO 10

        • Except.... (Score:4, Interesting)

          by Sebby ( 238625 ) on Thursday September 16, 2021 @08:45PM (#61803113)

          Correction, should be: I typed in '10 PRINT "HI MOM!"...20 GOTO 10' and pressed "run". Actually it's like this:

          10 PRINT "HI MOM!" 20 GOTO 10

          Except there was no "!" in the ZX81's character set! :) The best you could do was a "/" with a strategically placed period on the next line.

          • by Tablizer ( 95088 )

            As far as displaying it, couldn't one use CHR$(33)?

            • by Sebby ( 238625 )

              As far as displaying it, couldn't one use CHR$(33)?

              That's the thing - Sinclair computers (the earlier ones, like the ZX80/81, Spectrum, etc.) didn't have the "standard" ASCII set (I don't think it had really become a "globally recognized standard" by that time), so they had their own character set, which didn't necessarily include everything we now assume in a set, like '@' and '!' and others, and often had their own "non-standard" codes - so for example CHR$(0) actually represented a space character on the ZX81.

              • by Tablizer ( 95088 )

                Hmm, seems they wanted a mellow user base. I mostly used it for games and graphical toys, so didn't notice character oddities.

      • I saw the command verbs before on the keyboard, but thought they were merely a shortcut for people who didn't want to type. However, they were not a shortcut, they were the ONLY way to enter a command.

        Entering the basic commands this way meant that the BASIC interpreter did not requre a tokeniser. The tokens were entered directly and just displayed as text. I suspect that this saved a whole lot of ROM space and possibly made a speed difference.

        • by kenh ( 9056 )

          The tokens were entered directly and just displayed as text. I suspect that this saved a whole lot of ROM space and possibly made a speed difference.

          Not sure how much space it could have saved - MS tokenized basic even in it's 4K interpreter, and the tokenization occurred after you hit "enter" and before the interpreter presented you with the cursor for the next line/command.

          I wonder how much money was saved by eschewing MS ROM BASIC and instead writing your own? I wonder what the per-unit license fee was at the time for MS 4K or 8K BASIC?

          • >I wonder how much money was saved by eschewing MS ROM BASIC and instead writing your own? I wonder what the per-unit license fee was at the time for MS 4K or 8K BASIC?

            It doesn't really matter. If it saved half a femto penny, Clive would have gone for it. Sinclair's design philosophy was all about extreme cost saving. I used to work with engineers who worked at Sinclair during the ZX8[1,0] days and they had plenty of stories.

          • Not sure how much space it could have saved - MS tokenized basic even in it's 4K interpreter, and the tokenization occurred after you hit "enter" and before the interpreter presented you with the cursor for the next line/command.

            You’re right - the tokeniser is much smaller than I would have thought. I counted 106 bytes of machine code in the 4K basic you mention.
            [Disassembled here ] [altairbasic.org]Though with only 1k RAM and 4k ROM that’s about 2.5% of your code storage so I wouldn’t put it past Sinclair to try and optimise the code that way. I wonder how it compared to the size of the keyboard code needed to vary output with context? Or did they just make the token and the character have the same value?

            • by Tablizer ( 95088 )

              What about if they just parsed on the 1st two letters of the command and ignore the rest? The lookup table of 2-letters-to-command# would be pretty small. (There may be a handful of overlaps, but that shouldn't take much code to handle.)

              • I wasn’t counting the size of the lookup table in the tokeniser size, as it has to exist to decode the tokens for display on screen anyway. Yes, there are ways of compressing the token to keyword table, which also speed up parsing, for example by storing a lookup tree or a representation of the finite states for the parse tree with the token at the end. Stopping after the first unique letter would certainly work for parsing. But two way lookup is needed, and in any case both the Microsoft Altair b

      • by AmiMoJo ( 196126 )

        By that time the people working for Clive had got very good at squeezing the most out of tiny ROMs, because he was always demanding cost reductions on memory.

        The fact that you couldn't just type PRINT character by character, but instead had to press one single key, meant that Sinclair BASIC didn't need a tokenizer. The P key entered the token for PRINT directly, and only the de-tokenizer part was needed to display a listing. It also saved some RAM.

    • by sg_oneill ( 159032 ) on Thursday September 16, 2021 @09:38PM (#61803201)

      Yeah. I actually had an Amstrad, but much of the design of that thing was in response to Sir Clive's Spectrum, and the software available on Amstrads had a tendency of being ports from the Spectrum (although often poor ports that tended to ignore the higher capability of the more expensive Amstrads)

      Sir Clive was a strange dude. He really wanted to kick start the electric car and electric bike thing, but he was just too far ahead of his time, and perhaps a little too eccentric to design a model that the market would accept.

      Vale. One of the true pioneers of the home computing evolution. Arguably the UKs Steve Jobs.

      • He set back the idea of EVs by at least a decade by making them laughing stock. For years afterwards, if you mentioned EVs people immediately visualised Sinclair's C5 crap. It seemed to be an axiom that EVs had to be tiny, ugly, slow, and quirky.

        For millenials, the C5 was an open 3-wheeled 15 mph (max) plastic tub that you needed to pedal (electric assisted) most of the time. All and any of those atributes condemned it. I remember the press launch on TV and I took it to be a spoof. I, like most people,
    • The ZX Spectrum did the same for me. First the 16k version which was amazing in itself but man, when I managed to save up enough to upgrade the memory to 48k a whole new world opened up. It's still there in my old room in my parents house.
    • It was a Sinclair computer that changed my life too. It was the new ZX Spectrum though in the early to mid 1980s.

      Although I had graduated and got licensed as a pharmacist, the retail pharmacist as a job never clicked with me. Too much human interaction. Very boring. Unchallenging. Totally different from studying pharmacology, pharmaceutics, chemistry, and so on ...

      Computers opened up a whole career for me, and I never looked back, doing everything from software development, support, systems administration,

    • by WLattery ( 62219 )
      Agreed....ZX-81 was my first computer as well, and got me into the programmer, and later IT architect career that I have today...
  • He did not invent the pocket calculator, as even a cursory glance at Wikipedia will tell you. No individual did that on their own.
    • by AmiMoJo ( 196126 )

      True, but he built the first affordable ones. It's the same with his computers, they were not the first on the market but they were the first that many people experienced because they were cheap.

      • Did he? I was under the impression that the HP-35 was only somewhat more expensive (~$US 2500 in today's value, compared to ~$US 1500 for the contemporary Sinclair Executive), while being significantly more useful.
        • I’m not sure I would call a 2/3 price increase only somewhat more expensive.
          • Is that after accounting for the difference in value between a four-function calculator and a scientific calculator
            • I’m sure the extra cost was well worth the price for those who required those features. I’m also sure a 2/3 price delta on an already pricy item is not somewhat more expensive.

    • by psergiu ( 67614 )

      https://en.wikipedia.org/wiki/... [wikipedia.org]

      The Sinclair Executive was the world's first "slimline" pocket calculator.

      ... typical for a C64-loving hater to speak denigratory words about Sir Clive and his wonderful inventions.

  • Timing. (Score:4, Interesting)

    by Ostracus ( 1354233 ) on Thursday September 16, 2021 @05:46PM (#61802711) Journal

    Coincidence. ZX(81).

    • by AmiMoJo ( 196126 )

      The first one was the ZX80, actually the second computer they made but the first that was a complete system we would recognise today.

      Some sources say the 80 was because it came out in 1980, but I think it's much more likely that the name is because it used the Z80 processor.

      The Z80 was an enhanced 8080 core, which itself was based on earlier designs that can be traced back to mainframes.

      • Re:Timing. (Score:4, Informative)

        by sg_oneill ( 159032 ) on Thursday September 16, 2021 @09:43PM (#61803207)

        Hmm. Im not sure of the mainframe lineage.

        The 8080 was an 8 bit version of the 4040 , itself an extension of the 4004, a 4 bit cpu that was probably the first generally available single-chip CPU.

        Where I think Sinclair fits into history, is it was absolutely the first affordable UK home computer, and several of the staff that worked on that went on to fom Acorn, which brought us the ARM cpu, which is now busy eating the world.

        • Comment removed based on user account deletion
          • by hawk ( 1151 )

            Yes, the 4004 and 8008, and then the 4040 and 8080, had little in common other than naming patterns.

            I've never heard of anyone trying to build a general purpose machine from a 4004 or 4040. Besides the 4 bit structure, it had separate execution and data, as well as other capacity limits.

            The 8080 was an evolutionary step forward from the 8008, which had only 14 bit addressing and an internal 8 layer stack of 14 bits each.

            The first issue of Byte I ever saw was at the Second West Coast Computer Faire, and it

      • Comment removed (Score:4, Informative)

        by account_deleted ( 4530225 ) on Thursday September 16, 2021 @11:41PM (#61803361)
        Comment removed based on user account deletion
        • by AmiMoJo ( 196126 )

          Indeed, I stand corrected. However the Z80 is more than just a reimplementation, it does add significantly to the 8080 architecture.

      • by kenh ( 9056 )

        The Z80 was an enhanced 8080 core, which itself was based on earlier designs that can be traced back to mainframes.

        No, it can't be traced back to mainframes - at least not in any meaningful way.

        Intel CPUs like the 4004, 8008, 8080, etc were unique unto themselves and upwards compatible, the Motorola 6800 and 68000 family of processors were "inspired" by the popular PDP-11 architecture

        • Incidently the 68000 series was actually competently made and more like a 32bit processor, than the weird crap Intel had wrought.

          • by hawk ( 1151 )

            in fact, when initially shipped, the 68000 data sheets *showed* the future expansion of registers to 32 bits as greyed areas!

    • I'm glad my most popular product was the "Tablizer 666".

    • Coincidence. ZX(81).

      If only he had just stopped after inventing the Timex Sinclair 1000 [wikipedia.org].

    • This one goes to 81.
  • Comment removed (Score:5, Informative)

    by account_deleted ( 4530225 ) on Thursday September 16, 2021 @06:01PM (#61802753)
    Comment removed based on user account deletion
    • by neilo_1701D ( 2765337 ) on Thursday September 16, 2021 @07:07PM (#61802909)

      And a fair number of us learned assembler on the ZX81 by literally creating a REM statement that had enough characters that we could use POKE statements to replace them with machine code instructions and fit the entire program in that REM! Yes, it was insane, but when you're using a computer with 1K of RAM and an 8K ROM including a floating point BASIC, you're not working with a lot.

      2A 0C 40

      To this day I can remember how to get the address of the display file into HL.

      • Comment removed based on user account deletion
        • Comment removed (Score:5, Interesting)

          by account_deleted ( 4530225 ) on Thursday September 16, 2021 @08:06PM (#61803027)
          Comment removed based on user account deletion
          • OK, OK, now I'm kinda excited - for those of you millenials etc who wonder what Gen X had to do to program a computer in 1982, here's a book on Z80 machine code [archive.org] that introduced many ZX81 programmers to something more "advanced" than BASIC...

            Yes! This was the first book I read once I graduated from BASIC.

          • For me it was the BBC Advanced User Guide [stardot.org.uk] which had a section that taught me 6502 assembly.
            • Comment removed based on user account deletion
              • The Raspberry Pi and Arduino are today's computers for the hacker/maker crowd. Obviously they're intended to be programmed in high level languages though.

                If you really want to go low level, there are still Apple IIs etc available on eBay.

              • by cusco ( 717999 )

                I think that the modern equivalent of this class of computers would be the burgeoning robotics hobbyist market. I'll be retiring in a couple of weeks and will finally have time to break into that field myself. I'm excited.

            • by AmiMoJo ( 196126 )

              The BBC Micro allowed assembler to be mixed with BASIC, which made it incredibly powerful and very easy to start using assembler. It was one of the fastest BASICs around to boot.

              Clive was very upset when the BBC went with the Acorn machine, not least because it had been developed by former Sinclair staff who were fed up with Clive and his ideas.

          • I lucked into a Timex Sinclair 1000 as a kid. I loved having my own computer, but it only had 3k of RAM, which was pretty limited for BASIC programming. I tried to figure out other things I could do with PEEK and POKE, but I was feeling in the dark, since there wasn't any info at my local library. I would have killed for this book around 1984!

        • THAT looked familiar! Did you perchance read Toni Baker's book on ZX81 machine code? I just found it listed on Amazon [amazon.com], and the author and the chapter list looks awfully familiar. Had a foreword from Tim Harnell IIRC, who was mostly known for hastily written "Learn BASIC on $COMPUTER" books...

          Toni Barker, Tim Hartnell... I've read the classics. Dr Ian Logan, of "Understanding your ZX81 ROM" fame, too.

          I invested into the ZX Spectrum Next kickstarter back in 2017. The machine they delivered is phenomenal... and I've be locating and re-buying much of the books from that era to get re-acquainted with ZX Spectrums, Z-80 assembly etc.

          Sir Clive may have had his RAM pack wobble at 81 (how fitting), but his legacy lives on. Just the number of people in these comments (and on Facebook, The Register etc

  • Micro Men (Score:5, Interesting)

    by seoras ( 147590 ) on Thursday September 16, 2021 @06:16PM (#61802799)

    Worth watching is the film Micro Men [imdb.com] starring Alexander Armstrong as Clive Sinclair and Martin Freeman as Chris Curry (BBC Micro).
    Can't vouch for its historical accuracy but it is very entertaining.

  • by mbeckman ( 645148 ) on Thursday September 16, 2021 @06:31PM (#61802827)
    My first Sinclair product was the astounding Sinclair Scientific calculator, which revolutionized my engineering education. It used RPN, with a sharp little LED numeric readout behind a very cool purple window. It could do complex number math using polar coordinates using its RPN operation stack, invaluable for my AC Circuit Analysis class. I bought the ‘48 later, and even though I was a mainframe programmer at the time, the thought of having this much algorithmic power on my TV was intoxicating. I would write simple basic programs for all kinds of iterative functions, but soon discovered what Feynman called “the computer disease”: spending all my time finessing code, and less and less solving actual problems :)
  • by iamnotx0r ( 7683968 ) on Thursday September 16, 2021 @06:56PM (#61802883)
    And... I got employed cause I answered interview questions on z80 by engineers. Sinclair got me my first job for 99$ from K-Mart.

    One of the best money I spent. I also had a 16k bill from getting a Physics Degree. That Timex paid off my loans, basically.
  • by jd ( 1658 ) <imipak@ y a hoo.com> on Thursday September 16, 2021 @07:16PM (#61802927) Homepage Journal

    A cheapskate inventor, in some ways, but still brilliant at times.

    I consider his transistor amplifier to be more radical than the ZX80. The former required clever thinking, the latter involved buying reject parts at bargain prices on the theory they'd work at the levels home users wanted.

    His greatest idea, IMHO, was to build wafer-scale memories. The idea was that as long as you could format the memory and mark sections as bad, it really didn't matter if the whole thing worked or not.

    This idea may have been the inspiration behind the 486SX, which was just a DX with a non-functional 487 component. Chips with bits disabled, so avoiding rejects.

    • involved buying reject parts at bargain prices on the theory they'd work at the levels home users wanted.

      Which is, of course, a clever idea.

    • by hackertourist ( 2202674 ) on Friday September 17, 2021 @05:32AM (#61803707)

      Much of his brilliance was driven by the cheapskate thing. He managed to get the cost of computers (and calculators) down to 'easily affordable' levels by finding out where he could cut corners, minimizing the number of components needed [righto.com] for his designs.

      In a hotel room in Texas, Clive Sinclair had a big problem. He wanted to sell a cheap scientific calculator that would grab the market from expensive calculators such as the popular HP-35. Hewlett-Packard had taken two years, 20 engineers, and a million dollars to design the HP-35, which used 5 complex chips and sold for $395. Sinclair's partnership with calculator manufacturer Bowmar had gone nowhere. Now Texas Instruments offered him an inexpensive calculator chip that could barely do four-function math. Could he use this chip to build a $100 scientific calculator?

      Texas Instruments' engineers said this was impossible - their chip only had 3 storage registers, no subroutine calls, and no storage for constants such as Ï. The ROM storage in the calculator held only 320 instructions, just enough for basic arithmetic. How could they possibly squeeze any scientific functions into this chip?

      Fortunately Clive Sinclair, head of Sinclair Radionics, had a secret weapon - programming whiz and math PhD Nigel Searle. In a few days in Texas, they came up with new algorithms and wrote the code for the world's first single-chip scientific calculator, somehow programming sine, cosine, tangent, arcsine, arccos, arctan, log, and exponentiation into the chip. The engineers at Texas Instruments were amazed.

      Similarly, the ZX computers had chip counts below what other manufacturers thought possible.

      IIRC he also found out how to drive LED displays in battery-powered devices with an acceptable battery life, by driving the LED in pulses instead of leaving it on continuously.

  • by rossdee ( 243626 ) on Thursday September 16, 2021 @10:14PM (#61803249)

    The C5 (a small electric car)

    • More an electric bicycle (tricycle factually). But yes, he did invent that too. Unfortunately, Li-Ion batteries hadn't been invented yet so he had to use Lead-Acid batteries which were too heavy and had too little energy storage to be useful for motorized applications.
    • by AmiMoJo ( 196126 )

      "Car" is pushing it a bit, the C5 was really a recumbent bicycle with battery power, and pedals for when the motor wasn't enough to get you up a slope.

      They are actually fairly simple machines, really just a scaled up toy car with a 12V lead acid battery and a throttle. The throttle was a binary on/off affair, there was no speed control other than by pressing and releasing it periodically.

      It could have been more successful if it hadn't been for the British press savaging it. The British press loves to destro

      • It could have been more successful if it hadn't been for the British press savaging it. The British press loves to destroy things. Nowadays electric bikes are quite popular.

        Oh come off it! Everybody savaged it, it didn't require the press to do so. After the initial disbelief when it was first launched, people in were in tears of laughter. As for electric bikes nowadays, that is because hipsterism has come along since.

        • by cusco ( 717999 )

          Actually it's because lithium batteries are now light enough and cheap enough to to be portable, and motors have advanced dramatically over the last decade. I stopped riding here in Seattle when my asthma woke up (if the hill we lived on existed in the Midwest there would be a ski resort on it). Electric bikes have now come down in price enough that I can start riding again.

  • Fond memories like several here. I could borrow a 1Kb ram zx81 from a friend and it changed my life. Making my first basic and then assembler programs, wonderful! It was a gamechanger because affordable for most parents. My next computer was a commodore 64 which had come down in price and I progressed from there.
    Something appealing about these machines was that you switched them on and started programming. No barrier, no steep uphill learning curve.
  • by dromgodis ( 4533247 ) on Friday September 17, 2021 @02:34AM (#61803503)

    I was mightily surprised to learn just recently that there is a demo scene on the ZX81 today, and would have been surprised back in the days if they had shown me what the machine is able to do.

    For example: https://www.youtube.com/watch?... [youtube.com]

  • Micro Men (Score:4, Informative)

    by johnrpenner ( 40054 ) on Friday September 17, 2021 @03:40AM (#61803593) Homepage

    Micro Men https://youtu.be/XXBxV6-zamM [youtu.be]

  • His computers from the early 80s gave me access to technology at a young age which I would not otherwise have had. No way could my family afford a C64 or BBC. His inventions put me and many others where I am today with a well paid job that is my hobby and my hobby that is my job.
  • I started with the ZX81 in 1981 at 10yo, my father soldered it because it was a DIY kit, he then bought the 16K expansion. I learnt BASIC on this, the rest is history!

  • It was the Amstrad, the CPC464 first, then the CPC6128, you had a real floppy drive (on a IBM interface, not on a 9600bauds serial port like the C64), a color monitor, etc, everything integrated.

    The Amstrad CPC is what killed the Spectrum and the Sinclair brand.

    • by larwe ( 858929 )

      The Amstrad CPC is what killed the Spectrum and the Sinclair brand.

      The CPC was slightly superior in graphics capability, basically identical in audio capability to the later Spectrum models with AY chips. What killed the Sinclair brand was Amstrad acquiring it. They were very similar computers occupying a very similar market segment, almost all software released to the 8-bit world was released to both platforms, so Amstrad was competing against itself.

    • Is that you Alan? The CPC was way late to the home computer market and a bit of an oddball. I'm sure those that had it it enjoyed owning it, but there were only really two players in the home computer market in the UK in the 80's the C64 and ZX Spectrum.
    • Comment removed based on user account deletion
  • His ZX-81 was my first computer, cassette tape drive and all.
    Hopefully his accomplishments get a place in the Museum of Science and Technology.

  • My first computer was a ZX81, my second a TS1000 (basically the same computer with a different name and a different base amount of RAM). The reason? I was a poor high school student: it was the only computer I could afford. Otherwise I would not have had a computer at all. So SInclair's obsession with low cost was exactly what I needed. The machine had lots of compromises, including a pretty awful membrane keyboard, but it worked well enough to learn on. Yes, like others I did buy a surplus mechanical keyb
  • Back then, it was a big deal to own one. Obviously by today's standard, they are junk, but back then, it was interest.

    RIP Sir Sinclair.

Understanding is always the understanding of a smaller problem in relation to a bigger problem. -- P.D. Ouspensky

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