https://susam.net/assoc.html Associations From IBM CGA Colours to Mnemonic Systems By Susam Pal on 07 Feb 2025 This is a vanity page that records some of the associations between various numbers, colours, and phonemes as they appear in my mind. I must mention here that I do not have synaesthesia. Many of these connections were shaped by childhood experiences. Notably, two unrelated influences, learning about computers and studying mnemonic systems, have played a significant role in forming these associations. Contents * Association Table * IBM CGA Colours * Phonetic Number System * Colourful Words * More Examples * Story Time * Conclusion Association Table The following table presents a quick summary of the associations between numbers, colours, and sounds. The sounds in the third column are represented using the International Phonetic Alphabet (IPA) notation. Number Colour Sound 0 Black /s/, /z/ 1 Blue /t/, /d/, /th/, /d/ 2 Green /n/, /NG/ 3 Cyan /m/ 4 Red /r/ 5 Magenta /l/ 6 Brown /tS/, /dZ/, /S/, /Z/ 7 White /k/, /g/ 8 Gray /f/, /v/ 9 Light Blue /p/, /b/ 0xA Light Green - 0xB Light Cyan - 0xC Light Red - 0xD Light Magenta - 0xE Yellow - 0xF Bright White - You might notice that the shade chosen for white in the table above looks more like grey. That's because it approximates the colour of white text on IBM CGA monitors. On a bright white background, this shade indeed appears grey. However, on the dark backgrounds common in early computing, it looked white, as demonstrated in the screenshots in the next section. I should clarify here that the associations for the hexadecimal numbers 0xA to 0xF are rather weak in my mind. I rarely ever have a need to think about them in my day-to-day life these days. But the associations for the numbers 0 to 9 remain fairly intact. IBM CGA Colours The number-colour associations in the assocation table come from my early exposure to GWBASIC running on IBM machines with Colour Graphics Adapter (CGA) and Enhanced Graphics Adapter (EGA). On these systems, each supported colour was represented by an integer code: 0 for black, 1 for blue, 2 for green, and so on. A screenshot of a GWBASIC program demonstrating the 16 colours in SCREEN 0 GWBASIC program demonstrating the colours supported in SCREEN 0 On IBM CGA machines set to video mode 3, each colour was encoded as a 4-bit number. From the most significant bit to the least significant one, the bits represented intensity, red, green, and blue (IRGB). For example, the number 1 (binary 0001) represented blue whereas 9 (binary 1001) represented light blue. Further, CGA monitors had special circuits to treat colour 6 differently. Normally, the number 6 (binary 0110) would represent yellow since the red and green signals are turned on. However, the special circuit of CGA monitors reduced the amplitude of the green signal to make the output look brown instead of yellow. The EGA machines supported a total of 64 colours but only a maximum of 16 colours could be used at a time. These 16 colours formed a customisable palette, with the default palette being backward compatible with CGA. Programs that wrote text directly to video memory at address B800:0000 also used these integer codes to display text in different colours. A screenshot of a DEBUG.EXE session demonstrating the 16 colours supported by IBM EGA machines DEBUG.EXE demonstrating the colours supported in MODE 3 I still fondly remember the excitement of using colour commands to paint the background blue and write text on it with various colours. That early experience left me with a preference for certain numbers corresponding to certain colours. Because of this, I find it a bit disconcerting that ANSI control sequences, in a way, use the least significant bit to represent red rather than blue. A screenshot of a shell commands demonstrating the 16 ANSI colours Demonstration of colours produced by ANSI control sequences In ANSI control sequences for select graphic rendition (SGR), the parameter value 31 represents red, 32 represents green, 33 represents yellow, 34 represents blue, and so on. I find this reversal of the order of colours a little unsettling. Phonetic Number System The number-sound associations in the association table come from a phonetic mnemonic system I learnt as a kid. I first discovered this system in a book on memory techniques by Harry Lorayne, which I had borrowed from a friend. This mnemonic system assigns a specific set of consonant sounds to each number. The vowel sounds play no role in this system. As we can see in the table, the sounds /s/ and /z/ are assigned to the number 0, the sounds /t/, /d/, /th/, and /d/ are assigned to the number 1, /n/ and /NG/ are assigned to 2, /m/ to 3, /r/ to 4, /l/ to 5, /tS/, /dZ/, /S/, and /Z/ are all assigned to 6, /k/ and /g/ are assigned to 7, /f/ and /v/ to 8, and finally, /p/ and /b/ to 9. There is also a meta-mnemonic system that provides some visual cues to remember these assignments. I'll briefly describe it here. The letter "z" is the first letter of "zero" (0). Typewritten "t" has one downstroke (1), while "n" has two (2), and "m" has three (3). The letter "r" is the last letter of "four" (4). "L" is the roman numeral for 50. Typewritten "g" when turned around looks like 6. "K" can be imagined as two 7s placed next to each other, with the top one flipped. A cursive "f" has two loops, just like the shape of 8. Flipping "P" horizontally makes it look like 9. While helpful in the beginning, this meta-mnemonic system becomes unnecessary as one gains fluency in the phonetic number system. The meta-mnemonic system is not the focus of this article. I'll focus solely on the phonetic number system here. Since there is a set of consonant sounds assigned to each number, this system allows us to translate words and sentences to numbers and vice versa quite easily. For example, the word "train" becomes the number 142. The number 3402 may be translated to the words "more sun" or "mario zone" or whatever else comes to your mind for the sounds /m /, /r/, /s/ or /z/, and /n/ or /NG/. Although the primary purpose of this mnemonic system is to translate numbers to memorable words and then later recall the numbers by reversing the process, frequent use of this technique in my childhood days had an unintended side effect. My mind began instinctively translating arbitrary words into numbers. While this effect has weakened with age, it still lingers, especially when I read signboards, product labels, street names, etc. The reverse effect remains as well. For example, if I look at bus route numbers, flight numbers, dates, etc. my mind automatically converts them to matching words. Colourful Words Although there is no direct mapping between colours and sounds, they can be linked indirectly. Each consonant sound is associated with a digit and each digit is associated with a colour. As a result, each consonant sound is indirectly associated with a colour. For example, the word "planet" can be translated to 9521. The colours associated with this number are light blue, magenta, green, and blue, respectively. The word "planet" is thus visualised as 9521 or PLANET. My name "Susam" becomes 003 or SUSAM. It is mostly black and a little bit of cyan. Apparently, my name isn't bursting with colour. I do like the cyan in it though. I quite like the fact that my initials "SP" translate to 09 and SP, as they contain my favourite numbers, 0 and 9, along with my favourite colors, black and light blue! As another example, the word "hydrogen" is visualised as the number 1 462 or the coloured word HYDROGEN. The colours here are blue, red, brown, and green. Similarly, the word "computer" is visualised as the number 7391 or the coloured word COMPUTER. The colours here are white, cyan, light blue, and blue. In case you're wondering why the final "r" is not visualised, that's because I do not always pronounce it. More Examples The list below presents some more examples of words, numbers, and their colours: APPLE 9 5 BLUE 95 CAT 7 1 DIGIT 1 6 1 Note that the "pp" in "apple" is pronounced as /p/, which corresponds to a single number 9. That's why "apple" is translated to 95 (not 995). There is also a certain harmony in the second example. The word "blue" begins with blue! ENOUGH 2 8 FUNCTION 8 276 2 GREEN 74 2 HOME 3 The "gh" in "enough" is pronounced /f/, so it is assigned the number 8. Likewise, the "ti" in "function" produces the sound /S/, which corresponds to the number 6. ICE 0 JUNE 6 2 KNOWLEDGE 2 5 6 LONDON 5 21 2 The "c" of "ice" is pronounced /s/, so it is assigned the number 0. It is interesting how a long word like "knowledge" yields a small number like 256. MATHEMATICS 3 1 3 1 70 NUMBER 2 39 OXYGEN 706 2 PARADOX 9 4 170 The "th" in "mathematics" produces the sound /th/, which corresponds to the number 1. The word "number" has the number 239. Like I mentioned earlier, I do not always pronounce the final "r", so I do not assign a number to it. However, someone who does pronounce it might assign 2394 to the word "number". The "x" in "oxygen" and "paradox" requires some discussion. In both words, the "x" is pronounced as /ks/, so the number 70 is assigned to it. The colours associated with 70 are white and black. While I personally visualise "x" in black in this case, its connection to both white and black is represented by a grey gradient in the above list. QUIZ 7 0 RED 4 1 SILICON 0 5 7 2 TINT 1 21 The word "red" begins with red! The "c" in "silicon" is pronounced /k /, so the number 7 is assigned to it. UNIVERSE 2 8 40 VINTAGE 8 21 6 WIND 21 XENON 0 2 2 YACHT 1 ZERO 0 4 Here, the "x" in "xenon" is pronounced /z/, so it is assigned the number 0. It is interesting how the entire word "yacht" reduces to the single-digit number 1. Story Time Do these associations offer real benefits in daily life? I doubt it. Even if they do, I'm sure the advantage is not too significant. However, they do make arbitrary numbers, words, etc. more engaging and vivid. That said, they can sometimes be surprisingly effective in retaining obscure facts for a very long time. Let me share a few examples in the next few sections. Bus to the Isle One way to travel from Dalston to the Isle of Dogs in London is by taking bus 277. However, if you don't use this route frequently, you might forget the route number after a few months. Even if you vaguely recall it, there's a chance for confusion. Was it 227? Or 277? Or maybe 217? This is where number-sound associations can come in handy. When I first stumbled upon this bus number, the following words immediately popped into my mind. NEW COOK 2 7 7 There is bit of green and there is a "new cook". It is not hard to link this colour and the words to the route with some playful imagination. Perhaps this bus delivers a new cook every week to a picturesque island filled with cheerful dogs. This cook, sporting a dull stone hat, arrives with one mission: to prepare fresh vegetables for the dogs! The scene does not need to make logical sense. In fact, the more absurd it is, the easier it is to remember! Now anytime, we think of Dalston and Isle of Dogs, we might recall dull stone and an island filled with cheerful dogs, and that might immediately remind us of the new cook who must prepare green vegetables for the dogs. We now have everything we need to reconstruct the bus number. We can translate "new cook" to 277. The fact that 2 is associated with green serves as an additional confirmation if we recall that the new cook's task is to cook green vegetables. Flight to Boston My first international trip was to Boston more than 14 years ago. I flew to Boston on flight BA 215. I still remember that flight number because when I first saw it, the following translation came to mind: ANT HILL 21 5 The departure time was 16:25 which brought up the following translation: TAJ NILE 1 6 2 5 Perhaps the boss of the flight crew lives in an ant hill and holds the world record for the fastest flight from the Taj Mahal to the Nile! Now Boston might remind us of the imaginary boss. What's peculiar about this boss? The boss lives in an ant hill which we translate to 215. The boss also holds a world record reminding us of Taj and Nile which we then convert to 16:25. Conclusion At the end of the day, these number-colour-sound connections are part of a little personal habit of mine. I do not rely on them every day but they do make arbitrary words and numbers more memorable. They weave a layer of imagination into the mundane. This quirky habit may not serve any real purpose but it certainly makes ordinary information more vivid and interesting. --------------------------------------------------------------------- Home Links Feed Subscribe About GitHub Mastodon (c) 2001-2025 Susam Pal