Saturday, November 30, 2013

How YOU Can Memorize 2000 Digits of a Number

Since it is two days after Thanksgiving, and many of us are probably eating leftover pie, I thought it would be appropriate to do a post somewhat relevant to the numerical pi. And I could do something very mathematical, but I just finished my first trimester at Phillips Academy Andover last week, and I needed a break after my nearly impossible MATH-380 final exam. As a result, I thought it could be fun to talk about memorizing numbers, pi and tau in particular.

When people hear about my Tau 2000 event, they often ask me if I have what they call a "photographic memory." This is not at all true. I don't even think the types of photographic memories advertised in pop culture really exist (I'm not an expert on neurology, so for more on that, I'd recommend reading this Scientific American article). The way I memorized 2012 digits of tau was all learned and practiced techniques, similar to my mental math presentations. I was not born with some gift or natural talent, it was just learning the methodology and practicing until I could do it quickly. Just like anyone can do mental math, anyone can be a memory expert as well, ranging from being able to remember 57890 digits of pi to being able to remember your car keys as you leave for work. There are techniques for it all.

First, let me introduce you to the Major System. This is a phonetic code that enables you to turn numbers into words. You store them as words, and later retrieve them as numbers. Basically, each digit is associated with a specific consonant sound.

1 is the t or d sound. It can also be either of the th sounds (see note below).
2 is the n sound.
3 is the m sound.
4 is the r sound.
5 is the l sound.
6 is the j, ch, sh, or zh sound.
7 is the k or g sound.
8 is the f or v sound.
9 is the p or b sound.
0 is the z or s sound.
Note: th (both the th in "that" and the th in "thing") is normally paired with 1, but there are other variations on the system that will put it with 8 or not include it.

This looks hard to memorize on its own, but it is actually not that hard. Here are some mnemonics that can help you.
  1. A t or d has 1 downstroke.
  2. n has 2 downstrokes.
  3. A m has 3 downstrokes.
  4. The number 4 ends in the letter r.
  5. If you hold up your hand with 4 fingers up and your thumb at a 90° angle, you will see 5 fingers shaped like an L.
  6. A J looks somewhat like a backwards 6.
  7. A K can be drawn with two 7s back to back.
  8. A lowercase f in cursive looks like an 8.
  9. The number 9 is a backwards p or an upside-down b.
  10. The word zero begins with the letter z.
You will also notice that the consonants that were paired together sound very similar. Your lip movement and tongue placement are the same in any of the consonant sounds chosen for a number (except for the th sounds, hence the inconsistency of its use).

You might be wondering why there are no vowel sounds on the list. There is also no h, w, or y sound. This is because you can insert these wherever you want between consonants and they mean nothing. With all of this in mind, you can begin turning numbers into words. Let's take the number 15. What words can this become?

Well, one is the t or d sound. Five is the l sound. Insert vowels, and you can get doll. Or tile. Or tail. You can also insert vowels at the beginning or end of the word and make deli, or Adele. You can also insert hs, ws, and ys to get hotel, towel, or yodel. Here are a list of the 66 words that can be made out of  the number 15 (I put the ones that I might use in a mnemonic image in bold print):

Addle, daily, dale, dally, deal, delay, dell, dial, dole, doll, dual, duel, dull, duly, dwell, ethyl, hastily, hostile, hotel, hotly, huddle, ideal, ideally, idle, idly, idol, it'll, italy, oddly, othello, outlaw, outlay, saddle, sadly, seattle, settle, societal, stale, stall, steal, steel, still, stole, stool, style, subtle, subtly, suicidal, sweetly, tail, tale, tall, tally, teal, tel, tell, they'll, tile, till, toil, toll, tool, towel, waddle, widely, yodel
Note that some of the words start with s. Since s is zero, this is referring to the number 015, which is normally still 15. These words do not work if 15 is part of a string of other digits such as in pi or tau.

The ones that I bolded are all nouns that you can create a mental image of in your head. As the Scientific American article that I linked to states, people naturally have a better memory for visuals (the reason why you might remember someone's face, but not be able to place the name). So, you might not be able to remember the number 15, but you can probably picture a doll, or a hotel, or a yodel (for this, I would think of the chocolate pastry, not the verb). If you are trying to remember that it is someone's address or apartment number, picture a relationship between the object and the person. Maybe the person is standing up on a stool shouting to a crowd of confused, awestricken people, or they are on the couch stuffing their face with yodels. The sillier your image, the easier it is to remember.

There are lots of memory experts who will create a list of "peg words," which are essentially 100 words that they will refer to when they are trying to remember a number between 1 and 100. It is certainly not a necessity, but it can often help if you are trying to come up with a word on the fly. Every person has a different list of words that works for them, so this is something that I would encourage you to make on your own. The website works very well to help create this list.

To memorize shorter strings of digits (something like memorizing 100 digits of pi), the best approach in my opinion is to create sentences out of your words. For instance, take the first five digits of pi: 31415. The only word that can be formed out of this is moderately, which isn't a great start to a sentence. However, it could be turned into "my turtle" or "Madrid law" or "Mother Yodel." The first 24 digits of pi create the sentence:

My turtle Pancho will, my love, pick up my new mover, Ginger.

Say this a few times and you will sadly have it memorized. And since you now know the code, you now have the first 24 digits of pi memorized. If you want to keep going, the next 17 digits are:

My movie monkey plays in a favorite bucket.

The next 19 are:

Ship my puppy Michael to Sullivan's backrubber.

If you want to take it to 100 digits, you can use:

A really open music video cheers Jenny F. Jones.

And my personal favorite:

Have a baby fish knife so Marvin will marinate the goosechick.

This method works great for condensing large quantities of numbers into a small amount of silly, memorable sentences. However, once you get up towards 300, 400, 500 digits, it is really tough to remember the exact prepositions and linking verbs you used, which contribute to the digits. Because of this, the method I used for memorizing 2012 digits of tau is a different variation. Rather than just memorizing plain sentences, I used a technique called the memory palace.

A memory palace is essentially a place that you can mentally visualize that you put the images that you create in. For instance, your drive from your house to work might be a memory palace. Your elementary school campus could be your memory palace. You can even create an imaginary place to be your memory palace. Let's pretend your memory palace is inside of your house. The first ten loci (places to put the images) might be:
  1. Your bed (in your bedroom)
  2. Your closet
  3. Bathroom
  4. Hallway
  5. Other Bedroom
  6. Stairs
  7. Living Room
  8. Dining Room
  9. Kitchen
  10. Front Porch
And you might have a grocery list with the following items:
  • Grapes
  • Carrots
  • Corn on the Cob
  • Yogurt
  • Cheddar Cheese
  • Marshmallows
  • Cheetos
  • Salt
  • Pepper
  • Ice
All you need to do is mentally "put" each of these items into the corresponding locus in your memory palace. For instance, the first item is grapes. You would put the grapes on your bed. But you wouldn't just put them there, you must do something to make the image stand out. First of all, you must embrace the image. Not only do you see grapes, but you smell the grapes, you taste the grapes. The more of your senses that you alert, the easier the image is to remember. The image also needs to be less dull than just a few grapes sitting on your blanket. Maybe have grapevines growing out of the back of your bed. Maybe visualize the grapes to have legs, and jumping on the bed. As long as it is a silly image that stands out in your mind, you will be able to remember it.

The next item on the list is carrots. The corresponding locus is your closet. Carrots grow out of the ground, so maybe you picture all of the mud that your sneakers have tracked into the closet has carrots growing in it. As long as you pull a carrot out of the mud, you will remember it is carrots. Or maybe there is a snowman inside with a carrot nose, or a carrot shoe-horn. The actual carrot aspect of the image can absolutely be subtle, as long as you can remember the image and this image triggers the thought of carrots in your mind.

Continue through the list, and you will have ten images in your head that will in fact be stuck there until you use other techniques to remove them (yes, there are techniques people use to forget things). Try this out a few times, and I'm sure you will find it very useful. If you have a list of things to do at work, you need to remember when to pick up your kids and bring them to their activities (you may even use the major system for translating times into words - if you need to bring your son to baseball practice at 4:15, you may just picture your son swinging his bat at a "hurdle" (r=4, d=1, l=5) in the appropriate locus), or anything else, the memory palace is a great way to go.

How does this help one memorize the digits of a number, like tau? Well, what the major system does is turns numbers into words, which can then be turned into images. The memory palace then acts as a place holder for those images. For instance, take the digits of tau:


The first two digits are 62. What words can this form? You can say chain, gin, maybe you know someone named Jane or John. I ended up choosing the word ocean.

The next three digits are 831. This forms the word vomit. Yes, it is disgusting, but it is a word that will create a memorable image.

The next two digits are 85. From this, we can create the word waffle. So the first image will be "an ocean vomiting a waffle." It sounds very silly, but it will be memorable. The smell of the saltwater, the taste of the waffles, the sound of the ocean waves crashing. This all will go into your first locus. My memory palace for tau was my middle school campus, so I remembered this image in the back parking lot of the school.

The next image is comprised of the digits 30717958. This can be turned into "a mask tugging on a bailiff." This was put inside of a staff room that the back parking lot has a door to. It is a very weird image, but still memorable. Picture the bailiff really struggling to get away from this mask, while still fearfully reciting his lines: do you solemnly swear to tell the truth, the whole truth, and nothing but the truth. Make yourself feel scared of this moving mask, and sympathize with the bailiff. The more you relate to and embrace the image, the more memorable it will be. Especially when you are memorizing 2012 digits of tau (which took me 272 images), you need each image to be extremely vivid.

To retrieve the numbers from this memory palace, all you do is go back to the image, find the subject, root verb, and object of it, and translate the consonants back to numbers with the major system. With practice, this becomes easier and easier to do. I strongly recommend practicing at least memorizing grocery lists and to-do lists with the memory palace, and if you want to take it further, learn to convert numbers to words with the major system for more advanced lists and situations. Maybe even memorize your family and friends' phone numbers with the major system and memory palace. These are all great exercises for your mind, and will definitely give you a better memory.

1 comment:

  1. Wow...I never knew you could go to 2012 digits with such a technique. My memory is naturally good (I have a way with numbers), so I played to my strengths and while memorizing pi, e, and sqrt(2), used a 4-number combination technique. Here's how it went:

    Took the digits of e (the first number I memorized, so will use as an example here) and broke it up into groups of four (200 digits for reference here):

    2.7 1828 1828 4590 4523 5360 2874 7135 2662 4977 5724 7093 6999 59574 9669 676 2772 4076 6303 5354 7594 5713 8217 8525 166 427 4274 6639 1932 0030 5992 1817 4135 9662 9043 5729 0033 429 5260 5956 3073 8132 3286 2794 3490 7632 3382 9880 7531 9525 10190 11573

    Now, memorizing straight through, four numbers each, is very difficult and probably impossible after 1,000 digits. So every so often I would stick in sequences of 5 or 3 that made sense. "Making sense" in this method meant having sequences that were easier to remember. Consider:


    Under standard 4-digit breaking up you would get: 5957 4966 9676
    But that's hard to remember, so instead put in a sequence of 5 in order to have the surrounding sequences "make sense:"

    59574 9669 676

    Now we have a palindromic "9669" and "676," and this double palindrome quality helps me memorize better. Furthermore, the unusual "59574" and "676" break the monotone rhythm of 4-digits at a time, which helps act as a benchmark to get back on track if you were wandering off. I usually put in these whenever it makes sense or every 50 digits so I don't wander. This technique has helped me get hundreds of digits of pi, e, and sqrt(2) memorized.

    Maybe I will try tau next with this method...