Okay, so I memorized 10,000 digits of Pi. How did I do that?

Here's how.

I started about 4 weeks prior to the test date (Watch here if you want to see me fail the attempt: https://www.facebook.com/ExtremeMemory), which isn't really a lot of time to learn 10,000 of anything. Actually, in hindsight, it was really a stupidly short amount of time to have agreed to. I think I would have needed a solid 6 weeks of studying to really have it down COLD. 4 weeks was really a tad short.

Now, to be clear, I didn't spend all 4 weeks memorizing. I actually memorized the 10,000 pretty quickly, in a grand total of 10 hours, maybe even less (about 1,000 digits/hour). What took so long was the review; making sure that I knew every single block of digits like my best friend.

The Challenge

What makes this particular Pi challenge interesting is that it's not your normal recitation of Pi from digit 1 to digit N. Rather, it's a timed challenge where you're quizzed on randomly selected 5-digit segments within the N digits of Pi that you memorized.

Why 10,000? Well, because as you can imagine, in such a massive amount of digits, you're bound to have 5-digit segments that are repeats (24 repeats, to be exact). Past 10,000 digits, these "collisions" explode and get out of hand.

The exact record is this:

The record breaker must correctly identify and recall 50 randomly chosen 5-digit segments in the shortest amount of time. "Identify and recall" means to say the 5-digits that come after and before the chosen sequence.

So for example:

Judge: "38095"

Me: "25720 and 01989"

(that's at the 1000th digit mark, in case you wanna check).

So 50 of those, without a single error, as fast as possible. The current record stands at 16 minutes and 38 seconds, by Memory Grandmaster Kevin Horsley of South Africa. 16 and a half minutes doesn't sound very impressive at first, but when you divide by 50, that gives about 20 seconds per segment. That's 20 seconds for the judge to say the segment, for the record breaker to think and locate the segment in his mind, then for the record breaker to say the 5 digits after and before. Not a whole lot of time, which is why knowing all 10,000 digits like your best friend is super important. You have to be able to recognize them and say the correct digits almost instantly to break the record. Ouch.

The Game Plan

I've memorized large amounts of data before, but nothing ever like this. The most I've ever had to hold in my head at one time is for the 1-hour disciplines at the World Memory Championships: 20 decks of cards or 2000 digits. But 10,000 digits? Never.

The first thing I had to do was figure out where I was going to mentally store them. I have a lot of memory palaces for training and competitions, but not many for storing long term data. Since the challenge requires the digits to be broken down into 5-digit segments, that meant I would need 2000 locations in a memory palace (or multiple palaces).

I decided to go about it 1000 digits at a time. 10 independent memory palaces, each with 200 locations, to store 1000 digits at a time. This was going to be the trickiest thing. At the moment I started, the longest journey I had was 60-80 locations long. 200 was going to be tricky. I also didn't want to use my training journeys because, well, I'm training with them. I needed totally fresh ones. So I sat down and brainstormed 10 meaningful locations that I had yet to use as memory palaces.

I came up with:

1. My high school, 2. Downtown Miami, 3. Key Biscayne, 4. In-laws house, 5. My new apartment building, 6. Coral Gables, 7. Trek to Everest Base Camp, 8. Kathmandu, 9. My parents' new house, 10. Florida Keys.

Okay, that was easy. Now 200 locations in each....yuck.

I struggled with the first two journeys. It was just so crazy how long and expansive these journeys had to be in order to cover 200 locations. But on the 3rd and 4th I tried a different approach, shrinking myself to a miniature version of myself and traversing over much smaller spaces. For example, my In-laws house, I used every single piece of furniture - light switch on the wall, carpet corner, door and door handle, etc. - as locations. It was a very tightly-squeezed-together memory palace. But I managed to fit 200 loci into one house! Cool. It actually worked really well.

After that point, it started to get easier and less daunting to create such massive memory palaces and I was able to finish up my 10 journeys shortly thereafter.

Next was to encode the numbers into images.

My Number System

I use a 3-2-3 number system (person / action / object). But with 5-digit segments that wasn't really going to work. Instead, I decided on 3-digit person and 3-digit object, overlapping that middle digit (the last of the first 3 and first of the last 3).

Ex: 14159 => 141 - 159 => Sam Neil in an Iron Man suit

Next, I wrote some software to encode the digits for me straight into the words they represent. I did this to save time. I could have read through all the digits but it was way quicker to already have the images encoded. So I programmed 10 lists of 200 images, person / object.

Memorizing Them

Next step was to memorize those lists. I mean, that was the whole point, right? So list by list, 1000 digits by 1000 digits, I read through them, visualized them, placed them in my memory palaces, then went through them again. That was typically enough to make 90% of them stick. I was actually amazed at how easily they stuck. Of course there were sections that were weaker than others, but I'm confident to say that with just 2 passes through each, I had at least 85-90% of them stuck in my head. MEMORY TECHNIQUES FTW!

I had two weeks left at this point. Again, while it may have taken me at MOST, 10 hours to memorize it all, that wasn't a continuous 10 hours. I probably went for 1000 digits a day (an hour a day), with a rest day here and there. The remaining two weeks were devoted to reviewing for an hour a day. Some times I'd just re-read through the lists, other days I'd try and recall the entire lists from memory (no peeking), other days I'd train with some software that I had created that quizzed me.

Again, I always felt like I had most of them. In similar words to Anchorman, "I could recall 90% of the answers right 100% of the time." It was easy to mis-recall a single digit or skip over a tucked away location in one of those long journeys. I likened the whole review process to spinning 100 plates on sticks. You're frantically running around trying to keep them all spinning but by the time you get done correcting a few over here, no matter how on top of it you are, there are always others over there that are on the verge of falling.

Then the last week I honestly started freaking out, second-guessing myself. Do I really know ALL of them? What about this section? Try and recall it, go! Oh you can't, better review it! What about this other section?  Etc. And then it just felt like I was cramming.

The Day Of

For the day of the event, I flew to San Diego to perform the attempt live at Dart NeuroScience (where the last 3 XMT's have been held). Fellow memory athlete, Brad Zupp also had trained for this and was joining me as well. The goal was, of course, to try and break a record, but more importantly to raise awareness for World Alzheimer's Day and the Extreme Memory Challenge (a massive long-term memory research project by Dart).

We each got 3 attempts, alternating. My first attempt, I made it through about 11 correct, then stumbled on the 12th. Attempt #2 I made it through about 13 before saying a wrong digit (I knew the correct digit, just said the wrong one, whoops). The last attempt was a lack-lustered finale as I made a single digit error on the very first one. Brad didn't do any better. Ufffff....

What's Next

While all of our attempts were in a sense "not even close," I still feel like I can do the challenge and had even done it a couple times perfectly (in world record time) at home. I think a lot of it came down to luck. Were the judges going to choose more of the familiar 5-digit segments vs. the more unfamiliar ones? The end point here is that none of the 5-digit segments should be unfamiliar. I need to know them ALL equally well. I think another week or two of studying would have gotten me there.

Anyways, it was a very cool project for me. Got me back into training my numbers again and it challenged me to create a TON of new journeys, which I can now use for other training. I have a feeling I'll want to attempt this record again soon. Pi day 2017, anyone?

To watch a video recap of the event, check out Luis Angel's video: