How to Create Bulletproof Knowledge

Have you ever noticed that whenever a favorite song of yours comes on the radio, memories from what you were doing then flood back to you at that moment, like you’re experiencing it all over again?

My wife and I go married over a year ago, but as soon as our wedding song comes on (Zac Brown Band’s “Free”), I remember the room, the people, the food, the smells – and of course the exact super-sweet killer dance moves I put on display for the cheering crowd.

Photo: quickmeme

When it happens it’s like you’re time-traveling and everything is happening real-time in vivid detail. A perfectly recollected memory – and it all happens automatically.

Contrast that to the moments when you feel like you ABSOLUTELY MUST remember how to do something…

  • How to change a tire on the side of the road when you get a flat
  • How to make your grandma’s famous soup recipe when you have a group of family and friends over for dinner
  • How to solve a tough integration problem on your Calculus final when you need an 83% to pass the class

Why is it so hard to remember the these things when you need them the most?

The myth of the quiet study place

It turns out there’s actually a reason I can remember everything about my wedding when I hear Zac Brown, but can’t seem to remember anything at all about the Mean Value Theorem from calculus class – and it has to do with some weird features of how our brain encodes new memories.

We all know the typical advice when you need to get “serious” about studying something so you can remember it reliably later:

“Go and find a quiet place where you’re free of distractions, sit down, get out your books, and put in the study time.”

And we even have little phrases that we tell ourselves when it comes time to learn something new:

“I just need to buckle down and focus.”

“I just need to go lock myself in a room until I get this stuff into my head.”

Well in 1985, Steven Smith – a researcher at Texas A&M – actually put this advice to the test.

He had students study a list of 40 vocabulary words in 3 different environments: (1) listening to jazz music, (2) listening to classical music, and (3) sitting in silence.

He then tested those same students 2 days later, this time varying the test environment into the same 3 categories, but mixing it up (so the jazz studiers were tested in a jazz, classical, and silent environment – and so on).

The results were pretty friggin’ weird.

The students who studied and were tested in the same music environment remembered ~21 words (50% correct) on average (e.g. studied with jazz, tested with jazz). However, when the environment was changed, either to a different type of music, or to silence, they only remembered ~10 words (25% correct) on average.

So Smith was able to show that, at least with a straight memory recall test, you’ll perform up to 100% better if you take the test in the same environment that you studied in – but with a catch…

The students who studied in silence only remembered ~10 words IN ALL TEST ENVIRONMENTS, even when tested in silence.

Sorry WHAT?? This is not what they’ve been telling us…

Photo: quickmeme


As Benedict Carey lays it out in his bestseller, How We Learn,

“Having something going on in the study environment, like music, is better than nothing (so much for the sanctity of the quiet study room).”

The reason this is true?

It all has to do with the CONTEXT around what you learn. The sounds, smells, environment, people, emotions, etc.

And this is the problem with the “quiet study place” advice, and is much of the reason why our knowledge fails when we need it most.

Want to remember what you read? You’re better off doing it at the beach or pool than at home in silence.

Want to be able to better communicate to your boss or clients what you’re working on? You might be better off working on it in a bustling coffee shop instead of a quiet conference room at the office.

And on top of that, not only do interesting and diverse environments provide context for memories to “attach” themselves to, they also provide intrigue and emotional fodder that prompt us to continue to think about those things we want to learn long after the one time we actually sat down to learn them – a compounding effect.

This is why I remember the people, the dancing, and the environment of my wedding reception when I hear that song – the music is the context in which my brain has encoded those memories. Not so with the Mean Value Theorem, which I’m sure I copied down off of a chalkboard at some point, but can’t remember when, where, or why I would possibly need to care.

Context Varying: How to produce robust knowledge you can take with you anywhere you go

So what can we do with this?

The problem for us in most cases is the way we generally learn new skills isn’t organized around these principles. We go to lecture, where everyone is silent, and focused, and then go to the library to study, where again, everyone is silent and focused. Unfortunately, that lack of context and lack of stimulation is hurting our ability to recall that information later on.

All too often we know the guy who is great during practice, but then can’t perform come game time. The guy who can hit 1,000 foul shots in a row in the quiet, calm gym, but can barely manage 50% of them during the game with the opposing team’s fans screaming at them.

Photo: Jeramey Jannene


We can think of our preparation in school for a test, or preparation at work for the big presentation in the same way. The key knowledge you’ve acquired along the way that you need in order to perform or solve problems in real time needs to be available to you in any number of diverse situations.

So instead of pigeon-holing ourselves, only able to remember or perform in the very specific context in which we usually practice, we need to make our knowledge more robust.

In a separate study that Smith (mentioned above) and two other researchers conducted at the University of Michigan, they were able to show that by making a simple change in environment during the study process, memory retrieval performance was improved by 40%.

As Carey puts it (again from How We Learn),

“We can easily multiply the number of perceptions connected to a given memory – most simply by varying where we study… Each alteration of the routine further enriches the skills being rehearsed, making them sharper and more accessible for a longer period of time… makes what you know increasingly independent of your surroundings.”

Variety is the spice of life. And it’s also the basis of what I’m calling The Bulletproof Knowledge Protocol.

The Bulletproof Knowledge Protocol

To combat this problem, let’s take whatever you’re trying to learn and give it a major “context upgrade.”

Let’s say you’re studying for a Calculus exam that’s scheduled for next week. You want to be as prepared as possible, and have a few hours to spend over the next 3 days to study.

Step 1: Organize your study routine around Active Recall practice.

The foundation of super-robust knowledge acquisition is training yourself to be able to recall the information you need off the top of your head. This is much different than simply being able to understand what’s going on.

So to operationalize the material you’ve learned, you’ll want to organize your study routine around Active Recall practice, which boils down to 3 essential steps:

  1. Identify a set of problems you’re trying to learn for the first time, or have been having trouble with. These can be homework problems that are assigned; however, you really want to have the full solution available afterwards so that you can check your work and see where you went wrong when you inevitably do.
  2. Hide the solution, and start solving from scratch. Don’t do any notes or textbook review before or during this process – no supporting materials. You need to force yourself to active your long-term memory to solve the problem – this is what creates rock-solid problem-solving ability later on down the line.
  3. Finish strong and check your work against the solution. Go through each step and verify that you had the correct method, starting at the final answer. Each mistake you make is an opportunity to improve, so don’t get discouraged – this is the best feedback you can possibly give yourself.

All of our knowledge-acquisition sessions should be based around this methodology.

Step 2: Select 3 different contexts in which you’ll solve problems and prepare for the exam.

Now generally, these might be 3 different locations (e.g. a lecture hall, the gym, the cafe), but context can also mean mood or time of day, or even the day of the week.

Photo: Terry Johnston


We could walk around holding our study materials, or review problems on a treadmill. We could review notecards in-between weightlifting sets or during TV commercials. We could even (like in Smith’s study) play a varied collection of music during different study sessions.

The combinations are endless, so get creative and pick something that works best for you.

Step 3: Do your Active Recall sessions in a different “context” each day.

Once you have your plan laid out, it’s just a matter of executing, so let’s organize our study contexts as follows:

Thursday – First work through practice problems at the dining hall during dinnertime (where it’s noisy and distracting). This is also after a long day of classes when you’re a little more mentally exhausted than usual.

Saturday – Your second study session, this time at the gym. You go first thing in the morning right after you get up, and are still a little groggy. You’re walking on the treadmill and have a set of 30 problems you’re going to work through using Active Recall. Because you’re moving your body (and there’s probably some background music), this will be a little more difficult than usual, but that’s a good thing for robust knowledge-building.

Sunday – Your third and final study session before the exam next week. This time you’re headed to the empty lecture hall in which the test is going to be held. You have a set of problems to work through that resemble the type of problems you’re going to see on the exam, and you’re sitting in your uncomfortable seat, replicating the actual test context as closely as possible.

Make it through this self-created gauntlet, and test day will seem like a walk in the park.

Congrats. You’ve built yourself some “bulletproof” knowledge.

Upgrade your study routine.

Now, this is a powerful principle I’ve outlined here, and if you can incorporate it into your learning routine, you’ll be that much better off.

But often times, we read about cool techniques like this, and then simply move on to the next thing, wondering why months have gone by without anything changing.

What we really need to do is put this stuff into PRACTICE, and as we all know, this is often the hardest part.

For you students out there, I’ve put together a free 5-Day No-BS Study Tactics Crash Course specifically for you, that goes beyond just outlining a “should-do” technique like I have here today.

Five emails over the next 5 days that will jump-start your academic performance.

We’ll go through a different aspect of the learning process each day, including:

  • How to set up bulletproof study routines
  • How to develop a deep understanding of new concepts
  • How to successfully prepare for exams without spending hours at the library
    and more…

So not only will we go through the action steps you’ll need to follow to implement a routine like Context Varying into your schedule, but we’ll also cover the other aspects of your study process that will earn you the grades you deserve, rather than leaving you wondering what happened.

Don’t wait until you get your first exam grade back to decide to improve.

Sign up for the free 5-Day No-BS Study Tactics Crash Course here, and I’ll send you the Day 1 email immediately.

You in?

Feature Image: Seth Capitulo


Tom is an engineer and physics tutor obsessed with independent learning. He writes about unconventional study methods at WTF Professor, aimed at simplifying the learning process for engineers and technical students.


Erin shows overscheduled, overwhelmed women how to do less so that they can achieve more. Traditional productivity books—written by men—barely touch the tangle of cultural pressures that women feel when facing down a to-do list. How to Get Sh*t Done will teach you how to zero in on the three areas of your life where you want to excel, and then it will show you how to off-load, outsource, or just stop giving a damn about the rest.

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