How to Actually Understand Anything (Not Just Memorize It)

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Hi, this is Ray,

And yes, I'm writing this after completely embarrassing myself trying to explain what photosynthesis is to my 10-year-old cousin.

I thought I understood it. I'd memorized it for biology class. I could recite the formula. I'd passed the test.

But when she asked me to explain it "like, what's actually happening?" I froze.

"Well, uh... plants use sunlight to make... food? And there's chlorophyll involved? And... carbon dioxide becomes oxygen somehow?"

She stared at me. "But how?"

I had no idea.

That's when I realized: I'd memorized information without understanding it. I could repeat words, but I couldn't explain the actual process.

This is the trap most of us fall into. We collect facts, memorize definitions, cram formulas… and think we're learning. But memorization isn't understanding. And understanding is what actually sticks.

Then I discovered the Feynman Technique, named after physicist Richard Feynman, who was famous for being able to explain quantum mechanics to regular people.

His secret? He didn't just learn things. He learned them well enough to explain them simply.

Here's how to use his method to actually understand anything you're trying to learn.

The Difference Between Memorization and Understanding

Let's start by exposing the lie we've all been taught:

School rewards memorization and calls it learning.

You memorize dates for the history test. Formulas for the math test. Definitions for the vocabulary quiz. You regurgitate them on the exam, get your grade, and forget everything by next month.

That's not learning. That's information rental.

Real learning (understanding) is different:

• You can explain it in your own words

• You know why something works, not just that it works

• You can apply it to new situations

• You can teach it to someone else

• You remember it months or years later

Research in cognitive science distinguishes between these as "rote learning vs. meaningful learning." Rote learning creates fragile memories that fade quickly. Meaningful learning creates durable knowledge that transfers to new contexts.

Here's a test: Can you explain why the sky is blue?

If you answered "because of Rayleigh scattering," you've memorized a term.

If you can explain that sunlight contains all colors, shorter wavelengths (blue) scatter more when hitting air molecules, so blue light bounces around the atmosphere reaching our eyes from all directions… now you understand it.

The Feynman Technique forces you to move from memorization to understanding by making you explain concepts simply.

Next time you study something, ask yourself: "Could I explain this to someone who knows nothing about it?" If not, you don't understand it yet… you've just memorized words.

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What Is the Feynman Technique?

Richard Feynman was a Nobel Prize-winning physicist who had an uncanny ability to explain complex ideas simply. Colleagues would often ask him to explain their own research back to them because his explanations were clearer than theirs.

His technique was actually pretty simple:

Step 1: Choose a concept you want to understand

Step 2: Explain it as if you're teaching it to a child

Step 3: Identify gaps in your explanation

Step 4: Review the material to fill those gaps

Step 5: Simplify and use analogies

That's it. Sounds simple, right?

It is simple. But it's not easy.

Because when you actually try to explain something simply, you immediately discover where your understanding falls apart.

Research on the "explanation effect" shows that people who can explain concepts clearly have deeper understanding and better retention than those who cannot, even if they performed equally well on tests.

Let's break down each step in detail.

Step 1: Choose a Concept (And Be Specific)

Don't try to understand "biology" or "calculus." That's too broad.

Pick one specific concept:

• Mitosis

• Derivatives

• Supply and demand

• Photosynthesis

• Recursion in programming

• The causes of World War I

The more specific, the better. You want something you can fully explain in 5-10 minutes.

Why this matters:

Vague goals create vague understanding. When you pick something specific, you know exactly what you need to be able to explain.

If you're studying for a test, break the material into 10-15 specific concepts. Master one concept per day using the Feynman Technique rather than trying to "understand everything" all at once.

Step 2: Explain It Like You're Teaching a Child

This is where it gets real.

Open a blank document or get a piece of paper. Now write out an explanation of your concept as if you're teaching it to a 12-year-old who's smart but knows nothing about the subject.

The rules:

1. No jargon If you use technical terms, you must immediately explain them in simple language.

Bad: "Mitosis is the process of nuclear division."

Good: "Mitosis is when one cell copies all its parts and splits into two identical cells. It's like photocopying yourself."

2. Use everyday language Write like you talk. If you wouldn't say it out loud, don't write it.

3. Use analogies and examples Connect new concepts to things your "student" already understands.

4. Assume nothing Don't skip steps because they seem obvious. The child doesn't know what you know.

Why this works:

Using simple language forces you to actually understand what you're talking about. You can't hide behind technical terms or hand-wave past confusing parts.

Research on "cognitive load" shows that when you translate complex ideas into simple language, you're actually processing the information more deeply because you have to understand the relationships between concepts, not just the terminology.

Actually write this out or record yourself saying it. Don't just think it in your head… you need to externalize it to see where your explanation breaks down.

Step 3: Identify Gaps (The Uncomfortable Part)

This is where the Feynman Technique gets uncomfortable… and valuable.

As you try to explain, you'll hit moments where you realize:

• "Wait, I don't actually know why this happens"

• "Hmm, I can't explain how we get from this step to that step"

• "I'm using this term but I can't define it simply"

• "I skipped something important because I don't actually understand it"

These gaps are gold.

They're showing you exactly where your understanding is weak. Most people never discover these gaps because they never try to explain… they just nod along during lectures and hope the test doesn't expose their confusion.

Common gaps:

The "because that's just how it is" gap: You can state the rule but not explain why it exists.

Example: "You flip the fraction when dividing fractions because... that's just the rule?"

The "then magic happens" gap: You understand the beginning and end but not the middle.

Example: "You plant a seed, and then... somehow... it becomes a tree?"

The "I'm using words I don't understand" gap: You're repeating terminology without grasping what it means.

Example: "The mitochondria is the powerhouse of the cell" (but what does "powerhouse" actually mean in this context?).

What to do with gaps:

1. Highlight them in your explanation

2. Don't feel bad… finding gaps means the technique is working

3. Write down specific questions you need to answer

4. Go back to the source material with targeted questions

The goal isn't to write a perfect explanation on the first try. The goal is to expose what you don't understand so you can fix it. Every gap you find is progress.

Step 4: Review and Fill the Gaps

Now go back to your textbook, lecture notes, or source material. But you're not re-reading everything… you're targeting specific gaps.

This is way more efficient than generic "review." You know exactly what you're looking for.

The targeted review process:

1. Write your specific question: "Why do you flip the fraction when dividing?"

2. Find the answer in your materials: Look specifically for that explanation

3. Understand it: Don't just read it… make sure you actually get it

4. Add it to your explanation: Revise your simple explanation to include this new understanding

5. Try explaining again: Does it make sense now?

Research on "retrieval practice" shows that actively seeking specific information is far more effective for learning than passive re-reading.

Example of filling a gap:

Gap identified: "I don't know why you flip the fraction when dividing."

Targeted research: Ah, dividing by a fraction is the same as multiplying by its reciprocal. And that's because division asks "how many of this fit into that?" So 2 ÷ (1/2) means "how many halves fit into 2?" That's 4. Which is the same as 2 × 2.

Revised explanation: "When you divide by a fraction, you flip it and multiply. This works because division is asking 'how many of these fit into that?' If I have 2 pizzas and I'm dividing by half-pizzas, I'm asking how many halves are in 2 whole pizzas… which is 4. That's the same as 2 × 2."

See how much better that is than just memorizing "flip and multiply"?

Keep a "gap list" for complex topics. As you study, write down every "wait, why?" moment. These become your targeted review questions.

Step 5: Simplify and Use Analogies

Now that you've filled your gaps, rewrite your explanation to make it even clearer.

The simplification process:

1. Remove unnecessary complexity Cut any words or concepts that aren't essential to understanding the core idea.

2. Create analogies Compare the concept to something familiar.

3. Use concrete examples Abstract concepts become clear with real-world instances.

4. Tell a story Narrative structure makes information memorable.

Great analogies make complex ideas instantly clear:

DNA replication: "Imagine unzipping a zipper. Each side of the zipper becomes a template for making a new matching side. Now you have two complete zippers, identical to the original."

Compound interest: "It's like a snowball rolling down a hill. It starts small, but it picks up more snow as it rolls. The bigger it gets, the faster it grows."

Neural networks: "Imagine teaching a child to recognize dogs. You show them pictures and say 'dog' or 'not dog.' After seeing hundreds of examples, they learn the pattern. Neural networks learn the same way, by adjusting their 'recognition' based on feedback."

Why analogies work:

Research on "analogical reasoning" shows that we understand new concepts by mapping them onto things we already understand. Good analogies create instant comprehension.

If you can't think of a good analogy, that's a sign you don't fully understand the concept yet. Keep working on it until you can say "It's like..." and have it actually make sense.

The Feynman Technique in Action: A Real Example

Let me show you this technique with a concept I struggled with: What is a derivative in calculus?

First attempt (exposing my ignorance):

"A derivative is... the slope of a curve at a point? It's like... how fast something is changing? You calculate it by... doing some math with limits? And there's a formula... f'(x) = something?"

Gaps identified:

• What does "slope at a point" actually mean?

• Why do we care about how fast something changes?

• What are limits and why do we need them?

• How do you actually calculate a derivative?

After targeted review, simplified explanation:

"Imagine you're driving and you look at your speedometer. It says 60 mph. But that's weird… you're not traveling for an hour, you're just at one moment in time. So what does '60 mph' mean at a single instant?

It means that if you kept going at your current rate, you'd travel 60 miles in an hour. Your speedometer is showing how fast your position is changing right now.

That's what a derivative is. It's the 'speedometer' for any changing quantity. It tells you the rate of change at a specific moment.

If you're graphing your car's position over time, the derivative at any point is the slope of the graph at that exact spot… how steep the line is, which tells you how fast you're going.

We calculate it using limits because we want the slope at one exact point, not between two points. We imagine the two points getting closer and closer together until they're basically the same point, and the slope at that limit is the derivative."

See the difference? The second version actually explains what it is and why it matters using an analogy anyone can understand.

After creating your simplified explanation, try it on someone who doesn't know the subject. Their confused looks will tell you exactly where you need to clarify further.

Why the Feynman Technique Is So Powerful for Learning

This isn't just a nice exercise. The Feynman Technique leverages multiple learning principles simultaneously:

1. Active recall You're pulling information from memory, which strengthens retrieval pathways.

2. Elaboration You're creating connections and context around the information.

3. Metacognition You're thinking about your thinking, which reveals gaps.

4. Teaching effect Preparing to teach activates deeper processing than just studying for yourself.

5. Simplification forces understanding You can't simplify what you don't understand.

Research shows that students who use elaborative rehearsal and self-explanation significantly outperform those who use simple repetition.

And here's the best part: once you truly understand something using this technique, you rarely forget it.

Because you didn't just memorize… you built a mental model. You understand the why and the how. That kind of knowledge is durable.

How to Use the Feynman Technique for Different Subjects

The technique is universal, but here's how to adapt it for different types of learning:

For Math and Science:

Focus on: Why formulas work, not just how to use them

Example approach:

• "Why does the Pythagorean theorem work?"

• "What is actually happening when we balance a chemical equation?"

• "Why do we use this formula for this type of problem?"

Explain: The underlying logic, not just the procedure

For History and Social Sciences:

Focus on: Causes, effects, and connections

Example approach:

• "Why did this event lead to that event?"

• "What were people thinking and why?"

• "How do these different factors connect?"

Explain: The narrative and causation, not just dates and facts

For Languages:

Focus on: Grammar rules and why they exist

Example approach:

• "Why does this language have gendered nouns?"

• "What's the logic behind this verb conjugation pattern?"

• "How does this grammatical structure actually change meaning?"

Explain: The patterns and logic, not just memorized vocabulary

For Programming:

Focus on: What the code is actually doing

Example approach:

• "What happens step-by-step when this function runs?"

• "Why does this algorithm work?"

• "What problem is this design pattern solving?"

Explain: The logic and flow, not just syntax

The Feynman Technique works for literally any subject because it's not about the content… it's about forcing yourself to understand rather than memorize.

The "Rubber Duck" Method: Feynman for Programmers

Programmers have their own version of the Feynman Technique called "rubber duck debugging."

The idea: when you're stuck on a problem, explain your code line-by-line to a rubber duck (or any inanimate object).

Why it works:

The act of explaining forces you to slow down and articulate what each part is supposed to do. Usually, you spot your error within minutes just by talking through it.

This is the Feynman Technique in disguise. Explaining reveals gaps.

You can use this for any subject:

Stuck on a problem? Explain your approach to a stuffed animal, a plant, or an empty chair.

"Okay, Mr. Cactus, here's why I think the answer is X..."

As you explain, you'll either:

1. Realize your logic is sound (confidence boost)

2. Spot the flaw in your reasoning (exactly what you needed)

Keep something on your desk specifically for explaining to. It sounds ridiculous. It works ridiculously well.

Common Mistakes When Using the Feynman Technique

Mistake #1: Using complex language

If your explanation includes terms like "furthermore," "wherein," "vis-à-vis," or heavy jargon, you're not simplifying… you're performing.

Write like you talk. Use short sentences. Be conversational.

Mistake #2: Skipping the writing step

Thinking through an explanation in your head is not the same as writing it out. Your brain lies to you about what you understand. Writing exposes the truth.

Mistake #3: Not actually finding gaps

If you did the technique and didn't find any gaps in your understanding, you probably weren't being honest enough about what you don't know. Try again, more critically.

Mistake #4: Giving up when it's hard

The technique is supposed to be uncomfortable. That discomfort means you're learning. If it feels easy, you're either already an expert or not going deep enough.

Mistake #5: Not testing your explanation

Create your explanation, then wait a day. Can you still explain it? That's the real test. Understanding should be durable.

The technique should feel slightly frustrating at first. You'll be confronted with how much you don't actually understand. That's not failure… that's the entire point.

The "Teach to Learn" Principle

The Feynman Technique is built on a fundamental truth: teaching is the ultimate learning.

Research consistently shows that people preparing to teach material learn it more deeply than those studying for themselves.

Why? Because teaching requires:

• Complete understanding (you can't fake it)

• Organization (you have to present it logically)

• Anticipating questions (you have to think through potential confusion)

• Simplification (you have to make it accessible)

Every one of these cognitive processes strengthens your own understanding.

You don't need an actual student to benefit:

Just the intention to teach activates these processes. When you study "to teach," you automatically process more deeply than when you study "to remember."

The practical application:

Instead of thinking "I need to learn this for the test," think "I need to learn this well enough to teach it."

That subtle reframe changes your entire approach. You stop asking "What will be on the test?" and start asking "Do I understand this completely?"

Form a study group where you take turns teaching concepts to each other. It's the most efficient study method there is because everyone learns through both teaching and being taught.

The Ultimate Test: Can You Teach It?

Here's your challenge:

Pick something you "learned" recently. Now try to teach it to someone who knows nothing about it… a friend, family member, or even a stranger.

If they understand it, you understand it.

If they're confused, you don't.

This is brutal honesty. But it's also the fastest path to real understanding.

I tried this with photosynthesis after embarrassing myself with my cousin. I studied it using the Feynman Technique. Then I explained it again.

"Plants are like little solar panel factories. They capture sunlight using chlorophyll (which makes them green) and use that energy to combine water from their roots and carbon dioxide from the air to make glucose, which is basically plant food, sugar they can use for energy. As a bonus, this process releases oxygen, which is lucky for us because we breathe oxygen. So basically, plants are turning sunlight, air, and water into food and breathable air."

My cousin: "Oh! So they're like making their food from scratch using sunlight as power?"

Me: "Exactly."

That's understanding. Finally.

Final Thoughts (Simplified)

Here's what the Feynman Technique taught me:

I didn't know nearly as much as I thought I did.

And that's actually great news. Because once you know what you don't understand, you can fix it.

Most people go through their entire education thinking they understand things they've only memorized. They can pass tests but can't explain concepts. They collect information but not knowledge.

The Feynman Technique is uncomfortable because it exposes this gap. But it's also liberating because it gives you a clear path to real understanding.

Stop memorizing. Start explaining.

When you can teach it simply, you've learned it deeply.

To Recap:

• Memorization ≠ understanding = repeating words isn't learning

• Feynman Technique = 4 steps = choose concept, explain simply, find gaps, review, simplify

• Explain like teaching a child = no jargon, simple language, analogies

• Gaps are valuable = they show exactly what you don't understand

• Targeted review is efficient = fix specific gaps, don't re-read everything

• Analogies create clarity = connect new concepts to familiar ideas

• Teaching forces deep learning = preparing to teach makes you learn better

• Test by actually teaching = if others understand you, you understand it

• Works for any subject = universal technique for deep comprehension

• Write it out = thinking it isn't enough, externalize to expose gaps

Here's to actually understanding instead of just pretending to.

Your future self (and anyone you try to explain things to) will thank you.

Ray