01 - Why You Need Science



As a human being, living in the modern world, you are fed ideas constantly. 

What you need to succeed in  this world is a set of mental tools to be able to test ideas for REALITY.
Is this idea true or false?

Knowing what is true and what is false can determine your quality of life, your mental health, your financial status, and even your very survival. Making the wrong choices based on bad information can lead to serious life problems.

Sorting out the truth has been a problem for humans for a very long time. People say untrue things around us constantly, in advertisements, in conversations, in books, on TV, in social media. They might not be purposely lying to you, they might just be repeating what they heard from someone else, what they believe to be true. They might have a very specific agenda for wanting you to believe something, or none at all. Lies can and do come from any person, businesses, and even from your close friends and family.

If you can’t always trust what you’re told, then what? Should you just swear off humanity forever and live in a mountaintop cave like a hermit? Maybe a tiny house in the country with only dogs or cats for company?

Tempting, but most of us have to live and work and eat and interact and survive in this world we’re in. The good news is, thinking is a skill that you can work on and practice, just like anything else. You can *always* improve your thinking skills. We can train our brains to tell the difference between truth/reality and fantasy/falsehood by asking good questions.

Thinking skills are sometimes taught in school as critical thinking. Critical thinking just means that when you are presented with an idea, you ask questions and put it through some tests in your mind before you decide to believe that idea. That's it. In the absence of critical thinking, people don't ask questions. They just believe what they are told to believe.

These tests have basic rules. These rules for testing ideas aren’t something that I made up, I can't take any credit for them. Humans have been trying to improve their thinking and sort out truth from lies for thousands of years, it’s nothing new. People who specialize in thinking about thinking are called philosophers.

Socrates was a philosopher from around 2000 years ago whose main focus was on how to live a good and virtuous life, despite the corruption all around him. So why was Socrates so famous, and why is he still so famous?

Socrates figured out that you can't always depend upon those in authority to have sound knowledge and insight. People may be in positions of power and yet be deeply confused and irrational, abuse their power, lead others astray, and he recognized this. Socrates called out public figures in his time for being irrational, making unreasonable assumptions about things, and saying one thing but doing another. Now not *every* public figure is irrational. It’s your job to figure out who you can and can’t trust, based on evidence.

Socrates said it's important to ask questions, seek *reliable* evidence, and do detective work on an idea before you decide to believe it, or before you decide to trust the person asking you to believe the idea.

You should also question your *own* thinking from time to time too, because irrational ideas can creep in and take root anywhere. The same scrutiny you apply to the ideas of others should be regularly applied to your own. Check in: are you still making decisions based on reliable evidence, or are you letting yourself be swayed by feelings or manipulative tactics?

By applying some simple rules, you can avoid being tricked, and avoid the harm that believing lies can do to you... financially, physically, emotionally, and socially.

So here we go, here are:

Ten Rules for Thinking Like a Scientist

Rule #1: Ask for evidence

Asking for evidence doesn’t have to be complicated. Let's walk through an example.

A friend might tell you,

Frogs live in that pond!

You have some basic scientific knowledge already, and you know that frogs do exist, frogs aren't imaginary creatures. What your friend is saying is indeed possible,more on this in Rule 3, so being logically possible is a good start.

You then say,

Okay. Show me the evidence.

and the friend shows you the actual frog they caught there, or you find a froggy footprint in the mud near the pond. A footprint isn't foolproof, but it's pretty good evidence that there are frogs in that pond.

Now let’s say your friend says instead,

A dragon lives in that pond!

You have some scientific knowledge that dragons don't actually exist and are imaginary. Or, you're not sure if they really exist or not, that's okay. Hey, it's okay to not know everything. You can still use scientific thinking, even if you don’t have a good background of knowledge yet. You respond the same way,

Show me the evidence.

Your friend says,

Jack told me.

This is not evidence, it doesn't prove anything. This is called "hearsay". The most you can do is to go to Jack and ask him for evidence.

What would good evidence look like? Evidence might be dragon scales, finding scorched bushes at the side of the pond from fiery breath, or maybe dragon footprints.

But did your friend see any of these? If so, could they be explained by something else? Could the scorched bush be from a campfire? Could the dragon scales be clam shells? Is there just one form of evidence, or more than one? The more forms of evidence, the better.

If there isn't any evidence at all, it doesn't mean that the thing is definitely false. But you don't need to believe it, either. It is simply unproven. You can put it on the undecided pile in your mind. This is the best place for it.

If you hear something that is important to your health or well-being, or that affects a big decision that you need to make, you should not just ask for evidence, but fact check that evidence. Fact-checking is always a good idea. Here's how to fact check like an expert, and yes, this takes some work, but even if you don't do all of these steps, doing some of them will help you figure out if the evidence given to you is reliable or not.

Someone who is telling the truth should have evidence to back up their claims, and not be offended when you ask questions. Getting offended and becoming angry when asked for evidence is a distraction technique [see Rule 2] and a big red flag.

Rule 2: Saying it with drama doesn’t make it true

How often do you hear people start a story with an assumption like this:

  • Oh, yeah, it's totally a fact. Carrots improve your eyesight.
  • It's 100% true that carrots improve your eyesight, everyone knows that.
  • All the smartest people know that carrots improve your eyesight.

Or the reverse.

  • Only an idiot would think that carrots improve your eyesight.

They want you to believe that everyone thinks a certain way, and that you are outnumbered and/or stupid if you don’t agree.

Convincing speakers put a lot of energy and drama into what they are saying. This encourages listeners to believe them. People assume that if something is said with a lot of feelings or repeated over and over again, it must be true.

But being convincing is not the same as being truthful. You can only judge truthfulness by looking at the evidence.

When you want to understand if something is true or not, listen to *what* people say, not just how they say it. Don’t be bullied into believing something is true just because someone says it loudly or proclaims that “everyone” knows that to be fact, or gets offended and angry.

Try to imagine the person saying the same thing very calmly. Do you actually like what they are saying, or just how they say it? Even if you like what the person is saying and it makes sense to you at the time, you should still ask for evidence and some kind of verifiable facts.

Just repeating something over and over can indeed make people believe it to be true. In fancy language, this is called the "illusory truth effect" and it's how fake news works.

Carrots improving your eyesight is something that most people believe just because they keep hearing it over and over again. Not based on actual evidence.

Here are some other things that have been repeated so often everyone assumes they're true.

  • You only use 10 percent of your brain.
  • Vitamin C cures the common cold.
  • Crime in the United States is at an all-time high.

Do you believe some of these too? And yet the evidence doesn’t support any of them. The word ending oid means has the shape of so a factoid is something that has the shape of a fact but isn't a fact.

If you hear a factoid from one person, it might sound ridiculous and unbelievable at first. But after five people say it, you are likely to accept it as true. This is just how our human brains work. It's kind of a weird glitch.

But...once you know how this technique works, it doesn't hold so much power over you. If you hear something repeated several times in different places, use your thinking skills and fact-check before you decide to believe an idea. Knowledge, and asking for evidence, gives you the power to not be fooled.

Rule 3 :There is a rational explanation for everything

This rule will save you so much time, worry and irrational fear, if you decide to use it.

Up until the early 1800s, most people thought that disease was caused by evil spirits. If you were sick, it must be because a bad spirit was doing you harm, or someone placed a curse on you. We didn’t yet know that bacteria and viruses caused infectious disease. We didn’t understand much about the human body at all.

The word rational means logical reasoned intelligent showing good judgment, shrewd.

Once we started looking for a rational explanation for diseases we began to make real progress in finding out the truth about them. If this disease wasn't from an evil spirit, and wasn't from a supernatural force, then what real factor could be causing it? What do we know already? What evidence can we find to make some guesses and then either prove or disprove them?

We will never understand the causes of all things that happen in the world. But just because you don’t understand why something happens, you shouldn’t automatically assume it was caused by supernatural forces. Assume that there is a perfectly good rational reason for why that thing happened, and then investigate and look for evidence.

Did you hear a noise in the other room?
What are some rational reasons for a noise in the other room?
  • The wind blew through an open window and knocked something over.
  • A cat knocked something over.
  • A picture on the wall was held by a loose nail that finally gave out.
  • Someone else is in that room.
What are some irrational reasons for a noise in the other room:
  • Ghosts
  • Devils or angels
  • Spirits
  • Curses, magic, or other supernatural factors.
When you go in the other room to see what happened, first of all, assume a rational explanation. Some real thing caused that noise. What is the evidence? Is the window open on a windy day? Is there a cat in the room? Did your family member come home unexpectedly? Do you see the plaster in the wall weakened around the nail hole, like maybe it gave way?

Don’t let your mind automatically jump to supernatural conclusions about things. Try to put aside the fears that might arise spontaneously, and ook at the situation with your thinking, evidence-requiring mind. We learn important things about the world when we assume there is a rational, real-life cause and then investigate it. Believing in supernatural causes doesn’t increase our understanding of the world, so et’s not waste any mental energy on them.

"But...I'm sure that ghosts exist! Or that dowsers can find water! Or that psychics can know secret things about me!"

A man named James Randi, who is a skeptic, someone who asks questions and looks for evidence before believing, offered a million dollar cash prize to anyone who could have their paranormal powers proven true. This prize was offered from 1964-2015, and over a thousand claimants were tested with simple scientific tests to see if there was any evidence for their claims. No one ever successfully passed the test. Every paranormal claim was proven false.

By assuming a rational explanation for everything, you can prevent a lot of pointless fright and drama in your life worrying about supernatural creatures. Without the distractions of ghosts and monsters, you might actually discover the true cause!

Rule #4: Connection isn’t always cause.

Every event has a rational explanation, as we learned in Rule 2. But we also want to look at the evidence carefully and keep this rule in mind. When two events occur, one right after another, someone will *always* think, the first event caused the second event. It’s very tempting to believe it, and people definitely do.

If one thing A happens and then another thing B happens, there are all kinds of possible explanations.

  • A causes B [direct causation];
  • B causes A [reverse causation];
  • A and B have a common cause, but do not cause each other;
  • A and B both cause C, something else;
  • A causes B and B causes A, the causes go in a circle;
  • A causes C which causes B, the cause is indirect;
  • There is no connection between A and B; and what happened is a random coincidence
Seven possible explanations, not just one! You have to look at the evidence to see what explanation it supports, and what you can rule out.

Let’s suppose that someone rang the doorbell and then suddenly all the lights went out.

"Ringing the doorbell must have made the lights go out!"
If we look more carefully, we'd see that it’s just a coincidence. The real cause was a car down the street crashing into a power pole that supplied electricity to the house.

Or maybe you investigate and find that there *is* a connection. Maybe an electrical short occurred in the doorbell and then affected the electricity throughout the house. But only further checking and possibly getting an expert opinion can determine the true cause.

What we don’t want to do is just decide
"Well, the doorbell must have caused the power outage."
without any evidence. It’s better to admit,
"I’m not sure if there is a connection. There isn't any evidence for it except for the doorbell and the power going out happening close together in time."
In Europe in the Middle Ages, people often had the idea that body lice were healthy to have. Why? Well, body lice are very sensitive to temperature, so if a person gets a fever and their temperature rises, body lice will often leave and go find another host.

But people in the Middle Ages didn’t have thermometers. They couldn’t take temperatures. They could only sense big increases in body temperature. But they knew if a person was sick, and they knew when a person had body lice. They saw

A] body lice leaving,

B] a person getting sick.

but the reality was:

B] a person got sick and had a fever, which caused

A] body lice leaving

Rule #5: Natural laws are unbreakable

Natural laws are rules about how things work in the world. They are rules that we have observed over and over again throughout time, without any exceptions.

Natural laws tell us how things behave. For example, if you drop a rock, it will always fall to earth. Not sideways or upwards, either, unless a strong wind pushes it hard enough. Things fall down towards the center of the earth, every time, unless there is something holding them up. Every single time you pick up a rock and drop it, it will fall down, in the same direction. This is the Law of Gravity. It doesn’t ever NOT happen. You can go test it yourself.

Gravity is a basic force that happens between everything in the universe. We can predict exactly what will happen in certain situations because we know about gravity. We can calculate its exact force with math, and get the right answer every time. There is overwhelming evidence for these natural laws. They have been tested and tested and tested again, thousands of times, with the same result.

Science teaches you about natural laws, and this is why basic science education is really important for everyone. Once you know more about what these laws are, you will have a powerful mental tool for truth-finding and scambusting. You will know right away that certain things simply can't be true.

How does this help us tell the difference between reality and fantasy? Well, often people want us to believe in things that break the natural laws.

One important law is the Law of Conservation of Energy: energy is never created or destroyed. All the energy that is here now has always been here, it just changes form. The chemical energy in the sun is converted to heat and light energy. The heat and light travel through space to Earth, where the heat energy warms the Earth and the light energy is stored as chemical energy by plants, in the form of sugars. We eat the sugar energy in the plants and we turn that into heat energy and motion energy and store it as chemical energy again in our fat.

Eventually ALL energy ends up as heat. Once it’s heat, it can’t change to anything else, it just radiates around the universe . We’ll discuss in later lessons .

So if you know this basic fact that energy is always conserved and can’t be created or destroyed, just converted, and you have thought about it and understood it properly, no one can ever fool you into believing that they have invented a machine that breaks the natural laws and does something impossible.

You can invent a machine that is very efficient at converting energy. But you cannot invent a machine that does something without *any* energy input or fuel for example, the flying brooms in Harry Potter. For them to fly in the air and carry a student, they’d need a lot of energy! Never mind that they don’t have any kind of wing structure, you’d need a lot of energy to power a flying machine with such agility and speed. Imagine if you had to power it with batteries, how many you would need!

The broomsticks in Harry Potter don’t have battery compartments or gas tanks. The energy is just...magical. That’s fun to believe in a fictional story like Harry Potter, but stories are the only places where the natural laws don’t apply. Keep that in mind when someone wants to make you believe in something that sounds too good to be true...would it have to break any of the natural laws in order to work? Then we know that something must be fishy.

Rule #6: An idea isn’t automatically right just because you can’t think of any alternatives.

Algebra is really difficult for some people to grasp, like me! But just because I don’t understand all the complexities of advanced algebra, that doesn’t mean that algebra doesn’t exist. I’m just not an expert at it. I wouldn’t try to make a decision about whether or not a math statement was true without consulting a few experts who could be better judges of the evidence.

So for example...

xc = bs/2

I don’t know, does it? I admit that I have no idea! It's totally okay to not know one is capable of it anyway.

But people believe that they know the answer to other complicated things all the time, on subjects that they don't really know much about. People don’t tell stories and give opinions about algebra very often, but they do discuss and have opinions about how the world began, how the pyramids were created, what different skin colors represent...and they often can’t imagine any other explanation being the right one but their own.

I’ve heard someone say that you shouldn’t take a shower after going out in the sun, because “it will wash the vitamin D right off you”. Well, Vitamin D creation starts in the deeper layers of your skin, underneath the top layer. It can’t be washed off. The top layer of your skin is just dead cells that protect you, like bark on a tree. And this is where having a library of science knowledge in your head is important, you become hard to fool!

When I explained this nicely, the other person was very offended. “That’s the way that I understand it to happen, I don’t see how else it could work,” referring to their idea of vitamin D being made on top of your skin by sunlight, and removable by showering.

But not being able to imagine or understand any other ideas isn’t good evidence for your idea being right. Your idea needs its own evidence to back it up. Do some research. As always, we go back to the evidence. What does it support?

Sometimes people fall in love with their own ideas, and refuse to consider other possibilities, or even look at new evidence that might disprove what they already believe.

“No thank you, no need to look at evidence, I’m satisfied with my story and not willing to change it, thank you!”
That’s a closed mind. Even if you are convinced of an idea’s truth, if compelling evidence arises that might support another explanation, it’s worth looking at.

Keeping your mind open to new evidence is a key part of scientific thinking. When we say open-minded, this is what it literally means. Not that you’d believe anything, but that you are open to changing your mind if there is new evidence that supports a different belief. This should be a goal for all of us, because we are always making new discoveries and getting new information. And as humans, we start really liking some ideas and becoming attached to them, even if they aren’t true. That’s a problem. You have to always be willing to examine an idea for evidence of its truth, and look at that evidence without consideration for whether or not you want it to be true. More on this in the next rule, which is...

Rule #7: Consider all of the data, not just some of it.

Let’s say you were out walking one day, and a squirrel attacked you and bit you. Now you can say a lot of accurate things about this.

“I hate squirrels!”
“Squirrels can be dangerous!”
“That squirrel might have rabies!”
Only a test would confirm that, but it’s certainly possible.

What can you NOT say about this from your experience?

“All squirrels are dangerous!”
“All squirrels love to bite ankles!”
You could say that you HATE all squirrels, but that’s a different thing from all squirrels being dangerous. Why?

Because you have ONE experience of being bitten by a squirrel. how many experiences do you have with squirrels who have NOT bitten you?

If you walk through that park every day and this is the first time in ten years that you have been bitten by a squirrel, you can’t ignore all the non-biting squirrels. Even though that one biting squirrel incident REALLY stands out in your mind, it’s just one piece of data. Don’t let freak events blow everything else you know out of your mind. Consider ALL of the information available before forming a belief, not just the information you like or agree with or that immediately comes to your mind.

“Confirmation bias” is a term for what happens when you get new information, but only pay attention to the information that reinforces your beliefs. The parts that don’t match up get discarded, or you decide not to believe them or discredit them *despite* reliable evidence. This is really, really common. Try to put your own biases aside. After all, if you believe in something that is actually false, that could be harmful or dangerous to you. It could put you at risk for all kinds of things. You need to make sure that the things that you believe in are true. So if you start to get convincing evidence that something you believe in is actually false, or there might be a different attention. Try to put your actual beliefs aside and review the evidence for what it supports or doesn’t support.

Rule #8: Numbers must add up.

Some ideas seem to make sense, but the numbers don’t add up. Some people might promise that they can run a full-sized car on a flashlight battery, or a glass of water. The car needs energy, and the glass of water or the flashlight battery will provide it, right? That doesn’t contradict the natural laws we talked about earlier.

But the numbers matter! If you look at how much energy is needed to power a car that can carry four people in it, you’ll find out that’s a fairly large amount of energy, much more than is stored in a flashlight battery or a glass of water. The numbers of this idea don’t add up. They don’t make sense. Those numbers are important and must be looked at and explained. If the numbers don’t add up, something fishy might be going on.

Rule #9: They attack the person when they can’t argue with the idea

You’re in a group and one person says,

“I have an idea! Let’s eat tacos every Tuesday.”
Another person says,

“What? You're a stupid idiot!”
You’ll see this one all over the internet and in real life and in political debates and maybe even among your friends and family ….it’s everywhere. It's a very effective way to shut down a conversation or discussion. Instead of sticking to talking about the idea, and what you like or don’t like about it, or why or why not it would work, the attacker makes a distraction by insulting the person who had the idea and hopes to shame them into silence.

Maybe the attacks aren’t as harsh as calling someone an idiot. Maybe it’s something like,

“Who would listen to a kid’s opinion? You’re too young to have a say in this, haha!”
and then they pinch you on the cheek. That is the same thing. The person responding attacks the speaker for being young, and doesn’t even discuss theidea of Taco Tuesday. We were talking about tacos, and now suddenly we’re talking about how the speaker is too young to have an opinion. This is a way to distract listeners from the idea and dismiss or ignore it.

Stick to the idea. Attacking the person, instead of the idea, is the sign of a poor thinker who doesn’t know what else to do, and doesn’t know how to have a discussion in a mature way.

“Oh yeah, well you’re stupid, so nyeah nyeah NYEAH! Who cares what you say anyway!”
This basically shows everyone that you lack thinking and speaking skills to debate ideas. Be better than that. Stick to the topic. Don’t get personal. Don’t attack the speaker. Don’t bring up their age, weight, intelligence, race, gender, or anything else, no matter how sassy you think that zinger is going to be. It’s bad form and bad thinking and creates bad feelings for everyone, instead of discussion and progressing towards a solution that everyone can agree with.

If people use this kind of attack on you when you bring up an idea, you can say something like,

"Hmmm yes interesting. Uh, do you have a response to my idea? Because if you can only respond with a personal attack on me,I'm not going to waste my time talking to you."
In fancier language, this kind of attack is called an ad hominem attack, which means “to the person” in Latin. It's a very old tactic used to silence thoughtful discussion. The ad hominem attack responds to the person, not the idea. You can also say something like snappy like,

“Wow, really? A tired old ad hominem argument? Is that all you’ve got?”

Rule #10: Your friend’s story is is not scientific evidence

Anecdotes are short stories that are told to make a certain point. Storytelling is a very powerful tool!

Anecdotes are told for several reasons:

  • To cheer someone up or make them feel better:
    A man invites a friend over for lunch, but he makes a mistake while cooking and the lunch is ruined. The man's friend tells him about a time that she was expecting her in-laws over for dinner and accidentally burned her recipe to a crisp, after which they ordered pizza.
  • To share memories, feelings and history:
    Elderly people reminisce about where they were when World War II ended, or your mom tells you the story of when you were born.
  • To caution others:
    An audience of students is listening to a talk about illegal drug use. The students are bored until a speaker comes in to tell them a frightening story of how he abused drugs, lost his job, lost his family, and ended up in jail.
  • To persuade or inspire:
    A tutor comes to help a student struggling in math. She utells the student how she used to hate math and struggle with it too, and how she overcame her problems. The formerly struggling tutor is now so good at math that she actually enjoys teaching it to others.
Now these are all wonderful and very effective reasons to tell stories. But using a story that a friend tells you as "evidence" that something is common, or will help cure a medical condition...that's a bad idea. That is called anecdotal evidence, and it's not the same as scientific evidence.

Anecdotal evidence is popularly used in advertising and marketing.

  • Nightclubs advertise that a celebrity partied there, even though that celebrity may have been paid to visit once and will never come there again.
  • Casinos and lotteries tell stories of people who won lots of money, though winning something is very rare, and losses are almost guaranteed.
  • Diet companies show photos of people who were obese and then lost dramatic amounts of weight after using their products. The people in the photos may be paid models, and may have actually achieved their weight loss with the help of a different method, the photos might be altered. The supplement might be worthless, or might actually be and harmful to your health.
  • Your friend tells you that she knows someone whose skin cancer was cured by a special black salve, or whose bad luck was cured by a charismatic healer, or whose aging skin now looks youthful and smooth, thanks to the use of an anti-aging cream.
We cannot generalize one person’s experience to the population at large. Other people may have had very different experiences. If we combine many experiences, say 1,000 stories instead of 1, then we might be able to make some generalizations and understand what's happening. But one experience really doesn't mean anything. It's one data point. We need many data points from as many different people as possible to see a pattern. For a product, do 1 in 5 people see results? 1 in 50? 1 in 100? 1 in a million? And under what conditions? How do they compare to people who are using different products? Or under different conditions? Are there any negative effects to the product that might outweigh the benefits? This is what routine scientific testing looks for and tries to uncover.

Listen to your friend's story, as a friend, but then do your own research with reliable sources of scientific evidence. Look for objective testing with many data points under a range of different conditions before you decide to invest money, time or effort. I mean, if all we're talking about is a cute sweater, go for it. But a medical treatment, a diet, a financial investment, your vote in an smart and do some fact-checking before you decide to believe what someone tells you.

What’s Next: build your knowledge library

OK! So those are some rules for you to consider when you are presented with new information. They will help you to think about the quality of your thinking, and make your thinking better over time. And they will help you filter out lies from truth, so you won’t have lies taking up valuable space in your brain, and energy in your life.

Now that we have started to improve our thinking, and we understand the basics of how to think scientifically, we can start building scientific knowledge.

Scientific knowledge is like a library or toolset in your head that you can call on with your new truth-checking process. If you know what the natural scientific laws are, for example, and someone is trying to get you to believe in an invention that would break one or more, you can’t be fooled into believing in it. Scam artists rely on their targets being poorly educated in science and not understanding when they are being lied to.

We will start building your knowledge library, so that you’ll have a solid understanding of how the world works, even up to the universe level. We’ll go over the most practical aspects of chemistry, biology, physics, the human body, electronics...basically, the essentials of what you really need to know.

This education should never really end, of course. Learning should be lifelong. But if you go through these lessons with me, by the end of the course you will have a very strong foundation of science knowledge to draw from and use in your daily life, and also to help you reach your future goals. A quality science education pays off both now AND later.

The next lesson that I’ll have for you will be about Organizing Things into Categories. After learning how to think scientifically and do truth checks, this is the next most basic and important thing in science. We classify animals and plants and fungi and bacteria and rocks and pretty much everything that exists in some sort of category. It helps us figure out how things work, and see relationships and patterns more clearly.

Organizing Things into Categories is also extremely useful when your living space is a mess and you want to learn how to make it easier to live in, and keep it clean. Or if you are building a factory or even doing a cooking assembly line in a restaurant So we’ll talk about the scientific aspects of organization, and the practical aspects of organization, that you can apply to your life.

Coming next:  Lesson 02 - Get Organized


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