“Logic, the pillar of thought, must be strong.
“Your reading, speaking, and writing skills will also become stronger.”
Leaving with Eun-kyung Lee, mentor to 300,000 parents
The world's most exciting logic adventure

Teacher Eun-kyung Lee, who has been working as an elementary school teacher for 15 years, has written over 70 books and shares information about elementary school studies, school life, and parenting growth through various lectures and YouTube, and is called a mentor to 300,000 parents.
Having met and interacted with countless parents for 20 years, the question she hears most often is, “How can I raise a smart and creative child?”
And after much deliberation, I discovered that logic has the power to strengthen children's thinking and develop vocabulary, literacy, and creativity.

"The Forest of Logic" is the fourth installment of the "Forest Series" (Forest of Philosophy, Forest of Classics, Forest of Mythology), which has been the overwhelming number one youth series for three consecutive years. It is packed with 34 stories that deepen and solidify the roots of thinking, including stories from "Aesop's Fables" that children can easily relate to.
As children enjoy exploring the five branches of logic—judgment to distinguish right from wrong, laws to learn the rules of thinking, reasoning to solve complex problems by discovering small clues, errors to avoid traps in thinking, and appeals to effectively convey their thoughts—they will soon develop strong thinking muscles in their minds.


Logic is not a rigid and boring subject.
It is a solid foundation that helps you wisely solve numerous problems you encounter in everyday life.
If you properly establish logic, the pillar of your thinking, during your childhood, you will be able to grow into a wonderful adult who can wisely overcome any problem you encounter.

'Wolves hunt small animals.
I am a small animal.
So the wolf will try to hunt me!' The pig used inductive reasoning to anticipate the danger that was coming to him and immediately took action.
He took the initiative to change the situation, saying, 'If the wolf is going to hunt me, I have to move first!'
Next, the pig used hypothetical reasoning.
The pig, assuming that 'if the wolf is offered an attractive offer, he will follow it,' lured the wolf into a hole with a trap.
And the plan worked perfectly!
--- p.20

If you are confused about whether something is a proposition or not, look at an actual sentence example to make sure.
The sentence 'Whales are mammals' is a proposition.
Because you can tell exactly whether it is true or false.
Also, the sentence ‘King Sejong is a woman’ is also a proposition.
Because we can definitely determine that this is false.
On the other hand, the proposition 'This flower is the prettiest in the world' is not true.
Since each person feels differently about which flower is the prettiest, it is impossible to distinguish between truth and falsehood.

--- p.27

Absolute judgment ensures fairness because the desired outcome is achieved by meeting fixed criteria.
I can be evaluated solely on my efforts and achievements, without comparing myself to others.
On the other hand, relative judgment has the advantage of allowing me to clearly understand my position.
This is why relative evaluation is more appropriate in situations where rankings are important, such as college entrance exams or sports.
The reason Kim Yuna won the gold medal at the Vancouver Olympics was because absolute and relative evaluations were appropriately balanced.
Because we ranked players based on absolute evaluations of technical and artistic scores compared to other players.
--- p.84

The law of contradiction is a fundamental principle of logic that states that two contradictory statements cannot be true at the same time.
Simply put, it means that in a given situation, two opposite statements cannot be true at the same time.
For example, 'I am at home now' and 'I am not at home now' cannot be true at the same time.
The law of contradiction is an important tool that helps us avoid this confusion and organize our thoughts clearly.

--- pp.98-99

The syllogism is the royal road of logic systematized by the ancient Greek philosopher Aristotle.
It is no exaggeration to say that it is the tool that forms the basis of all conversation and persuasion.
The premise that 'all men are mortal' is a universal truth that no one can refute.
The minor premise, 'Socrates is human,' presents a specific case.
Finally, if we connect these two premises, we naturally arrive at the conclusion that 'Socrates is mortal.'
In this way, the syllogism creates a persuasive conclusion through a logical connection between the premises.

--- pp.144-145

In fact, we also frequently use contrastive reasoning in our daily lives.
For example, after visiting two tteokbokki restaurants, you compare the tastes and conclude, "This place's sauce is spicy and that place's is sweet!" Or, after taking a test, you realize, "I'm weak at descriptive questions after comparing the questions I got wrong with the ones I got right."
Contrastive reasoning like this is very helpful in determining what to do next.

--- p.194

We too often make this mistake of hasty generalization in our daily lives.
For example, think about when someone says this:
“There were two burglaries in our neighborhood last month.
“This neighborhood is completely dangerous.” Of course, there have been burglaries, but it’s unfair to brand the entire neighborhood a danger zone based on just two incidents.
This is also a common case.
“I came to this movie theater last time, and the staff was rude.
“The service here is terrible.” It’s also a flawed inference to generalize the attitude of all employees based on a single experience.

--- p.209