Part 1 of GCT logic-Logical Reasoning

I took the gcttest immediately. I did some questions two days ago and checked out that I was very poor at the "logic". Therefore, this was the key.

Logic can be divided into "Logical Reasoning", "argument Reasoning", and "analytical reasoning" from simplicity to complexity ". This article briefly introduces "Logical Reasoning" from a macro perspective ".

I. As the basis, I will introduce several concepts first.

Logic:It mainly studies the correctness or effectiveness of reasoning in terms of form or structure.

Reasoning:Refers to the thinking process of introducing new knowledge to draw conclusions based on known knowledge.

Proposition:It is the description and Expression of objective facts. The basic nature of a proposition fundamentally determines the nature of reasoning. The premise and conclusion of reasoning are propositions.

Proposition reasoning:It can be determined as long as the simple proposition included in the analysis is an atomic proposition.

For example:

If a is the victim, a has time to commit the crime.

Change expression:

No time for committing crimes

A is not the operator

If the lowercase letters "P" and "Q" are used to indicate "A is the operator" and "A has time for committing crimes", the general structure of reasoning is as follows:

If P, then q

Non
P

Non-Q

Among them, "If ...... So ......" , "Non" is a logical constant, "P", "Q" is a variable, also known as a proposition variable.

Word term reasoning:It is necessary to analyze a simple proposition, that is, the concepts contained in an atomic proposition, that is, word items, to determine.

For example:

All lies are untrusted.

Some lies are untrusted.

If the capital letter "S" is used to represent "lie" and the capital letter "P" is used to represent "untrusted", the general structure of the above reasoning is:

AllSYesPOf

Some s are P

Among them, "All ...... Yes ......" , "Some ...... Yes ......" It is a logical term. "S" and "p" are variable items, which are also called word item change items.

2. The content of this part is first shown in the figure

3. Give a general description of this part through the diagram for macro understanding.

1. Formal Reasoning

• Propositional Reasoning

The Proposition Logic analyzes a compound proposition to its simple proposition to determine the correctness of a reasoning. A more complex composite proposition can be constructed on the basis of the Basic composite proposition, and a more complex proposition reasoning can be performed on the basis of the Basic composite reasoning.

• Word term reasoning

The word term logic needs to further analyze the internal structure of a simple proposition, that is, the relationship between concepts. Based on the true and false nature of a declarative proposition, not only can direct reasoning of the current relation be performed, but also deformation reasoning and three-field reasoning of the declarative proposition can be performed.

• Induction and Analogy

This part is about the scientific understanding and the inductive and analogy reasoning that plays a wide role in the common thinking.

• Causal relationship

This section describes the logic method for finding a causal relationship.

• Relational reasoning and modal Reasoning

Objective things are not only of a certain nature, but also in a certain relationship. The proposition that reflects the relationship between things is a relational proposition. According to the basic nature of the relationship, relational reasoning can be performed. When analyzing the true and false nature of a proposition, if you need to further consider the modal, you can obtain the modal proposition for modal reasoning.

2. Non-formal reasoning

The above content considers the correctness or validity of reasoning in terms of form or structure. However, there are still some problems that are difficult to consider clearly in terms of form or structure. This section describes non-formal theories, including definition theory, division theory, basic laws of logic, argument theory, and fallacy theory. They mainly determine the correctness or effectiveness of reasoning or arguments by proposing some important rules and requirements.