1. Introduction
If I say that I first saw the lightning and then heard the thunder, this statement is logical. If I were to say that I heard thunder and then saw lightning, it would be illogical. So what's the logic? The theory in the logic textbook is of course logic, but we are talking about much more than that. The following will discuss the true meaning and value of logic, analyze the nature of formal logic, and then compare the difference between formal logic and dialectical logic.
2. What Is Logic
2.1 Definition of Logic
Our brains are in constant motion, in addition to receiving sensory experience, they are also constantly thinking. Thinking is to make new products of thought from existing products of thought. Thought includes perceptual thinking and rational thinking. Perceptual thinking is thinking without rules, rational thinking is thinking with rules, also called reasoning. Logic is the rule of reasoning. When thinking is expressed in language, logic becomes the rule of language. The rules of words and single sentence are called grammar, and the rules of relations between sentences are called logic.
Definition: Logic is the rational rule of relations between statements.
Logic is not the law of objective things. Logic appeared after the emergence of human rational thinking, there is no logic before the emergence of rational thinking. If logos means objective laws, then logos is quite different from logic. For example, the relationship between force and acceleration is an objective law that has existed since the Big Bang, but there was no logic then.
Objective laws need to be expressed in language, so many philosophers call objective laws logic, which is completely wrong. Each discipline studies different laws, and logic applies to all disciplines because all disciplines use rational thought and language. When language is used to reflect reality, language is a simulation of reality. Simulation is to imitate a real thing with a fake thing. Some of the structures and properties of the fake thing should be the same as those of being imitated, so some rules must be laid down for the use of language, and this is how logical rules arise.