Riding the wind of rebirth

"Mozi? Isn't Mozi the patriarch of carpenters?" Li Laosan asked.

"Well, Mozi was indeed a master craftsman, but the one you're imagining is probably Lu Ban, the Gongshu Ban in ancient texts, who was once Mozi's adversary."

"We'll talk about these later. Let's start with logic. When proposing specific solutions to fallacies and sophistry, ancient thinkers couldn't help but consider this question: In order to use language and thought correctly, and to ensure the smooth progress of rational communication, should people follow certain general principles, assumptions, or laws? According to existing historical materials, they did indeed do so and each put forward relevant theories. These theories can be summarized into four most important ones: the law of identity, the law of contradiction, the law of excluded middle, and the 'law of sufficient reason' that came from Leibniz in the 17th century."

"The so-called law of identity is what Plato pointed out in Phaedo: thought must be consistent with itself, and all our convictions must be consistent with each other."

"In other words, the law of identity requires that in the same thought process, a concept should be used in that unique and definite sense from beginning to end. That is to say, you should discuss the topic you are discussing, and you cannot deviate from the topic or go off-topic. The function of the law of identity is to ensure certainty in the same thinking, the same expression, the same conversation, and the same debate."

"Only by ensuring uniformity can logic and logical debate have a foundation; otherwise, logical argumentation cannot begin."

“For example, yesterday I asked my third aunt: ‘Does Tiedan ever misbehave?’ My third aunt replied: ‘Tiedan used to wet the bed a little, but after eating sandworms in Liangshan, he hasn’t wet the bed since.’ This is not following the ‘law of identity’.”

"Not wetting the bed doesn't mean not being naughty. Even if a child wets the bed before, that's a normal physiological phenomenon and can't be equated with being naughty. This doesn't follow the principle of 'identity' and is an illogical answer."

"Regarding the law of identity, the Mohist school states in the *Jing Shuo Xia* that 'the rectification of names means that 'that' stops at 'that,' and 'this' stops at 'this,' and they cannot be mutually exclusive.' The so-called 'mutual exclusive' refers to the arguments of the two opposing sides. Mozi believed that the name of 'that' can only refer to the reality of 'that,' and the name of 'this' can only refer to the reality of 'this.' Therefore, the Mohist principle of 'rectification of names' is actually the 'law of identity' in Western logic. The Mohist principle of 'understanding the meaning before debating' means that in a debate, one must first 'understand the meaning,' that is, both sides must have a consistent and accurate understanding of the 'concepts' in the topic before they can debate. This is also a precise description of how the 'law of identity' is applied."

"The famous scholars' claims about 'a white horse is not a horse' and 'a solid stone is not a stone' further emphasize the classic assertion of the law of identity—a noun that has been modified by a noun has already deviated from the noun itself in terms of conceptual meaning and can no longer be regarded as the same concept. The emphasis on the law of identity has reached a very subtle level."

"The second essential tenet of logic is the law of contradiction, which is easier to understand. Aristotle pointed out in his book *Metaphysics*: 'The same thing cannot both exist and not exist at the same time, nor can it be opposed to itself in the same way.' 'Opposing statements cannot both be true.' 'Answering claims about the same thing can never be true.'"

"This is the first premise of the law of contradiction. Next is the second premise of the law of contradiction, which should be called the law of prohibition of contradiction or the law of non-contradiction. Its content is that two mutually contradictory or opposing propositions cannot both be true, but can both be false, and one of them must be false. Otherwise, it will commit the logical fallacy of 'self-contradiction'."

"The most well-known example is the story of 'self-contradiction' in Han Feizi."

"We often see similar errors in announcements, such as: 'Touching the power lines is strictly prohibited! 500 volts of high voltage will kill you instantly. Violators will be prosecuted!' Since touching them will result in death, there's no way to prosecute a dead person—this is a contradiction." "The *Mo Jing* describes this as, 'Some call it an ox, some call it not an ox; this is arguing about which. Neither is entirely correct; either must be incorrect.'"

"This means that the controversy over the argument is actually a controversy over a pair of contradictions, namely, whether they are true or false. A pair of contradictions cannot both be 'truths,' and one of them must be 'untruths.'"

"The third law of logic is the law of excluded middle, which Aristotle explicitly stated: 'No mediator is allowed between opposing statements, and for the same thing one must either affirm or deny one aspect. This is quite clear to those who define what is true and false.'"

The *Mo Jing* states: "That is neither mutually agreeable nor mutually unacceptable." "What is meant by 'not the same' is 'different.' Neither can prevail; this is the absence of debate. Debate involves either calling something right or wrong; the one who is right wins."

"This means that for two contradictory propositions, the holders of the argument cannot both affirm or both deny them; it must be one and the other not. However, for the two sides discussing the same proposition, they must 'disagree' and there cannot be any 'acceptable' part, because the 'acceptable' part does not need to be disputed. What is being discussed is the 'truthfulness' of the 'disagreeable' part."

"Combining the contents of the law of contradiction and the law of excluded middle, it is actually that any proposition must be either true or false, either true or false. This is the so-called 'two-value principle,' and the logic generally used is based on the two-value principle of truth and falsehood."

"The final law of logic is the principle of sufficient reason. Although ancient Greek philosophers particularly emphasized the role of reasoning and argumentation, and constructed many famous examples of reasoning and argumentation, the first to explicitly articulate the principle of sufficient reason was actually the 17th-century German philosopher and mathematician Leibniz. He believed that our reasoning is based on two major principles: one is the principle of contradiction, which states that self-contradiction is not allowed in thought; the other is the principle of sufficient reason: 'If anything is true or real, if any statement is true, there must be a sufficient reason why it is this way and not that way, although these reasons are often unknown to us.'"

"In other words, the premise for logic to hold true is the full fulfillment of known conditions. This is not actually a fundamental law of logic, nor is it the reason for logic to hold true, but it is the reason for logic to be ultimately correct. This involves three elements: First, reasons must be given for the viewpoint to be argued; second, the reasons given must be true; and third, the reasons given must be able to lead to the argument to be argued."

"Otherwise, one will make the mistakes of 'no reason,' 'false reason,' and 'inability to deduce.' The principle of sufficient reason serves to ensure the persuasiveness of reasoning."

"The principle is very simple. For example, the shortest distance between two points is a straight line, but this is only true under the conditions of plane geometry. Another example is Newton's three laws of motion, which are only correct under the constraints of classical physics. In the context of the universe, the three laws of motion are replaced by relativity."

"Regarding this point, the *Mo Jing* already stated: 'Words arise from reason. To establish a statement without clarifying its origin is vain.' That is to say, arguments arise from reason, and to propose an argument without clarifying the reasons upon which it arises is vain." (End of Chapter)