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What is a logical fallacy? A logical fallacy is a statement that pretends to be logical without complying with the rules of logic. The better the logical fallacy is disguised, and the more difficult it is to notice, the more dangerous it becomes (or more effective, depending on your position) and requires a greater effort in exposure.

It is important to emphasize that there are types of persuasion that are not based on logic, and therefore are not actually logical failures, for example an emotional argument or a command. An emotional argument, also known as emotional blackmail, plays on emotion rather than logic, for example "Jesus loves you, how can you not believe in him?" On the other hand, an order is based on authority and not on logic, for example "If you don't arrive on time, Shabbat will remain" or "You will tidy up the room because I am your mother and I said so". In these cases, the argument is not logical, but it also does not pretend to be so, so it is not a logical fallacy.

Is a logical fallacy an absolute thing

Not necessarily. Logical fallacies can be divided into those whose very existence is against logic, and in contrast there are fallacies that started with a permissible logical action and then deviated from it. Comparing traffic laws, one can say that the first type is similar to driving through a red light while the second type is similar to a dangerous overtaking. In my personal opinion, using a logical fallacy of the second type is more common but may be due to over-enthusiasm, lack of tact or stupidity. On the other hand, a logical fallacy of the first kind is almost always a sign of manipulativeness and bad intent.

Complete logical fallacies
These are failures in which the message goes against the laws of logic and takes advantage of the audience's ignorance or inattention to hide. For example, "All terrorists are Arabs, and terrorists deserve to die, so Arabs should be killed." In this example, the logical fallacy is in the intentional confusion between "all terrorists are Arabs" and "all Arabs are terrorists". Note that one can also find factual problems in the argument (Baruch Goldstein was Jewish) and value problems (is the death penalty appropriate?), but these problems are not a logical fallacy.

Relative logical fallacies
These are failures in which a legitimate action was exaggerated and became illegitimate. These failures take advantage of the fact that when the absolute laws of logic are based on facts from relative reality, a gray area is created that can be exploited for demagogic purposes.

For example - an analogy argument that says "the struggle for the rights of gays today is similar to the struggle for the rights of the Jews two hundred years ago, therefore whoever opposes it is a dark conservative" is relatively legitimate. While an analogy argument that says "the fight for animal rights today is similar to the fight for the rights of the Jews two hundred years ago, therefore whoever opposes animal experiments is a Nazi" is less legitimate because gays are not animals, and conservatism is not Nazism. The point is that the two example arguments presented are not absolute, and the degree of logical fallacy in the second compared to the first is one of degree and not substance.

How to spot a logical fallacy

Unfortunately there is no easy way to detect logical fallacies, for the simple reason that if there were they would not exist. The very existence of logical manipulations is because they sound close enough to valid logic to be convincing. Therefore, correct identification of logical fallacies requires familiarity with the rules of logic, familiarity with types of logical fallacies, and an alert and sharp mind.