Logical failures - rhetorical manipulations and demagoguery

This group of logical fallacies includes some of the crudest manipulations, used by those who really have no rational arguments. It is almost impossible to use these fallacies 'accidentally' and therefore when you encounter a speaker who uses them you can assume ill will.

 Argumentum ad nauseam - hForeign again and again

This is the favorite method of propaganda and advertising people, when appropriately the one who described its effectiveness best was the Nazi Minister of Propaganda Joseph Goebbels "Any lie you repeat enough times will be accepted as truth".

The reason why the technique works is a psychological phenomenon known as 'social desire' in which we strive to fit into society and be similar to others. When enough people around repeat a message (for example that the earth is flat or that there is no partner for peace) we are automatically convinced. The repetition technique relies on the fact that our emotional thinking does not always distinguish between a repeated message from the same source and a consensus that we hear from several people.

Argumentum ad ignorantiam - argument from ignorance

This logical fallacy occurs when it is claimed that something must be true, only because it has not yet been proven false. Or, equally, when it is claimed that something must be false, only because it has not yet been proven to be true.
(Note that this is not the same as assuming something is false until proven true. In the legal system, for example, you are usually assumed to be vindicated until proven guilty.)

The most interesting example is the 'Book of Mormon' authored by Joseph Smith who claimed that Jews arrived in America during the time of Christ and this is the origin of the Indians. When genetic research revealed that the Indians came from China, Mormon orthodoxy became an argument out of ignorance, 'It is impossible to prove that no Jew crossed the Atlantic Ocean.'

The fallacy of the secondary argument

This is an exercise in which you insert another, smaller, secondary argument into the main argument, which is rhetorically effective, but is sometimes small enough for the other side not to bother contradicting it.
For example: "The Prime Minister harmed the security of the country and lied to the people when he decided to cut the future fighter jet. The reason is that without the plane we are exposed to threats from enemies and our deterrence is compromised" - note that the argument proved a breach of security but not a lie.

This approach is reminiscent of the subliminal advertising method in which images and messages were embedded in the video advertisement that appeared a fraction of a second. The viewers did not consciously notice these messages, but the messages went straight to their subconscious and made them consume the product.

Complex question - putting more information in the question

This is a logical fallacy that is very similar to the secondary argument fallacy, and the difference is that the additional information is put into the question and not into the argument, and that the question already assumes information. This logical fallacy is less effective when speaking in front of an audience and more so in small meetings or in media interviews because it operates within a dialogue of questions and answers.
A classic example is the following question: "Have you stopped beating your wife?"
The question assumes that there is an absolute answer to another question that was never asked. Lawyers sometimes use this demagogic trick during cross-examination, with questions like: "Where did you hide the money you stole?" Similarly, politicians use the same trick: "How long will the European Union be allowed to interfere in our affairs?"

 Shifting the burden of proof

The burden of proof is always on the person claiming something. Shifting the burden of proof, a private case of an argument in the name of ignorance, is the fallacy of claiming that the burden of proof lies with those who disagree with the claim. The reason this is a fallacy is that something is assumed to be true until proven otherwise.
"Okay, so you don't think aliens landed here and took over the government, but can you prove it?"

It is important to emphasize that this logical fallacy, unlike the others brought up, may actually sometimes be legitimate when it changes the perspective of the discussion (re-framing). For example, if I want to deny the right of politicians to immunity from paparazzi I can make rational arguments about freedom of speech and the public's right to know. However, I can also reverse the burden of proof and require the other side to prove that the censorship law allows the censoring of nude photos of politicians (he doesn't). In this way, the discussion moved to the opponent's field, but this does not affect the validity of each side's argument.

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