Of all the tricks of controversy, this is the most frequent, and it is used instinctively. You hear of "religious zeal," or "fanaticism", a "faux pas," a "piece of gallantry," or "adultery"; an "equivocal," or a "bawdy" story; "embarrassment," or "bankruptcy"; "through influence and connection," or by "bribery and nepotism"; "sincere gratitude," or "good pay".
Sophistic & Logic
-This stratagem relies on a loaded question to get your opponent to reject one of his positions, thus showing he is paradoxical.
Original text
To make your opponent accept a proposition, you must give him the counter-proposition as well, leaving him his choice of the two; and you must render the contrast as glaring as you can, so that to avoid being paradoxical he will accept the proposition, which is thus made to look quite probable. For instance, if you want to make him admit that a boy must do everything that his father tells him to do, ask him "whether in all things we must obey or disobey our parents". Or, if a thing is said to occur "often," ash whether by "often" you are to understand few or many cases; and he will say "many". It is as though you were to put grey next black, and call it white; or next white, and call it black.
Sophistic & Logic
- This stratagem relies on the logic induction. It could be considered a case of the cherry-picking fallacy.
Original text
If you make an induction, and your opponent grants you the particular cases by which it is to be supported, you must refrain from asking him if he also admits the general truth which issues from the particulars, but introduce it afterwards as a settled and admitted fact; for, in the meanwhile, he will himself come to believe that he has admitted it, and the same impression will be received by the audience, because they will remember the many questions as to the particulars, and suppose that they must, of course, have attained their end.
Sophistic & Logic
- This stratagem is related to the 4th strategem "Conceal Your Game".
Original text
Or you may put questions in an order different from that which the conclusion to be drawn from them requires, and transpose them, so as not to let him know at what you are aiming. He can then take no precautions. You may also use his answers for different or even opposite conclusions, according to their character. This is akin to the trick of masking your procedure.
Sophistic & Logic
This stratagem is how to defend from an "ad hominem" fallacy attack. It is related to the "caricature" fallacy.
Original text
A Moor is black; but in regard to his teeth he is white; therefore, he is black and not black at the same moment. This is an obvious sophism, which will deceive no one. Let us contrast it with one drawn from actual experience.
In talking of philosophy, I admitted that my system upheld the Quietists, and commended them. Shortly afterwards the conversation turned upon Hegel, and I maintained that his writings were mostly nonsense; or, at any rate, that there were many passages in them where the author wrote the words, and it was left to the reader to find a meaning for them. My opponent did not attempt to refute this assertion ad rem, but contented himself by advancing the argumentum ad hominem and telling me that I had just been praising the Quietists, and that they had written a good deal of nonsense too.
This I admitted; but, by way of correcting him, I said that I had praised the Quietists, not as philosophers and writers, that is to say, for their achievements in the sphere of theory, but only as men, and for their conduct in mere matters of practice; and that in Hegel's case we were talking of theories. In this way I parried the attack.
The first three tricks are of a kindred character. They have this in common, that something different is attacked from that which was asserted. It would therefore be an ignoratio elenchi to allow oneself to be disposed of in such a manner.
For in all the examples that I have given, what the opponent says is true, but it stands in apparent and not in real contradiction with the thesis. All that the man whom he is attacking has to do is to deny the validity of his syllogism; to deny, namely, the conclusion which he draws, that because his proposition is true, ours is false. In this way his refutation is itself directly refuted by a denial of his conclusion, per negationem consequentiae. Another trick is to refuse to admit true premisses because of a foreseen conclusion. There are two ways of defeating it, incorporated in the next two sections.
Sophistic & Logic
This stratagem relies on the logical rules of induction. An induction argument is hard to make and easy to destroy.
Original text
This is a case of the diversion by means of an instance to the contrary. With an induction (epagoge), a great number of particular instances are required in order to establish it as a universal proposition; but with the diversion (apagoge) a single instance, to which the proposition does not apply, is all that is necessary to overthrow it. This is a controversial method known as the instance - instantia, eustasis. For example, "all ruminants are horned" is a proposition which may be upset by the single instance of the camel. The instance is a case in which a universal truth is sought to be applied, and something is inserted in the fundamental definition of it which is not universally true, and by which it is upset. But there is room for mistake; and when this trick is employed by your opponent, you must observe (1) whether the example which he gives is really true; for there are problems of which the only true solution is that the case in point is not true - for example, many miracles, ghost stories, and so on: and (2) whether it really comes under the conception of the truth thus stated: for it may only appear to do so, and the matter is one to be settled by precise distinctions; and (3) whether it is really inconsistent with this conception; for this again may be only an apparent inconsistency.
Sophistic & Logic
This stratagem is not linked to sophistic or logic.
Original text
When you state a question or an argument, and your opponent gives you no direct answer or reply, but evades it by a counter-question or an indirect answer, or some assertion which has no bearing on the matter, and, generally, tries to turn the subject, it is a sure sign that you have touched a weak spot, sometimes without knowing it. You have, as it were, reduced him to silence. You must, therefore, urge the point all the more, and not let your opponent evade it, even when you do not know where the weakness which you have hit upon really lies.
Sophistic & Logic
This stratagem relies on an invalid use of the logical implication in formal logic. Admitting the premisses but denying the conclusion (T T -> F)

Original text
"That's all very well in theory, but it won't do in practice." In this sophism you admit the premisses but deny the conclusion, in contradiction with a well-known rule of logic. The assertion is based upon an impossibility: what is right in theory must work in practice; and if it does not, there is a mistake in the theory; something has been overlooked and not allowed for; and, consequently, what is wrong in practice is wrong in theory too.
Sophistic & Logic
This stratagem relies on the "guilt by association" fallacy.
The "guilt by association" fallacy and this stratagem both rely on the Euler and Venn diagrams from mathematics/logic.

Original text
If you are confronted with an assertion, there is a short way of getting rid of it, or, at any rate, of throwing suspicion on it, by putting it into some odious category; even though the connection is only apparent, or else of a loose character. You can say, for instance, "That is Manichaeism" or "It is Arianism," or "Pelagianism," or "Idealism," or "Spinozism," or "Pantheism," or "Brownianism," or "Naturalism," or "Atheism," or "Rationalism," "Spiritualism," "Mysticism," and so on. In making an objection of this kind, you take it for granted that the assertion in question is identical with, or is at least contained in, the category cited - that is to say, you cry out, "Oh, I have heard that before"; and that the system referred to has been entirely refuted, and does not contain a word of truth.
Sophistic & Logic
This stratagem relies on the "appeal to emotion" fallacy.
Original text
Should your opponent surprise you by becoming particularly angry at an argument, you must urge it with all the more zeal; not only because it is a good thing to make him angry, but because it may be presumed that you have here put your finger on the weak side of his case, and that just here he is more open to attack than even for the moment you perceive.
Sophistic & Logic
This stratagem relies on a original form of the "ad hominem" fallacy.
Original text
Another trick is to use arguments ad hominem, or ex concessis.14 When your opponent makes a proposition, you must try to see whether it is not in some way - if needs be, only apparently - inconsistent with some other proposition which he has made or admitted, or with the principles of a school or sect which he has commended and approved, or with the actions of those who support the sect, or else of those who give it only an apparent and spurious support; or with his own actions or want of action. For example, should he defend suicide, you may at once exclaim, "Why don't you hang yourself?" Should he maintain that Berlin is an unpleasant place to live in, you may say, "Why don't you leave by the first train?" Some such claptrap is always possible.
14.) The truth from which I draw my proof may be either (1) of an objective and universally valid character; in that case my proof is veracious, secundum veritatem; and it is such proof alone that has any genuine validity. Or (2) it may be valid only for the person to whom I wish to prove my proposition, and with whom I am disputing. He has, that is to say, either taken up some position once for all as a prejudice, or hastily admitted it in the course of the dispute; and on this I ground my proof. In that case, it is a proof valid only for this particular man, ad hominem. I compel my opponent to grant my proposition, but I fail to establish it as a truth of universal validity. My proof avails for my opponent alone, but for no one else. For example, if my opponent is a devotee of Kant's, and I ground my proof on some utterance of that philosopher, it is a proof which in itself is only ad hominem. If he is a Mohammedan, I may prove my point by reference to a passage in the Koran, and that is sufficient for him; but here it is only a proof ad hominem.
The Art of Controversy - Schopenhauer
- 01 - Extension
- 02 - Homonymy
- 03 - Generalize your Opponent's Specific Statements
- 04 - Conceal your game
- 05 - False propositions
- 06 - Postulate What Has To Be Proved
- 07 - Yield Admissions through questions
- 08 - Make Your Opponent Angry
- 09 - Questions in Detouring Order
- 10 - Take Advantage of The Nay-Sayer
- 11 - Generalize Admissions of Specific Cases
- 12 - Choose Metaphors Favourable to Your Proposition
- 13 - Agree to Reject the Counter-Proposition
- 14 - Claim Victory Despite Defeat
- 15 - Use Seemingly Absurd Propositions
- 16 - Arguments Ad Hominem
- 17 - Defense Through Subtle Distinction
- 18 - Interrupt, Break, Divert the Dispute
- 19 - Generalize the Matter, Then Argue Against it
- 20 - Draw Conclusions Yourself
- 21 - Meet him With a Counter-Argument as Bad as His
- 22 - Petitio Principii
- 23 - Make Him Exaggerate his Statement
- 24 - State a False Syllogism
- 25 - Find One Instance to The Contrary
- 26 - Turn The Tables
- 27 - Anger Indicates a Weak Point
- 28 - Persuade the Audience, Not The Opponent
- 29 - Diversion
- 30 - Appeal to Authority Rather Than Reason
- 31 - This is Beyond Me
- 32 - Put His Thesis Into Some Odious Category
- 33 - It Applies in Theory, But Not in Practice
- 34 - Don't Let Him Off The Hook
- 35 - Will is More Effective Than Insight
- 36 - Bewilder Your opponent by Mere Bombast
- 37 - A Faulty Proof Refutes His Whole Position
- 38 - The Ultimate Stratagem
- Intro I - Logic And Dialectic
- Intro II - Controversial Dialectic
- Intro III - The Basis Of All Dialectic