Practical Argumentation by George K. Pattee (summer reading list .txt) 📖

of, and when the “value of money” is said to be high or low, the rate of interest being meant. The consequence of this ambiguity is, that as soon as scarcity of money in the latter of these senses begins to be felt,—as soon as there is difficulty of obtaining loans, and the rate of interest is high,—it is concluded that this must arise from causes acting upon the quantity of money in the other and more popular sense; that the circulating medium must have diminished in quantity, or ought to be increased. I am aware that, independently of the double meaning of the term, there are in the facts themselves some peculiarities, giving an apparent support to this error; but the ambiguity of the language stands on the very threshold of the subject, and intercepts all attempts to throw light upon it.

As countless words and expressions have several meanings, there is almost no limit to the confusion which this fallacy can cause. Some of the most common terms that are used ambiguously are right, liberty, law, representative, theory, church, state, student.

By carefully defining all terms that have more than one meaning and by insisting on a rigid adherence to the one meaning wherever the term is used, a debater can easily avoid fallacies of this sort in his own argument and expose those of his opponent.

 

III. FALSE CAUSE.

The fallacy of false cause occurs whenever that which could in no way bring about the effect that is being established is urged as its cause. This fallacy in its most obvious form is found only in the arguments of careless and illogical thinkers. Some college students occasionally draw briefs that contain such reasoning as the following:—

I. The Panama canal should be of the sea-level rather than of the lock type, because

A. The Panama canal will do away with the long voyage around the Horn.

I. Southerners are justified in keeping the franchise away from the negro, for

A. Negroes should never have been brought to America.

B. The Fifteenth Amendment to the Constitution ought not to have been passed.

The error of such plainly absurd reasoning as occurs in the preceding illustrations needs no explanation. There is one form of the fallacy of false cause, however, that is much more common and insidious and therefore deserves special treatment.

POST HOC ERGO PROPTER HOC. (After this, therefore, on account of this.) This phase of the fallacy consists of the assumption that since cause precedes effect what has preceded an event has caused it. The most frequent occurrence of the error is to be found in superstitions. If some one meets with an accident while taking a journey that began on Friday, many people will argue that the accident is the effect of the unlucky day. Some farmers believe their crops will not prosper unless the planting is done when the moon is in a certain quarter; sailors often refuse to embark in a renamed vessel. Because in the past, one event has been known to follow another, it is argued that the first event was the cause of the second, and that the second event will invariably follow the first.

But this fallacy does not find its only expression in superstitions. To post hoc reasoning is due much of the popularity of patent medicines. Political beliefs, even, are often generated in the same way; prosperity follows the passing of a certain law, and people jump to the conclusion that this one law has caused the “good times.” Some demagogues go so far as to say that education among the Indians is responsible for the increased death rate of many of the tribes.

A slightly different phase of the post hoc fallacy consists in attributing the existence of a certain condition to a single preceding event, when at the most this event could have been only a partial cause of what followed, and may not have been a cause at all. A medicine that could not have effected a cure may have been of some slight benefit. A law that could not possibly have been the sole cause of “good times” may have had a beneficial effect. To avoid this fallacy, one must be sure not only that the assigned cause is operative, but that it is also adequate.

In the following passage, Harpers Weekly, for March 5, 1894, points out the error in the reasoning made by several college presidents who, after compiling statistics, stated that a college education increased a man’s chance of success from one in ten thousand to one in forty:—

Not many persons doubt any longer that an American college education is an advantage to most youths who can get it, but in these attempts to estimate statistically what college education does for men there is a good deal of confusing of post hoc and propter hoc. Define success as you will, a much larger proportion of American college men win it than of men who don’t go to college, but how much college training does for those successful men is still debatable. Remember that they are a picked lot, the likeliest children of parents whose ability or desire to send their children to college is evidence of better fortune, or at least of higher aspirations than the average. And because their parents are, as a rule, more or less prosperous and well educated, they get and would get, whether they went to college or not, a better than average start in life….

If one boy out of a family of four goes to college, it is the clever one. The boys who might go to college and don’t are commonly the lazy ones who won’t study. The colleges get nowadays a large proportion of the best boys of the strongest families. The best boys of the strongest families would win far more than their proportionate share of success even if there were no colleges.

An exposure of similarly fallacious reasoning is made by Edward M. Shepard in The Atlantic Monthly for October, 1904.

The Republican argument is that the whole edifice of our prosperity depends upon high protective or prohibitive duties, and that to them is due our industrial progress. Is it not, indeed, a disparagement of the self-depending faculties of the American people thus to affirm that, in spite of their marvelous advantages, they would have failed in industrial life unless by force of law they could have prevented the competition with them of other peoples? It is only by the sophistry to which I have referred that this disparagement is justified. It is that old argument of veritable folly that, because event Z follows event W, as it follows events A and B and many besides A, therefore W is the sole cause of Z. Theory or no theory, the Republican says that we have in fact grown rich by protection, because in our country prosperity and protective duties have existed together. They ignore every inconvenient fact. They would have us forget that each of the industrial depressions of 1873-78 and 1893-96 followed long operation of a high protective tariff. They ignore the contribution of soil and climate to our prosperity, the vast increase which modern inventions and improved carrying facilities have, the world over, brought to the productivity of labor, and here in the United States have brought more than anywhere else. They ignore the superior skill and alertness of the American workman and the wonderful extent to which he has been stimulated by the conditions and ideals of our democracy. They ignore the freedom of trade, which, since 1789, the Federal Constitution has made operative over our entire country,— by far the most important area of free trade ever known,—and which everyone to-day knows to be a prime condition of the prosperity of our forty-five commonwealths.

From what has been said it is obvious that it is never safe to account for an occurrence or a condition by merely referring to something that accompanies it or precedes it. There must be a connection between the alleged cause and the effect, and this connection must be causal; otherwise, both may be the result of the same cause. The cause must also be adequate; and it must, moreover, be evident that the result has not been produced, wholly or partially, by some other cause or causes.

 

IV. COMPOSITION AND DIVISION.

COMPOSITION. The fallacy of composition consists of attributing to a whole that which has been proved only of a part. To condemn or to approve of a fraternity because of the conduct of only a few of its members, to say that what is advantageous for certain states in the Union would therefore be beneficial for the United States as a whole, to reason from the existence of a few millionaires that the English nation is wealthy, would be to fall into this fallacy. Furthermore, it is fallacious to think that because something is true of each member of a class taken distributively, the same thing holds true of the class taken collectively. It is not logical to argue that because each member of a jury is very likely to judge erroneously, the jury as a whole is also very likely to judge erroneously. Because each witness to an event is liable to give false or incorrect evidence, it is unreasonable to think that no confidence can be placed in the concurrent testimony of a number of witnesses.

DIVISION. The fallacy of division is the converse of the fallacy of composition. It consists of attributing to a part that which has been proved of the whole. For instance, Lancaster county is the most fertile county in Pennsylvania, but that fact by itself does not warrant the statement that any one particular farm is exceptionally fertile. Because the people of a country are suffering from famine, it does not follow that one particular person is thus afflicted. Again, it would be fallacious to say: It is admitted that the judges of the court of appeal cannot misinterpret the law; Richard Rowe is a judge of the court of appeal; therefore he cannot misinterpret the law.

 

V. IGNORING THE QUESTION. (IGNORATIO ELENCHI.)

An arguer is said to ignore the question, or to argue beside the point, whenever he attempts to prove or disprove anything except the proposition under discussion. This fallacy may arise through carelessness or trickery. An unskilled debater will often unconsciously wander away from his subject; and an unscrupulous debater, when unable to defend his position, will sometimes cunningly shift his ground and argue upon a totally new proposition, which is, however, so similar to the original one that in the heat of controversy the change is hardly noticeable. A discussion on the subject, “The boycott is a legitimate means of securing concessions from employers,” which attempted to show the effectiveness of the boycott, would ignore the question. Likewise, in a discussion on the proposition, “The average college student could do in three years the work now done in four,” any proof showing the desirability of such a crowding together of college work would be beside the point.

In the following passage Macaulay holds up to scorn certain arguments which contain this fallacy:—

The advocates of Charles, like the advocates of other malefactors against whom overwhelming evidence is produced, generally decline all controversy about facts, and content themselves with calling testimony to character.

We charge him with having broken his coronation oath; and we are told that he kept his marriage vow! We accuse him of having given up his people to the merciless inflictions of the most hot-headed and hard-hearted of prelates; and the defence is, that he took his little son on his knees and kissed him! We censure him for having violated the articles of the Petition of Rights, after having, for good and valuable consideration,