A chapter is given to the Cross-fertilization of Fallacies. The author shows how two half-truths brought together from two widely separated fields of thought will produce a new and magnificently variegated form of opinion. The hybrid will surpass specimens of either of the parent stocks both in size and showiness. Thus a half-truth of popular religion cross-fertilized by a half-truth of popular science will produce a hybrid which astonishes both the religious and the scientific world. If we were following the analogy of mathematics we might assume that two half-truths would make a whole truth. But when we are dealing with the marvelous reproductive powers of nature we find that they make much more than that.
Scholasticus gives a page or two to the Dwarfing of Arguments. “The complaint is sometimes heard that an argument which is otherwise satisfactory proves too much. This may seem a good fault to those whose chief difficulty is in making their arguments prove anything at all. But I assure you that it is really very troublesome to find that you have proved more than you intended. You may have no facilities for dealing with the surplus conclusions, and you may find all your plans disarranged. For this reason many persons, instead of cultivating arguments of the standard sizes which take a good deal of room, prefer the dwarf varieties. These are very convenient where one does not wish one principle to crowd out another that may be opposed to it. Persons inclined to moderation prefer to cultivate a number of good ideas without crowding. The dwarf varieties are pleasing to the cultivated taste, as they are generally exceedingly symmetrical, while full-grown ideas, especially in exposed places, are apt to impress one as being scraggly.
“Dean Swift, who had no taste for miniature excellencies, spoke scornfully of those who plant oaks in flower-pots. I have, however, frequently seen very pleasing oaks grown in this way, and they were not in very big flower-pots, either.
“In moral reasoning, it is especially difficult to keep our conclusions moderate enough for our convenience. An ordinary argument always tends to prove too much. This is disconcerting to those who are endeavoring to live up to their favorite text, ‘Be not overmuch righteous.’ The danger of overmuchness is obviated by cultivating the fashionable dwarf varieties of righteousness.
“Various methods of dwarfing are practiced with success. Training will do much; you have seen trees dwarfed by tying them to a trellis or against a wall or to stakes, and preventing their growth beyond the prescribed limits. Incessant pruning is necessary, and each new growth must be vigorously headed back. By using the same means we may cultivate a number of fine ideas, and at the same time keep them fairly small.”
The least satisfactory chapter is that on Pests. “It is easy enough,” says Scholasticus, “to describe a pest, but it is another matter to get rid of it. The most painstaking fallacy culturist must expect to awake some morning and behold his choicest arguments laid low by some new kind of critic. There seems to be no limit to the pestiferous activity of these creatures. They are of two kinds: those that bite, cutting off the roots of the argument, and those that suck out the juices. These latter destroy the vital tissue of inference on which everything depends. I never met any one who cultivated arguments on a large scale who did not have his tale of woe.
“I had at one time a theological friend who had great reputation as a dogmatist. He had for many years a garden of fallacies which was one of the show places. It was in a sheltered situation, so that many fine old dogmas flourished which we do not often, in these days, see growing out of doors. Everything went well until the locality became infested with destructive criticism. He tried all the usual remedies without success. At last he became utterly discouraged, and cut out all the dead wood, and uprooted all the dogmas that were attacked by the pest. Since then he has given up his more ambitious plans, and he has only a simple little place where he cultivates those fruits of the spirit which are not affected by destructive criticism. It is only fair to say that he is making a very pleasant place of it.
“For the encouragement of those who are not ready to take such heroic methods, it may be said that eternal vigilance, though not a panacea, will do much. Some of the most dreaded species of critics are not so dangerous as they seem. Many persons fear the Criticus Academicus. I have, however, seen fallacies which survived the attacks of this species and fell easy victims to the more troublesome Criticus Vulgaris, or Common Gumption.
“The worst pest is what is known as the Reductio ad Absurdum. This is a kind of scale which grows upon a promising argument and eats out its life. It is so innocent in its appearance that at first one does not suspect its deadly character. In fact, it is sometimes taken as an agreeable ornament. After a little while the argument is covered over with a sort of dry humor. There is then no remedy.”
In the chapter on the use of artificial fertilizers, Scholasticus deals particularly with statistics. He refers incidentally to their use in the cultivation of valid arguments. Their importance here is universally acknowledged. “It should be remembered,” he says, “that in this case success depends upon the extreme care with which they are used. An unusual amount of discrimination is demanded in their application. For this reason, if solid conclusions, that head well, are expected, only experts of good character can be trusted to do the work.