Criticism of the Board of Assessors comes with poor grace from those whose endeavors for the common good are confined to academic essays on good government. It savors too much of the adroit pickpocket, who, finding himself hard pressed, joins in the chase, shouting as lustily as any of the unthinking rabble, "Stop, thief!"
The curious thing is that this trick of crossing the scent does lead so many people off the trail.
The so-called argumentum ad hominem and the argumentum ad populum are special cases of ignoring the question: they consist of appeals to the feelings or special interests of the reader or the audience which run away from the question at issue. They are not uncommon in stump speeches, and in other arguments whose chief purpose is to arouse enthusiasm.
An argument on the tariff, for example, sometimes runs off into appeals to save this grand country from ruin or from the trusts or from some other fate which the speaker pictures as hanging over an innocent and plain people. An argument for the restoration of the classical system of education which should run off into eulogies of the good old times might easily become an argumentum ad populum; an argument in favor of a new park which should dwell on selfish advantages which might be gained by the abutters without regard to larger municipal policy would probably be an argumentum ad hominem.
Obviously these two forms of shifting the issue trench closely on the element of persuasion in an argument, and in making the distinction you must apply common sense. Your adversary may reprove you for an argumentum ad hominem or ad populum, when you believe that you are keeping well within the bounds of legitimate persuasion; but in general it is safe to guard your self-respect by drawing a broad line between dodging and unworthy appeals to prejudice and justifiable appeals to feeling and personal interest.
EXERCISES
1. Name a question of policy which would be settled by the establishment of some controverted fact.
2. Find in the daily papers an account of a trial in which evidence was declared inadmissible under the rules of law which would have been taken into account by the average man outside the court in making up his own mind.
3. Name three questions in which the evidence would be affected by temperamental and other prepossessions of the witness.
4. Name a scientific question in which some important fact is established by reasoning from other facts.