CHAPTER XV. ILLUSTRATIVE EXERCISES

1. All men possessed of an uncontrolled discretionary power, leading

to the aggrandisement and profit of their own body, have always abused

it.'--Burke's Thoughts on the Present Discontents.

The student will find the proof of this proposition exhibited in the

example of Induction, quoted from Mr. Bailey, p. 63.

2. Prosperity could never be reached and maintained in this country,

without some provision for the regular employment of the poor.--Mr.

Beckett's Speech in the House of Commons, Feb. 3,1842.

The demonstration, to universal conviction, of this proposition, would

lead to an entire and beneficial change of the social condition of this

country.

3. The pen is the tongue of the world.--Paine. Put this in the

syllogistic form.

4. A good instance of a metaphorical argument drawn out is given by Mr.

Mill:--'For instance, when Mr. Carlyle, rebuking the Byronic vein, says

that "strength does not manifest itself in spasms, but in stout bearing

of burdens;" the metaphor proves nothing, it is no argument, only

an allusion to an argument; in no other way however could so much of

argument be so completely suggested in so few words. The expression

suggests a whole train of reasoning, which it would take many sentences

to write out at length. As thus: Motions which are violent but brief,

which lead to no end, and are not under the control of the will, are,

in the physical body, more incident to a weak than to a strong

constitution. If this be owing to a cause which equally operates in what

relates to the mind, the same conclusion will told there likewise. But

such is really the fact. For the body's liability to these sudden

and uncontrollable motions arises from irritability, that is, unusual

susceptibility of being moved out of its ordinary course by

transient influences: which may equally be said of the mind. And this

susceptibility, whether of mind or body, must arise from a weakness

of the forces which maintain and carry on the ordinary action of the

system. All this is conveyed in one short sentence. And since the causes

are alike in the body and in the mind, the analogy is a just one, and

the maxim holds of the one as much as of the other.'*

* Logic, pp. 433-4, vol. 2.

5. A youth, named Evathlus, engaged with Protagoras to learn dialectics,

and promised his tutor a large sum of money, _in case he gained the

first cause he pleaded_, Evathlus, when fully instructed, refused to pay

his instructor. Protagoras brought his action thus--'You must pay the

money however the cause go, for if I gain you must pay in consequence of

the sentence, as being cast in the cause; and if you gain it, you must

pay in pursuance of our covenant.' 'Nay,' Evathlus retorts, 'which way

soever the cause be decided, you will have nothing, for if I prevail,

the sentence gives it that nothing is due: and if I lose, then there is

nothing due by the covenant.' What should be the decision in this case?

6. The first case, says Cervantes, requiring Sancho's attention was a

question put by a stranger, in presence of the stewards and rest of the

attendants. 'My Lord,' said he, 'a certain manor is divided by a large

river. I beg your honour will be attentive, for the case is of great

consequence and of some difficulty. I say then, upon this river is a

bridge, and at one end of it the gibbet, together with a sort of court

hall, in which four judges usually sit to execute the law enacted by the

lord of the river, bridge, and manor, which runs to this effect: Whoever

shall pass this bridge, must first swear whence he comes and whither

he goes; if he swear the truth he shall be allowed to pass, but if he

forswear himself he shall die upon the gallows without mercy or respite.

This law, together with the rigorous penalty, being known, numbers

passed, and as it appeared they swore nothing but the truth, the judges

permitted them to pass freely and without control. It happened, however,

that one man's oath being taken, he affirmed and swore by his deposition

that he was going to be hanged on that gibbet, and had no other errand

or intention. The judges, having considered this oath, observed: if we

allow this man to pass freely, he swore to a lie, and, therefore, ought

to be hanged according to law; and if we ordered him to be hanged after

he hath sworn he was going to be suspended on that gibbet, he will have

sworn the truth, and by the same law he ought to be acquitted, I beg,

therefore, to know, my lord governor [and student], what the judges must

do with this man?'

A Logic of Facts; Or, Every-day Reasoning · 第 15 / 16 章