11. ILLUSTRATIVE EXERCISES.
(1a) Examine the following list of propositions with a view to classifying them as “A’s,” “E’s,” “I’s” or “O’s.”
E 1. “None of the inmates voted.”
A 2. “Benj. Franklin was the best educated American.”
I 3. “Some doctors deem it right to lie to their patients.”
A 4. “All earnest teachers need to observe the teaching of others.”
I 5. “Some politicians are honest.”
A 6. “Fools rush in where angels fear to tread.”
O 7. “Some proverbs are not true to life.”
E 8. “No man should infringe upon the rights of others.”
I recall that an affirmative proposition in which the predicate refers to the whole of the subject is an A, while one where the predicate refers to only a part of the subject is an I. Further, a negative proposition where the predicate refers to the whole of the subject is an E, while one in which the predicate refers to only a part of the subject is an O. With these facts in mind, I classify the propositions as indicated.
(1b) In a similar manner classify as to quantity and quality the following:
(1) “All worthy workers grow to look like their work.”
(2) “Every dog has his day.”
(3) “Some of the presidents were not popular.”
(4) “No unskilled laborer can afford to own an automobile.”
(5) “Some of the ‘election prophets’ were sadly mistaken.”
(2a) Classify the following propositions and make the illogical, logical:
(1) “Only first-class passengers may ride in parlor cars.”
(2) “Haste makes waste.”
(3) “Few men know how to act under stress.”
(4) “All which seems to ring true is not true.”
(5) “Members alone are admitted.”
(6) “None but men of integrity need apply.”
(7) “Horses trot.”
(8) “Blessed are they which are persecuted for righteousness sake.”
The first proposition is an exclusive and may be made logical by converting and calling it an A, viz.: “All who ride in parlor cars are first-class passengers.” (A)
The second is indefinite and elliptical and is made logical by prefixing the universal quantity sign and expressing in terms of the four elements. The logical form is, “All who make haste are those who are wasteful.” (A)
The third is plurative in nature and means, “Most men do not know how to act under stress.” It would be classed as an O.
The fourth is partitive in nature because of the ambiguous use of “all—not.” It means, “Some who seem to ring true are not true.” (O)
The fifth is an exclusive. By converting and changing to an A the proposition takes the logical form, “All who are admitted are members.”
The sixth is likewise an exclusive, the logical form being, “All who apply must be men of integrity.”
The seventh is an elliptical proposition. Logical form: “All horses are trotting animals.”
The eighth is an inverted or poetical proposition. It is made logical by interchanging subject and predicate. Logical form: “Those who are persecuted for righteousness sake are blessed.”
(2b) Classify the attending propositions and change to the logical form, if necessary:
(1) “Only truthful men are honest.”
(2) “The stokers alone were saved.”
(3) “All who run do not think.”
(4) “Honesty is the best policy.”
(5) “They laugh that win.”
(6) “The good alone are happy.”
(7) “Knowledge is power.”
(8) “Only the actions of the just smell sweet and blossom in the dust.”