21. QUESTIONS FOR ORIGINAL THOUGHT AND INVESTIGATION.
(1) May both premises of a hypothetical argument be hypothetical propositions? Explain. See Fowler p. 115.
(2) Which of the two is valid? Explain.
(1) If A is B, C is D
If A is B, E is F
∴ If C is D, E is F
(2) If A is B, C is D
If C is D, E is F
∴ If A is B, E is F
(3) Show by circles that two of the possible four hypothetical arguments are invalid.
(4) What categorical rules does the hypothetical argument seem to violate? Explain.
(5) Originate a hypothetical syllogism whose antecedent and consequent are both negative. Test its validity.
(6) Originate a co-extensive hypothetical argument and show that four valid syllogisms may be derived from it.
(7) Explain by word and illustration the two meanings which may be attached to “either-or.”
(8) If we accepted the opinion that both alternates of a disjunctive may be true, which kind of disjunctive argument would it invalidate?
(9) In a logical disjunction what law of thought is involved? Explain.
(10) Why do the laws of the disjunctive seem to contradict the categorical rules? Explain fully.
(11) Show by drawing on common experience that a logical dilemma is closely related to the popular conception of dilemma.
(12) Illustrate by symbols and then place in good English a pentalemma.
(13) State a definition of a dilemma which excludes the simple destructive form.
(14) Give a common experience which, when thrown into argumentative form, results in a disjunctive proposition followed by a hypothetical syllogism. Coin a name for such a combination.