17. The following whimsical syllogisms are by Lewis Carroll. They are intended to illustrate that logical syntax depends only on the form of the argument, not on the meaning or truth of the statements. Which of them are correct arguments? (a) No frogs are poetical; some ducks are unpoetical. Hence, some ducks are not frogs. (b) Gold is heavy; nothing but gold will silence him. Hence, noth- ing light will silence him. (c) All lions are fierce; some lions do not drink coffee. Hence, some creatures that drink coffee are not fierce. (d) Some pillows are soft; no pokers are soft. Hence, some pokers are not pillows.
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It then concludes that some ducks are not frogs. This argument is not correct because being poetical or unpoetical does not have any logical connection to being a frog or not. Show more…
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