'Some speculative men are unworthy of trust; for they are unwise, and no unwise man can be trusted.' I. Unwise men | are not to be trusted ---------------------+----------------------------- Some speculative men | _they are not to be trusted_ are unwise *** 'No idle person can be a successful writer of history; therefore Hume, Macaulay, Hallam and Grote must have been industrious.' I. Successful historians | are not idle persons -----------------------+--------------------- Hume and the rest were | _they cannot have successful historians | been idle persons_ *** 'Lithium is an element; for it is an alkali-producing substance, which is a metal, which is an element.'--Fallacy of no-application. Every alk. | is a metal || Every metal | is an element prod. subst. | || | -------------+-----------------++---------------+------------------- L. is alk. | _it is a metal_ || L. is a metal | _it is an element_ p. subst. | || | *** 'Rational beings are accountable for their actions; brutes not being rational, are therefore exempt from responsibility.' I. Rational beings | are accountable --------------------+---------------- Brutes not rational | _N. C._ *** 'Whatever tends to withdraw the mind from pursuits of a low nature deserves to be promoted; classical learning does this, since it gives us a taste for intellectual enjoyments; therefore it deserves to be promoted.' V. I. Whatever gives | tends || Whatever tends | deserves ---------------+------------++----------------+-------------- Learning gives | _it tends_ || Learning tends | _it deserves_ *** 'Bacon was a great lawyer and statesman; and as he was also a philosopher, we may infer that any philosopher may be a great lawyer and statesman.'--The theorem infers the general inherence of philosophy with eminence in law and politics, from the single instance of Bacon: it is evidently a fallacy of doubtful precedent. *** 'Snowdon is the highest mountain in England and Wales. Snowdon is not so high as Ben Nevis. Therefore the highest mountain in England and Wales is not so high as Ben Nevis.' This means: 'the highest mountain in England and Wales is called Snowdon, and it is not so high as Ben Nevis.' The apparent conclusion merely repeats a part of the information given already. There is no case. The following is a theorem of the same kind-- 'Lithium is the lightest metal known. Lithium is the metal indicated by one bright line in the spectrum. Therefore the lightest metal known is the metal indicated by a spectrum of one bright line.' *** 'If ye were Abraham's children, ye would do the works of Abraham.'