Chapter 9

1.I have been out for a walk;I am feeling better.

Univ. is “persons”;m= the Class of I’s;x= persons who have been out for a walk;y= persons who are feeling better.

i.e. Somebody, who has been out for a walk, is feeling better.

pg1392.No one has read the letter but John;No one, who hasnotread it, knows what it is about.

Univ. is “persons”;m= persons who have read the letter;x= the Class of Johns;y= persons who know what the letter is about.

i.e. No one, but John, knows what the letter is about.

3.Those who are not old like walking;You and I are young.

Univ. is “persons”;m= old;x= persons who like walking;y= you and I.

i.e. You and I like walking.

4.Your course is always honest;Your course is always the best policy.

Univ. is “courses”;m= your;x= honest;y= courses which are the best policy.

i.e. Honesty is sometimes the best policy.

5.No fat creatures run well;Some greyhounds run well.

Univ. is “creatures”;m= creatures that run well;x= fat;y= greyhounds.

i.e. Some greyhounds are not fat.

pg1406.Some, who deserve the fair, get their deserts;None but the brave deserve the fair.

Univ. is “persons”;m= persons who deserve the fair;x= persons who get their deserts;y= brave.

i.e. Some brave persons get their deserts.

7.Some Jews are rich;All Esquimaux are Gentiles.

Univ. is “persons”;m= Jews;x= rich;y= Esquimaux.

i.e. Some rich persons are not Esquimaux.

8.Sugar-plums are sweet;Some sweet things are liked by children.

Univ. is “things”;m= sweet;x= sugar-plums;y= things that are liked by children.

There is no Conclusion.

9.John is in the house;Everybody in the house is ill.

Univ. is “persons”;m= persons in the house;x= the Class of Johns;y= ill.

i.e. John is ill.

pg14110.Umbrellas are useful on a journey;What is useless on a journey should be left behind.

Univ. is “things”;m= useful on a journey;x= umbrellas;y= things that should be left behind.

i.e. Some things, that are not umbrellas, should be left behind on a journey.

11.Audible music causes vibration in the air;Inaudible music is not worth paying for.

Univ. is “music”;m= audible;x= music that causes vibration in the air;y= worth paying for.

i.e. No music is worth paying for, unless it causes vibration in the air.

12.Some holidays are rainy;Rainy days are tiresome.

Univ. is “days”;m= rainy;x= holidays;y= tiresome.

i.e. Some holidays are tiresome.

Somexarem; Nomarey′. Somexarey.

Allxarem; Noyarem′. Noyarex′.

Somexarem′; Ally′arem. Somexarey.

Allxarem; Noyarem. Allxarey′.

Somem′arex′; Nom′arey. Somex′arey′.

Nox′arem; Allyarem′. Allyarex.

Somem′arex′; Ally′arem′. Somex′arey′.

Nom′arex′; Ally′arem′. Ally′arex.

Somemarex′; Nomarey. Somex′arey′.

Allm′arex′; Allmarey. Someyarex′.

No doctors are enthusiastic;You are enthusiastic.You are not a doctor.

Univ. “persons”;m= enthusiastic;x= doctors;y= you.

Hence proposed Conclusion is right.

All dictionaries are useful;Useful books are valuable.Dictionaries are valuable.

Univ. “books”;m= useful;x= dictionaries;y= valuable.

Hence proposed Conclusion is right.

No misers are unselfish;None but misers save egg-shells.No unselfish people save egg-shells.

Univ. “people”;m= misers;x= selfish;y= people who save egg-shells.

Hence proposed Conclusion is right.

Some epicures are ungenerous;All my uncles are generous.My uncles are not epicures.

Univ. “persons”;m= generous;x= epicures;y= my uncles.

Hence proposed Conclusion is wrong, the right one being “Some epicures are not uncles of mine.”

Gold is heavy;Nothing but gold will silence him.Nothing light will silence him.

Univ. “things”;m= gold;x= heavy;y= able to silence him.

Hence proposed Conclusion is right.

Some healthy people are fat;No unhealthy people are strong.Some fat people are not strong.

Univ. “persons”;m= healthy;x= fat;y= strong.

1.mx′0†m′1y′0¶x′y′0[Fig. I.i.e. “Nox′arey′.”

2.m′x0†m′y′1¶x′y′1[Fig. II.i.e. “Somex′arey′.”

3.m′1x′0†m′1y0¶xy′1[Fig. III.i.e. “Somexarey′.”

4.x′m′0†y′1m′0¶ nothing.[Fallacy of Like Eliminands not asserted to exist.]

5.mx′1†ym0¶x′y′1[Fig. II.i.e. “Somex′arey′.”

6.x′m0†my0¶ nothing.[Fallacy of Like Eliminands not asserted to exist.]

7.mx′0†y′m1¶xy′1[Fig. II.i.e. “Somexarey′.”

8.m′1x0†m′y0¶x′y′1[Fig. III.i.e. “Somex′arey′.”

9.x′m′1†my0¶ nothing.[Fallacy of Unlike Eliminands with an Entity-Premiss.]

10.x1m′0†y′1m0¶x1y′0†y′1x0[Fig. I (β).i.e. “Allxarey, and ally′arex′.”

11.mx0†y′1m0¶ nothing.[Fallacy of Like Eliminands not asserted to exist.]

12.xm0†y1m′0¶y1x0[Fig. I (α).i.e. “Allyarex′.”

13.m′1x′0†ym0¶x′y0[Fig. I.i.e. “Nox′arey.”

14.m1x′0†m′1y′0¶x′y′0[Fig. I.i.e. “Nox′arey′.”

15.xm0†m′y0¶xy0[Fig. I.i.e. “Noxarey.”

16.x1m0†y1m′0¶ (x1y0†y1x0)                 [Fig. I (β).i.e. “Allxarey′and allyarex′.”

17.xm0†m′1y′0¶xy′0[Fig. I.i.e. “Noxarey′.”

18.xm′0†my0¶xy0[Fig. I.i.e. “Noxarey.”

19.m1x′0†m1y0¶xy′1[Fig. III.i.e. “Somexarey′.”

20.mx0†m′1y′0¶xy′0[Fig. I.i.e. “Noxarey′.”

21.x1m′0†m′y1¶x′y1[Fig. II.i.e. “Somex′arey.”

22.xm1†y1m′0¶ nothing.[Fallacy of Unlike Eliminands with an Entity-Premiss.]

23.m1x′0†ym1¶xy1[Fig. II.i.e. “Somexarey.”

24.xm0†y1m′0¶y1x0[Fig. I (α).i.e. “Allyarex′.”

25.mx′1†my′0¶x′y1[Fig. II.i.e. “Somex′arey.”

26.mx′0†y1m′0¶y1x′0[Fig. I (α).i.e. “Allyarex.”

27.x1m0†y′1m′0¶ (x1y′0†y′1x0)                 [Fig. I (β).i.e. “Allxarey, and ally′arex′.”

28.m1x0†my1¶x′y1[Fig. II.i.e. “Somex′arey.”

29.mx0†y1m0¶ nothing.[Fallacy of Like Eliminands not asserted to exist.]

30.x1m0†ym1¶x′y1[Fig. II.i.e. “Someyarex′.”

31.x1m′0†y1m′0¶ nothing.[Fallacy of Like Eliminands not asserted to exist.]

pg14732.xm′0†m1y′0¶xy′0[Fig. I.i.e. “Noxarey′.”

33.mx0†my0¶ nothing.[Fallacy of Like Eliminands not asserted to exist.]

34.mx′0†ym1¶xy1[Fig. II.i.e. “Somexarey.”

35.mx0†y1m′0¶y1x0[Fig. I (α).i.e. “Allyarex′.”

36.m1x0†ym1¶x′y1[Fig. II.i.e. “Somex′arey.”

37.m1x′0†ym0¶xy′1[Fig. III.i.e. “Somexarey′.”

38.mx0†m′y0¶xy0[Fig. I.i.e. “Noxarey.”

39.mx′1†my0¶x′y′1[Fig. II.i.e. “Somex′arey′.”

40.x′m0†y′1m′0¶y′1x′0[Fig. I (α).i.e. “Ally′arex.”

41.x1m0†ym′0¶x1y0[Fig. I (α).i.e. “Allxarey′.”

42.m′x0†ym0¶xy0[Fig. I.i.e. “Noxarey.”

13.No Frenchmen like plumpudding;All Englishmen like plumpudding.

Univ. “men”;m= liking plumpudding;x= French;y= English.

xm0†y1m′0¶y1x0[Fig. I (α).

i.e. Englishmen are not Frenchmen.

14.No portrait of a lady, that makes her simper or scowl, is satisfactory;No photograph of a lady ever fails to make her simper or scowl.

Univ. “portraits of ladies”;m= making the subject simper or scowl;x= satisfactory;y= photographic.

mx0†ym′0¶xy0[Fig. I.

i.e. No photograph of a lady is satisfactory.

15.All pale people are phlegmatic;No one looks poetical unless he is pale.

Univ. “people”;m= pale;x= phlegmatic;y= looking poetical.

m1x′0†m′y0¶x′y0[Fig. I.

i.e. No one looks poetical unless he is phlegmatic.

16.No old misers are cheerful;Some old misers are thin.

Univ. “persons”;m= old misers;x= cheerful;y= thin.

mx0†my1¶x′y1[Fig. II.

i.e. Some thin persons are not cheerful.

17.No one, who exercises self-control, fails to keep his temper;Some judges lose their tempers.

Univ. “persons”;m= keeping their tempers;x= exercising self-control;y= judges.

xm′0†ym′1¶x′y1[Fig. II.

i.e. Some judges do not exercise self-control.

pg14818.All pigs are fat;Nothing that is fed on barley-water is fat.

Univ. is “things”;m= fat;x= pigs;y= fed on barley-water.

x1m′0†ym0¶x1y0[Fig. I (α).

i.e. Pigs are not fed on barley-water.

19.All rabbits, that are not greedy, are black;No old rabbits are free from greediness.

Univ. is “rabbits”;m= greedy;x= black;y= old.

m′1x′0†ym′0¶xy′1[Fig. III.

i.e. Some black rabbits are not old.

20.Some pictures are not first attempts;No first attempts are really good.

Univ. is “things”;m= first attempts;x= pictures;y= really good.

xm′1†my0¶ nothing.

[Fallacy of Unlike Eliminands with an Entity-Premiss.]

21.I never neglect important business;Your business is unimportant.

Univ. is “business”;m= important;x= neglected by me;y= your.

mx0†y1m0¶ nothing.

[Fallacy of Like Eliminands not asserted to exist.]

22.Some lessons are difficult;What is difficult needs attention.

Univ. is “things”;m= difficult;x= lessons;y= needing attention.

xm1†m1y′0¶xy1[Fig. II.

i.e. Some lessons need attention.

23.All clever people are popular;All obliging people are popular.

Univ. is “people”;m= popular;x= clever;y= obliging.

x1m′0†y1m′0¶ nothing.

[Fallacy of Like Eliminands not asserted to exist.]

24.Thoughtless people do mischief;No thoughtful person forgets a promise.

Univ. is “persons”;m= thoughtful;x= mischievous;y= forgetful of promises.

m′1x′0†my0¶x′y0

i.e. No one, who forgets a promise, fails to do mischief.

1.xm1†my′0¶xy1[Fig. II.]         Concl. right.

2.x1m′0†ym′0Fallacy of Like Eliminands not asserted to exist.

3.xm′1†y′1m′0¶xy1[Fig. II.]         Concl. right.

pg1494.x1m′0†ym0¶x1y0[Fig. I (α).]         Concl. right.

5.m′x′1†m′y0¶x′y′1[Fig. II.]         Concl. right.

6.x′m0†y1m0Fallacy of Like Eliminands not asserted to exist.

7.m′x′1†y′1m0Fallacy of Unlike Eliminands with an Entity-Premiss.

8.m′x′0†y′1m0¶y′1x′0[Fig. I (α).]         Concl. right.

9.mx′1†my0¶x′y′1[Fig. II.]         Concl. right.

10.m′1x0†m′1y′0¶x′y1[Fig. III.]         Concl. right.

11.x1m0†ym1¶x′y1[Fig. II.]         Concl. right.

12.xm0†m′y′0¶xy′0[Fig. I.]         Concl. right.

13.xm0†y′1m′0¶y′1x0[Fig. I (α).]         Concl. right.

14.m′1x0†m′1y′0¶x′y1[Fig. III.]         Concl. right.

15.mx′1†y1m0¶x′y′1[Fig. II.]         Concl. right.

16.x′m0†y′1m0Fallacy of Like Eliminands not asserted to exist.

17.m′x0†m′1y0¶x′y′1[Fig. III.]         Concl. right.

18.x′m0†my1¶xy1[Fig. II.]         Concl. right.

19.mx′1†m1y′0¶x′y1[Fig. II.]         Concl. right.

20.x′m′0†m′y′1¶xy′1[Fig. II.]         Concl. right.

21.mx0†m1y0¶x′y′1[Fig. III.]         Concl. right.

22.x′1m′0†ym′1¶xy1[Fig. II.]         Concl. wrong: the right one is “Somexarey.”

23.m1x′0†m′y′0¶x′y′0[Fig. I.]         Concl. right.

24.x1m0†m′1y′0¶x1y′0[Fig. I (α).]         Concl. right.

25.xm′0†m1y′0¶xy′0[Fig. I.]         Concl. right.

26.m1x0†y1m′0¶y1x0[Fig. I (α).]         Concl. right.

27.x1m′0†my′0¶x1y′0[Fig. I (α).]         Concl. right.

28.x1m′0†y′m′0Fallacy of Like Eliminands not asserted to exist.

29.x′m0†m′y′0¶x′y′0[Fig. I.]         Concl. right.

30.x1m′0†m1y0¶x1y0[Fig. I (α).]         Concl. right.

31.x′1m0†y′m′0¶x′1y′0[Fig. I (α).]         Concl. right.

32.xm0†y′m′0¶xy′0[Fig. I.]         Concl. right.

33.m1x0†y′1m′0¶y′1x0[Fig. I (α).]         Concl. right.

34.x1m0†ym′1Fallacy of Unlike Eliminands with an Entity-Premiss.

35.xm1†m1y′0¶xy1[Fig. II.]         Concl. right.

36.m1x0†y1m′0¶y1x0[Fig. I (α).]         Concl. right.

37.mx′0†m1y0¶xy′1[Fig. III.]         Concl. right.

38.xm0†my′0Fallacy of Like Eliminands not asserted to exist.

39.mx0†my′1¶x′y′1[Fig. II.]         Concl. right.

40.mx′0†ym1¶xy1[Fig. II.]         Concl. right.

1.No doctors are enthusiastic;You are enthusiastic.You are not a doctor.

Univ. “persons”;m= enthusiastic;x= doctors;y= you.

xm0†y1m′0¶y1x0[Fig. I (α).

Conclusion right.

2.Dictionaries are useful;Useful books are valuable.Dictionaries are valuable.

Univ. “books”;m= useful;x= dictionaries;y= valuable.

x1m′0†m1y′0¶x1y′0[Fig. I (α).

Conclusion right.

3.No misers are unselfish;None but misers save egg-shells.No unselfish people save egg-shells.

Univ. “people”;m= misers;x= selfish;y= people who save egg-shells.

mx′0†m′y0¶x′y0[Fig. I.

Conclusion right.

4.Some epicures are ungenerous;All my uncles are generous.My uncles are not epicures.

Univ. “persons”;m= generous;x= epicures;y= my uncles.

xm′1†y1m′0¶xy′1[Fig. II.

Conclusion wrong: right one is “Some epicures are not uncles of mine.”

5.Gold is heavy;Nothing but gold will silence him.Nothing light will silence him.

Univ. “things”;m= gold;x= heavy;y= able to silence him.

m1x′0†m′y0¶x′y0[Fig. I.

Conclusion right.

6.Some healthy people are fat;No unhealthy people are strong.Some fat people are not strong.

Univ. “people”;m= healthy;x= fat;y= strong.

mx1†m′y0

No Conclusion. [Fallacy of Unlike Eliminands with an Entity-Premiss.]

7.I saw it in a newspaper;All newspapers tell lies.It was a lie.

Univ. “publications”;m= newspapers;x= publications in which I saw it;y= telling lies.

x1m′0†m1y′0¶x1y′0[Fig. I (α).

Conclusion wrong: right one is “The publication, in which I saw it, tells lies.”

pg1518.Some cravats are not artistic;I admire anything artistic.There are some cravats that I do not admire.

Univ. “things”;m= artistic;x= cravats;y= things that I admire.

xm1†m1y0

No Conclusion. [Fallacy of Unlike Eliminands with an Entity-Premiss.]

9.His songs never last an hour.A song, that lasts an hour, is tedious.His songs are never tedious.

Univ. “songs”;m= lasting an hour;x= his;y= tedious.

x1m0†m1y′0¶x′y1[Fig. III.

Conclusion wrong: right one is “Some tedious songs are not his.”

10.Some candles give very little light;Candles are meant to give light.Some things, that are meant to give light, give very little.

Univ. “things”;m= candles;x= giving &c.;y= meant &c.

mx1†m1y′0¶xy1[Fig. II.

Conclusion right.

11.All, who are anxious to learn, work hard.Some of these boys work hard.Some of these boys are anxious to learn.

Univ. “persons”;m= hard-working;x= anxious to learn;y= these boys.

x1m′0†ym1

No Conclusion. [Fallacy of Unlike Eliminands with an Entity-Premiss.]

12.All lions are fierce;Some lions do not drink coffee.Some creatures that drink coffee are not fierce.

Univ. “creatures”;m= lions;x= fierce;y= creatures that drink coffee.

m1x′0†my′1¶xy′1[Fig. II.

Conclusion wrong: right one is “Some fierce creatures do not drink coffee.”

13.No misers are generous;Some old men are ungenerous.Some old men are misers.

Univ. “persons”;m= generous;x= misers;y= old men.

xm0†ym′1

No Conclusion. [Fallacy of Unlike Eliminands with an Entity-Premiss.]

14.No fossil can be crossed in love;An oyster may be crossed in love.Oysters are not fossils.

Univ. “things”;m= things that can be crossed in love;x= fossils;y= oysters.

xm0†y1m′0¶y1x0[Fig. I (α).

Conclusion right.

pg15215.All uneducated people are shallow;Students are all educated.No students are shallow.

Univ. “people”;m= educated;x= shallow;y= students.

m′1x′0†y1m′0¶xy′1[Fig. III.

Conclusion wrong: right one is “Some shallow people are not students.”

16.All young lambs jump;No young animals are healthy, unless they jump.All young lambs are healthy.

Univ. “young animals”;m= young animals that jump;x= lambs;y= healthy.

x1m′0†m′y0

No Conclusion. [Fallacy of Like Eliminands not asserted to exist.]

17.Ill-managed business is unprofitable;Railways are never ill-managed.All railways are profitable.

Univ. “business”;m= ill-managed;x= profitable;y= railways.

m1x0†y1m0¶x′y′1[Fig. III.

Conclusion wrong: right one is “Some business, other than railways, is profitable.”

18.No Professors are ignorant;All ignorant people are vain.No Professors are vain.

Univ. “people”;m= ignorant;x= Professors;y= vain.

xm0†m1y′0¶x′y1[Fig. III.

Conclusion wrong: right one is “Some vain persons are not Professors.”

19.A prudent man shuns hyænas.No banker is imprudent.No banker fails to shun hyænas.

Univ. “men”;m= prudent;x= shunning hyænas;y= bankers.

m1x′0†ym′0¶x′y0[Fig. I.

Conclusion right.

20.All wasps are unfriendly;No puppies are unfriendly.No puppies are wasps.

Univ. “creatures”;m= friendly;x= wasps;y= puppies.

x1m0†ym′0¶x1y0[Fig. I (α).

Conclusion incomplete: complete one is “Wasps are not puppies”.

21.No Jews are honest;Some Gentiles are rich.Some rich people are dishonest.

Univ. “persons”;m= Jews;x= honest;y= rich.

mx0†m′y1

No Conclusion. [Fallacy of Unlike Eliminands with an Entity-Premiss.]

pg15322.No idlers win fame;Some painters are not idle.Some painters win fame.

Univ. “persons”;m= idlers;x= persons who win fame;y= painters.

mx0†ym′1

No Conclusion. [Fallacy of Unlike Eliminands with an Entity-Premiss.]

23.No monkeys are soldiers;All monkeys are mischievous.Some mischievous creatures are not soldiers.

Univ. “creatures”;m= monkeys;x= soldiers;y= mischievous.

mx0†m1y′0¶x′y1[Fig. III.

Conclusion right.

24.All these bonbons are chocolate-creams;All these bonbons are delicious.Chocolate-creams are delicious.

Univ. “food”;m= these bonbons;x= chocolate-creams;y= delicious.

m1x′0†m1y′0¶xy1[Fig. III.

Conclusion wrong, being in excess of the right one, which is “Some chocolate-creams are delicious.”

25.No muffins are wholesome;All buns are unwholesome.Buns are not muffins.

Univ. “food”;m= wholesome;x= muffins;y= buns.

xm0†y1m0

No Conclusion. [Fallacy of Like Eliminands not asserted to exist.]

26.Some unauthorised reports are false;All authorised reports are trustworthy.Some false reports are not trustworthy.

Univ. “reports”;m= authorised;x= true;y= trustworthy.

m′x′1†m1y′0

No Conclusion. [Fallacy of Unlike Eliminands with an Entity-Premiss.]

27.Some pillows are soft;No pokers are soft.Some pokers are not pillows.

Univ. “things”;m= soft;x= pillows;y= pokers.

xm1†ym0¶xy′1[Fig. II.

Conclusion wrong: right one is “Some pillows are not pokers.”

28.Improbable stories are not easily believed;None of his stories are probable.None of his stories are easily believed.

Univ. “stories”;m= probable;x= easily believed;y= his.

m′1x0†ym0¶xy0[Fig. I.

Conclusion right.

pg15429.No thieves are honest;Some dishonest people are found out.Some thieves are found out.

Univ. “people”;m= honest;x= thieves;y= found out.

xm0†m′y1

No Conclusion. [Fallacy of Unlike Eliminands with an Entity-Premiss.]

30.No muffins are wholesome;All puffy food is unwholesome.All muffins are puffy.

Univ. is “food”;m= wholesome;x= muffins;y= puffy.

xm0†y1m0

No Conclusion. [Fallacy of Like Eliminands not asserted to exist.]

31.No birds, except peacocks, are proud of their tails;Some birds, that are proud of their tails, cannot sing.Some peacocks cannot sing.

Univ. “birds”;m= proud of their tails;x= peacocks;y= birds that cannot sing.

x′m0†my′1¶xy′1[Fig. II.

Conclusion right.

32.Warmth relieves pain;Nothing, that does not relieve pain, is useful in toothache.Warmth is useful in toothache.

Univ. “applications”;m= relieving pain;x= warmth;y= useful in toothache.

x1m′0†m′y0

No Conclusion. [Fallacy of Like Eliminands not asserted to exist.]

33.No bankrupts are rich;Some merchants are not bankrupts.Some merchants are rich.

Univ. “persons”;m= bankrupts;x= rich;y= merchants.

mx0†ym′1

No Conclusion. [Fallacy of Unlike Eliminands with an Entity-Premiss.]

34.Bores are dreaded;No bore is ever begged to prolong his visit.No one, who is dreaded, is ever begged to prolong his visit.

Univ. “persons”;m= bores;x= dreaded;y= begged to prolong their visits.

m1x′0†my0¶xy′1[Fig. III.

Conclusion wrong: the right one is “Some dreaded persons are not begged to prolong their visits.”

35.All wise men walk on their feet;All unwise men walk on their hands.No man walks on both.

Univ. “men”;m= wise;x= walking on their feet;y= walking on their hands.

m1x′0†m′1y′0¶x′y′0[Fig. I.

Conclusion wrong: right one is “No man walks on neither.”

pg15536.No wheelbarrows are comfortable;No uncomfortable vehicles are popular.No wheelbarrows are popular.

Univ. “vehicles”;m= comfortable;x= wheelbarrows;y= popular.

xm0†m′x0¶xy0[Fig. I.

Conclusion right.

37.No frogs are poetical;Some ducks are unpoetical.Some ducks are not frogs.

Univ. “creatures”;m= poetical;x= frogs;y= ducks.

xm0†ym′1

No Conclusion. [Fallacy of Unlike Eliminands with an Entity-Premiss.]

38.No emperors are dentists;All dentists are dreaded by children.No emperors are dreaded by children.

Univ. “persons”;m= dentists;x= emperors;y= dreaded by children.

xm0†m1y′0¶x′y1[Fig. III.

Conclusion wrong: right one is “Some persons, dreaded by children, are not emperors.”

39.Sugar is sweet;Salt is not sweet.Salt is not sugar.

Univ. “things”;m= sweet;x= sugar;y= salt.

x1m′0†y1m0¶ (x1y0†y1x0)         [Fig. I (β).

Conclusion incomplete: omitted portion is “Sugar is not salt.”

40.Every eagle can fly;Some pigs cannot fly.Some pigs are not eagles.

Univ. “creatures”;m= creatures that can fly;x= eagles;y= pigs.

x1m′0†ym′1¶x′y1[Fig. II.

Conclusion right.

1.1cd0†2a1d′0†3b1c′0;1cd†2ad′†3bc′¶ab0†a1†b1i.e. ¶a1b0†b1a0

2.1d1b′0†2ac′0†3bc0;1db′†3bc†2ac′¶da0†d1i.e. ¶d1a0

3.1ba0†2cd′0†3d1b′0;1ba†3db′†2cd′¶ac0

4.1bc0†2a1b′0†3c′d0;1bc†2ab′†3c′d¶ad0†a1i.e. ¶a1d0


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