Section 1.3 Quantifiers, Predicates, and Validity
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c. Only bears are hungry.
d. If all wolves are hungry, so are bears.
e. Some animals are hungry bears.
f. Bears are hungry but some wolves are not.
g. If wolves and bears are hungry, so are all animals.
h. Some wolves are hungry but not every animal is hungry.
17. Using the predicate symbols shown and appropriate quantifiers, write each English language statement as
a predicate wff. (The domain is the whole world.)
P(x): x is a person
T(x): x is a time
F(x, y): x is fooled at y
a. You can fool some of the people all of the time.
b. You can fool all of the people some of the time.
c. You can’t fool all of the people all of the time.
18. Using the predicate symbols shown and appropriate quantifiers, write each English language statement as
a predicate wff. (The domain is the whole world.)
L(x): x is a lion
R(x): x roars
P(x): x is a predator
Z(x): x is a zebra
E(x, y): x eats y
a. All lions are predators.
b. Some lions roar.
c. Only lions roar.
d. Some lions eat all zebras.
e. All lions eat all zebras.
19. Using the predicate symbols shown and appropriate quantifiers, write each English language statement as
a predicate wff. (The domain is the whole world.)
G(x): x is a game
M(x): x is a movie
F(x, y): x is more fun than y
a. Any movie is more fun than any game.
b. No game is more fun than every movie.
c. Only games are more fun than movies.
d. All games are more fun than some movie.
20. Using the predicate symbols shown and appropriate quantifiers, write each English language statement as
a predicate wff. (The domain is the whole world.)
C(x): x is a child
T(x): x is a toy