Exercises 59–62 are based on questions found in the book

Symbolic Logic by Lewis Carroll.

59. Let P (x), Q(x), and R(x) be the statements “x is a

professor,” “x is ignorant,” and “x is vain,” respectively.

Express each of these statements using quantifiers; log-

ical connectives; and P (x), Q(x), and R(x), where the

domain consists of all people.

a) No professors are ignorant.

b) All ignorant people are vain.

c) No professors are vain.

d) Does (c) follow from (a) and (b)

what is the soution of d) cause i did not understand what the d) says?