Drexel dragonThe Math ForumDonate to the Math Forum



Search All of the Math Forum:

Views expressed in these public forums are not endorsed by Drexel University or The Math Forum.


Math Forum » Discussions » sci.math.* » sci.math

Topic: universal quantification vs existential quantifier
Replies: 2   Last Post: Jul 27, 2013 11:29 PM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
何少仪

Posts: 6
Registered: 7/21/13
universal quantification vs existential quantifier
Posted: Jul 27, 2013 10:32 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

if set S(X) is 'x is the class's student',C(x) is 'x has learned math'?

so we cannot use ?x(S(x)->C(x)) (domain: x is all people) shows some students of class have learned math. because S(x) is false (x is not the class's student),S(x)->C(x) is true.

but why can i use ?x(S(x)->C(x)) (domain: x is all people) shows all the class's student have learned math,
beacuse S(x) is false (x is not the class's student),S(x)->C(x) is also true?





Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© Drexel University 1994-2014. All Rights Reserved.
The Math Forum is a research and educational enterprise of the Drexel University School of Education.