Results 1 to 7 of 7

Math Help - Mathematical Logic by Cori and Lascar : Possible typo?

  1. #1
    Newbie
    Joined
    Jun 2011
    Posts
    10

    Mathematical Logic by Cori and Lascar : Possible typo?

    I have a question on the textbook "Mathematical Logic: Propositional calculus, Boolean Algebras, predicate calculus" by Rene Cori and Daniel Lascar.

    On Lemma 1.6 on this page there is a part that says,
    "...if \mathcal{Y}(W) and \mathcal{Y}(V) are true, then \mathcal{Y}(\neg F), \mathcal{Y}(F \wedge G), \mathcal{Y}(F \vee G), \mathcal{Y}(F \Rightarrow G), \mathcal{Y}(F \Leftrightarrow G) are also true.".

    I think there is a typo there and it should be,
    "...if \mathcal{Y}(W) and \mathcal{Y}(V) are true, then \mathcal{Y}(\neg W), \mathcal{Y}((W \wedge V)), \mathcal{Y}((W \vee V)), \mathcal{Y}((W \Rightarrow V)), \mathcal{Y}((W \Leftrightarrow V)) are also true.",
    WITH THE ADDITION OF THE EXTRA PARENTHESES.

    I tried to attach a picture from the next page of the rest of the proof, because that might help, and the google books omits that page. But it doesn't upload. I don't know why. Size is 33kB.

    Propositional Formulas are defined in Definition 1.2 on this page.

    Is this a typo is there something I don't understand?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Senior Member
    Joined
    Feb 2010
    Posts
    466
    Thanks
    4
    Delete post.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Jun 2011
    Posts
    10
    I uploaded the rest of the proof to photobucket. It's here.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor
    Joined
    Oct 2009
    Posts
    5,561
    Thanks
    785
    Is this a typo is there something I don't understand?
    I think you are right on both counts: it should use W and V and add parentheses.
    Follow Math Help Forum on Facebook and Google+

  5. #5
    Newbie
    Joined
    Jun 2011
    Posts
    10
    Thanks. I could not overlook the possibility that I might be wrong.
    Follow Math Help Forum on Facebook and Google+

  6. #6
    Senior Member
    Joined
    Feb 2010
    Posts
    466
    Thanks
    4
    The book stipulates the convention that outer parentheses on formulas may be dropped to stand for the actual formula with outer parenetheses.
    Follow Math Help Forum on Facebook and Google+

  7. #7
    Newbie
    Joined
    Jun 2011
    Posts
    10
    Quote Originally Posted by MoeBlee View Post
    The book stipulates the convention that outer parentheses on formulas may be dropped to stand for the actual formula with outer parenetheses.
    That's in page 10, right. Thanks. I forgot that.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 4
    Last Post: June 3rd 2011, 09:46 AM
  2. What does N.T.A mean in mathematical logic?
    Posted in the Discrete Math Forum
    Replies: 1
    Last Post: June 1st 2010, 12:54 PM
  3. mathematical logic books
    Posted in the Discrete Math Forum
    Replies: 4
    Last Post: August 9th 2009, 11:03 AM
  4. Replies: 3
    Last Post: July 17th 2009, 11:10 AM
  5. Mathematical Logic Algorithm
    Posted in the Discrete Math Forum
    Replies: 0
    Last Post: April 7th 2009, 08:19 PM

/mathhelpforum @mathhelpforum