Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Conditional rule

  1. Sep 15, 2008 #1
    what is conditional rule,how is it used in:

    1) propositional calculus

    2) IN ordinary mathematical proofs ,examples will help
  2. jcsd
  3. Sep 15, 2008 #2


    User Avatar
    Science Advisor
    Homework Helper

    In propositional calculus, A => B is equivalent to ~A v B. It's just one more of those logic operators which can be expressed in others (or: be used to express all others in). But implication is an "intuitive" rule, in the sense that it indicates something logically following from something else.

    In "ordinary" mathematical proofs, it is used all the time. Open any mathematics book and it will be full of statements like "if ..., then ...", "assuming ..., we can show ...." and "from ... it follows that ....".
  4. Sep 15, 2008 #3
    I AM sorry it was my mistake what i actually meant by conditional rule it was ;

    the rule of conditional proof ,known as the DEDUCTION THEOREM in some books

    thank you
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Conditional rule