If I am making a truth tree and already working on two branches when I come across a double negation (eg. ~~A), do I just decompose it to A right where it is, or do I add A to all branches? Hope I'm making sense.

  • NO; the rules have to be applied one by one to every single branch. Thus, you can add A to every branch where ~~A occurs. – Mauro ALLEGRANZA Apr 19 '17 at 5:58
  • So if there's a branch without ~~A, I don't add A to it, right? – Ussurij Apr 19 '17 at 9:14
  • Exactly......... – Mauro ALLEGRANZA Apr 19 '17 at 9:26

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.