To install click the Add extension button. That's it.

The source code for the WIKI 2 extension is being checked by specialists of the Mozilla Foundation, Google, and Apple. You could also do it yourself at any point in time.

Kelly Slayton
Congratulations on this excellent venture… what a great idea!
Alexander Grigorievskiy
I use WIKI 2 every day and almost forgot how the original Wikipedia looks like.
Live Statistics
English Articles
Improved in 24 Hours
Added in 24 Hours
Show all languages
What we do. Every page goes through several hundred of perfecting techniques; in live mode. Quite the same Wikipedia. Just better.

Conjunction introduction

From Wikipedia, the free encyclopedia

Conjunction introduction (often abbreviated simply as conjunction and also called and introduction)[1][2][3] is a valid rule of inference of propositional logic. The rule makes it possible to introduce a conjunction into a logical proof. It is the inference that if the proposition p is true, and proposition q is true, then the logical conjunction of the two propositions p and q is true. For example, if it is true that "it's raining", and it is true that "I'm inside", then it is true that "it's raining and I'm inside". The rule can be stated:

where the rule is that wherever an instance of "" and "" appear on lines of a proof, a "" can be placed on a subsequent line.

YouTube Encyclopedic

  • 1/3
    4 819
    3 750
    4 694
  • Logic 101 (#33): Conjunction Introduction
  • Introduction to Conjunctions
  • Rules 2 and 3 Conjunction


Formal notation

The conjunction introduction rule may be written in sequent notation:

where and are propositions expressed in some formal system, and is a metalogical symbol meaning that is a syntactic consequence if and are each on lines of a proof in some logical system;


  1. ^ Hurley, Patrick (1991). A Concise Introduction to Logic 4th edition. Wadsworth Publishing. pp. 346–51.
  2. ^ Copi, Irving M.; Cohen, Carl; McMahon, Kenneth (2014). Introduction to Logic (14th ed.). Pearson. pp. 370, 620. ISBN 978-1-292-02482-0.
  3. ^ Moore and Parker[full citation needed]
This page was last edited on 16 December 2020, at 19:47
Basis of this page is in Wikipedia. Text is available under the CC BY-SA 3.0 Unported License. Non-text media are available under their specified licenses. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc. WIKI 2 is an independent company and has no affiliation with Wikimedia Foundation.