more from E.J. Lemmon

### Single Idea 9509

#### [catalogued under 4. Formal Logic / B. Propositional Logic PL / 2. Tools of Propositional Logic / a. Symbols of PL]

Full Idea

If P and Q are any two propositions, the proposition that both P and Q is called the 'conjunction' of P and Q, and is written P∧Q.

Gist of Idea

That proposition that both P and Q is their 'conjunction', written P∧Q

Source

E.J. Lemmon (Beginning Logic [1965], 1.3)

Book Reference

Lemmon,E.J.: 'Beginning Logic' [Nelson 1979], p.19

A Reaction

[I use the more fashionable inverted-v '∧', rather than Lemmon's '&', which no longer seems to be used] P∧Q can also be defined as ¬(¬P∨¬Q)