Symbolic Logic

If p stands for the statement, "All right angles are equal," and q the statement, "Parallel lines never meet," one can make a single statement by joining them with "and": "All right angles are equal and parallel lines never meet." This can be symbolized p Λ q, using the inverted V-shaped symbol to stand for the conjunction "and." Both the combined statement and the word "and" itself are called "conjunctions." In ordinary English, there are several words in addition to "and" which can used for joining two statements conjunctively, for example, "but." "But" is the preferred conjunction when one wants to alert the reader to a relationship which otherwise might seem contradictory. For example, "He is 6 ft (1.8 m) tall, but he weighs 120 lb (54 kg)." In logic the only conjunctive term is "and."