George Bernard Shaw is said to have told W.S.C.:
Am reserving two tickets for you for my premiere. Come and bring a friend—if you have one.
W.S.C. to G.B.S.:
Impossible to be present for the first performance. Will attend the second—if there is one.

What It Means

This is a placeholder explanation generated by the low-overhead model. It interprets "George Bernard Shaw is said to have told W.S.C.:
Am reserving two tickets for you for my premiere. Come and bring a friend—if you have one.
W.S.C. to G.B.S.:
Impossible to be present for the first performance. Will attend the second—if there is one." in the context of "(Version given in Irrepressible Churchill: A Treasury of Winston Churchill's Wit by Kay Halle, 1966)
• Apocryphal, originally featured Noël Coward and Randolph Churchill (Winston's son); attested 1946 (columnist Walter Winchell, attributed to anonymous United Press journalist in London). Originally only featured first half about lack of friend; second half (retort about lack of second performance) attested 1948, as was replacement of personages by George Bernard Shaw and Winston Churchill. Specific plays added in later variants, ranging from Man and Superman (1903) to Saint Joan (1923), and appeared in biographies and quote collections from the 1960s.
• The quote is presumably apocryphal due to earliest attestations being too different, less famous personages (easily replaced by more famous ones), the quotation becoming more elaborate in later versions, the 20+ year gap between putative utterance and first attestation, and the approximately 50 year gap between putative utterance and appearance in reference works, all as undocumented hearsay.
• Detailed discussion at "Here are Two Tickets for the Opening of My Play. Bring a Friend—If You Have One", Garson O'Toole, Quote Investigator, March 25, 2012." to mean that wisdom is timeless.