The detractors of the theatre are often expert in persuasive half-truths and masters of dialectic sleight-of-hand. Their performances are often so adroit that the spectator is quick to believe that the trunk is really empty, yet the false bottom is there for all its cunning concealment. Take, for example, George Moore, in the preface to his last play, “The Coming of Gabrielle.” “The illusion created by externals, scenes, costumes, lighting and short sentences is in itself illusory,” he professes to believe, though why he numbers the dramatist’s short sentences among the externals of the stage is not quite clear. “The best performances of plays and operas are witnessed at rehearsals. Jean de Reszke was never so like Tristan at night as he was in the afternoon when he sang the part in a short jacket, a bowler hat and an umbrella in his hand. The chain armour and the plumes that he wore at night were but a distraction, setting our thoughts on periods, on the short swords in use in the ninth century in Ireland or in Cornwall, on the comfort or the discomfort of the ships in which the lovers were voyaging, on the absurd night-dress which is the convention that Isolde should appear in, a garment she never wore and which we know to be make-believe. But the hat and feathers that Isolde appears in when she rehearses the part are forgotten the moment she sings; and if I had to choose to see Forbes-Robertson play Hamlet or rehearse Hamlet, I should not hesitate for a moment. The moment he speaks he ceases to be a modern man, but in black hose the illusion ceases, for we forget the Prince of Denmark and remember the mummer.” Years ago, in a volume of critical essays given the title “Another Book on the Theatre,” I took a boyish delight in setting off precisely the same noisy firework just to hear the folks in the piazza rocking-chairs let out a yell. These half-truths serve criticism as sauce serves asparagus: they give tang to what is otherwise often tasteless food. This is particularly true with criticism at its most geometrical and profound, since such criticism, save in rare instances, is not especially lively reading. But, nevertheless, the sauce is not the asparagus. And when Mr. Moore (doubtless with his tongue in his cheek) observes that he can much more readily imagine the lusty Frau Tillie Pfirsich-Melba as Isolde in a pink and green ostrich feather hat confected in some Friedrichstrasse atelier than in the customary stage trappings, he allows, by implication, that he might even more readily imagine the elephantine lady as the seductive Carmen if she had no clothes on at all.