An obvious example of an obligatory scene of this class may be found in the third act of Othello.  The poet is bound to show us the process by which Iago instils his poison into Othello’s mind.  He has backed himself, so to speak, to make this process credible to us; and, by a masterpiece of dexterity and daring, he wins his wager.  Had he omitted this scene—­had he shown us Othello at one moment full of serene confidence, and at his next appearance already convinced of Desdemona’s guilt—­he would have omitted the pivot and turning—­point of the whole structure.  It may seem fantastic to conceive that any dramatist could blunder so grossly; but there are not a few plays in which we observe a scarcely less glaring hiatus.

A case in point may be found in Lord Tennyson’s Becket.  I am not one of those who hold Tennyson merely contemptible as a dramatist.  I believe that, had he taken to playwriting nearly half-a-century earlier, and studied the root principles of craftsmanship, instead of blindly accepting the Elizabethan conventions, he might have done work as fine in the mass as are the best moments of Queen Mary and Harold.  As a whole, Becket is one of his weakest productions; but the Prologue and the first act would have formed an excellent first and third act for a play of wholly different sequel, had he interposed, in a second act, the obligatory scene required to elucidate Becket’s character.  The historic and psychological problem of Thomas Becket is his startling transformation from an easy-going, luxurious, worldly statesman into a gaunt ecclesiastic, fanatically fighting for the rights of his see, of his order, and of Rome.  In any drama which professes to deal (as this does) with his whole career, the intellectual interest cannot but centre in an analysis of the forces that brought about this seeming new-birth of his soul.  It would have been open to the poet, no doubt, to take up his history at a later point, when he was already the full-fledged clerical and ultramontane.  But this Tennyson does not do.  He is at pains to present to us the magnificent Chancellor, the bosom friend of the King, and mild reprover of his vices; and then, without the smallest transition, hey presto! he is the intransigent priest, bitterly combating the Constitutions of Clarendon.  It is true that in the Prologue the poet places one or two finger-posts—­small, conventional foreshadowings of coming trouble.  For instance, the game of chess between King and Chancellor ends with a victory for Becket, who says—­

  “You see my bishop
  Hath brought your king to a standstill.  You are beaten.”

The symbolical game of chess is a well-worn dramatic device.  Becket, moreover, seems to feel some vague disquietude as to what may happen if he accepts the archbishopric; but there is nothing to show that he is conscious of any bias towards the intransigent clericalism of the later act.  The character-problem, in fact, is not only not solved, but is ignored.  The obligatory scene is skipped over, in the interval between the Prologue and the first act.