What play did Shakespeare write when he wrote Twelfth Night?

During each decade of personal growth, new wonders appeared in Twelfth Night. The fact is that Twelfth Night is not simply a comedy, one that satisfies by having everything happily resolved at its end. Twelfth Night, the name we seem always to use for the play, is actually an abbreviation of the full title Shakespeare gave his work: Twelfth Night or What You Will. The first half merely identifies the occasion for which the play was penned. Although less often cited than is Jacques’ statement about the seven ages of man, Twelfth Night’s epilogue is just as explicit. Shakespeare knew so very much. He captured and expressed so very much that only slowly and partially, little by little, each of us comes to learn and appreciate for ourselves, truths intrinsic to life, discoveries made and grasped differently across our changing ages.