Madness might be regarded as a particularly operatic condition. Irrational characters, featured in operas from the seventeenth century to the present, claim, by definition, the right to abnormal behavior; their instability legitimizes their singing. In spoken drama, the mere fact of singing was almost sufficient for a diagnosis of insanity. Ophelia's songs (Hamlet, IV, v) offer incontrovertible evidence of her dementia.
Ophelia's appearance in IV, v is prefaced by an account of her mode of speech:
She speaks much of her father, says she hears
There's tricks i' the world, and hems and beats her heart,
Spurns enviously at straws; speaks things in doubt,
That carry but half sense: her speech is nothing,
Yet the unshaped use of it doth move
The hearers to collection; they aim at it,
And botch the words up fit to their own thoughts;
Which, as her winks and nods and gestures yield them,
Indeed would make one think there might be thought,
Though nothing sure, yet much unhappily.
And Ophelia herself then proceeds to confirm the report, speaking almost entirely in songs until the end of the scene. And she kept singing until she died, according to the Queen's report to Laertes (IV, vii):
When down her weedy trophies and herself
Fell in the weeping brook. Her clothes spread wide,
And mermaid-like a while they bore her up:
Which time she chanted snatches of old tunes,
As one incapable of her own distress,
Or like a creature native and indued
Unto that element: but long it could not be
Till that her garments, heavy with their drink,
Pull'd the poor wretch from her melodious lay
To muddy death.