Ducks swim?

In its traditional form “Will a duck swim?” this is one of the oldest of many popular jocular affirmative questions like “Is the Pope Catholic?” A detailed study of these “sarcastic interrogations” by Charles Clay Doyle provides the necessary background for Joyce’s version of the phrase.¹

The OED informs us that “does (or will, would) a duck swim? is “a colloquial phrase of enthusiastic acceptance or confirmation”.

The expression can be traced back to the 17th century in one of the plays of Thomas Otway, The History and fall of Caius Marius, first performed in 1680:

Lavinia. Nay pr’ythee be not angry, Nurse, I meant No ill. Speak kindly, will my Marius come?

Nurse. Will he? will a Duck swim? (Act II, Scene 2)

As P. W. Joyce in English as we speak it in Ireland and other documentary evidence confirm, the phrase was particularly common in Ireland:

A person who is offered anything he is very willing to take, or asked to do anything he is anxious to do, often answers in this way:—'James, would you take a glass of punch?' or 'Tom, will you dance with my sister in the next round?' In either case the answer is, 'Would a duck swim?'

P.W. Joyce, English as we speak it in Ireland (1910), p. 13

The Lenehanesque variant the I-narrator in Cyclops uses is more difficult to trace. It does turn up though around the time when Ulysses was written:

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