Amn't

As stately, plump Buck Mulligan explains to Haines,

I'm the queerest young fellow that ever you heard
My mother's a jew, my father's a bird.
With Joseph the joiner I cannot agree,
So here's to disciples and Calvary.

If anyone thinks that I amn't divine
He'll get no free drinks when I'm making the wine
But have to drink water and wish it were plain
That I make when the wine becomes water again.

Authority to reject the wretched locution, "Aren't I."

Reading James Joyce's Ulysses.