Quote 46
But I am not in the least pain upon that matter because it is very well known that they are every day dying and rotting by cold and famine, and filth and vermin, as fast as can be reasonably expected. (18)
The conditions may be slightly exaggerated, but Swift is trying to tug at the heartstrings of wealthy Irish readers.
Quote 47
For first, as I have already observed, it would greatly lessen the number of papists, with whom we are yearly overrun, being the principal breeders of the nation as well as our most dangerous enemies. (20)
Swift is satirizing English gossip that Irish Catholics would rise up and restore the Pretender to the throne.
Quote 48
I desire the reader will observe I calculate my remedy for this one individual kingdom of Ireland, and for no one that ever was, is, or, I think, ever can be upon earth. (28)
Just so we're clear, Swift isn't proposing that the whole world turn to cannibalism. Just Ireland will do for now.