First of all I would like to describe what irony is, this techtique is employed by authors who what to expose and criticize corruption or any other topic (individual or social) by using exaggerations it is not to make people laugh but to warn people about something Swift used irony in those lines to show he incompetence of Ireland's politicians and how tyranny they could be.
The author Illustrates how the political system of Ireland works (only serving the Wealthy at the expense of the masses)
In his essay "A Modest Proposal," Swift creates a satirical proposal: he argues that poor Irish families should sell their children so that they can be eaten by rich English people. Throughout the essay, Swift tries to explain why this is a good strategy for all involved.
The social conditions in Ireland at this time were extremely bad. Poverty was rampant, and famine was common. This was the consequence, to a large extent, of the unjust policies of the English, who controlled the island. Swift emphasizes this point by highlighting how little English people seem to care about Ireland. Moreover, he blames this on the government, targeting English leaders in particular, as well as the high classes.
C. The author comes to various outlandish conclusions that lead the reader to question his credibility.