Swift uses verbal irony, stating the opposite of what he means, in order to promote his ideas on what SHOULD be done to help the poor.
Throughout the essay he poses his ridiculous ideas--eating babies--to help this cause. So when he uses verbal irony, it becomes very clear that his ACTUAL ideas are the more sensible and reasonable (and actually quite logical and simplistic as well!)
The verbal irony that outlines his actual plan is as follows:
Therefore let no man talk to me of other expedients: Of taxing our absentees at five shillings a pound: Of using neither cloaths, nor houshold furniture, except what is of our own growth and manufacture: Of utterly rejecting the materials and instruments that promote foreign luxury: Of curing the expensiveness of pride, vanity, idleness, and gaming in our women: Of introducing a vein of parsimony, prudence and temperance: Of learning to love our country, wherein we differ even from Laplanders, and the inhabitants of Topinamboo: Of quitting our animosities and factions, nor acting any longer like the Jews, who were murdering one another at the very moment their city was taken: Of being a little cautious not to sell our country and consciences for nothing: Of teaching landlords to have at least one degree of mercy towards their tenants. Lastly, of putting a spirit of honesty, industry, and skill into our shop-keepers, who, if a resolution could now be taken to buy only our native goods, would immediately unite to cheat and exact upon us in the price, the measure, and the goodness, nor could ever yet be brought to make one fair proposal of just dealing, though often and earnestly invited to it.
The key point to remember when reading Swift is that he is a master of satire. Accordingly, read everything he is writing with a grain of salt! Try to approach the text as if it were an 18th Century version of "The Colbert Report" -- start by presuming that Swift (the real, live author himself) is, in fact, well aware of the absurdity of the arguments posited by the pamphlet he presents. Like Colbert, a large chunk of Swift's argument is simply designed not so much to present a viable course of counter action, but rather to lay bare the foibles of the half-cocked theories he expounds.
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