First, it is most important to realize that Swift most emphatically does not believe in the "modest" proposal his clueless narrator makes about eating the children of the poor. He creates a tone-deaf, morally obtuse persona as his narrator, a man who is so concerned about money and economics that he completely loses sight of the fact that the salable commodities he is talking about are human beings.
To the clueless narrator, however, six advantages to having the poor fatten and sell their children as delicacies at age one for the rich to eat are as follows:
It will reduce the number of papists in Ireland.
It will make the poor self-sufficient so that they don't have to starve, beg, or sell themselves into servitude.
It will increase the wealth circulating in Ireland.
Parents will no longer have to worry about how much it costs to raises these children after their first year.
It will make men kinder to their wives, as they won't want to damage the "merchandise" the women are carrying while...
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