Jonathan Swift's A Modest Proposal, first published in 1729, is a satirical essay in which the author proposes absurd solutions to the problems of overpopulation, abject poverty, and unemployment in Ireland. The absurdity of the solutions is meant to highlight the severity of the problems, as well as the ineptitude and cruel indifference of the ruling classes to those problems.
In paragraph 17, the author considers cannibalism as a viable solution to the problem of how to feed a growing population and specifically as a possible means by which to feed the lower classes. He suggests that people might be fed by or with "the bodies of young lads and maidens, not exceeding fourteen years of age." The author reasons that great numbers of children in Ireland are starving anyway and that it therefore would be efficient to use the dead bodies of those children to feed the hungry who are still alive. After putting forward this proposal, the author acknowledges that "some scrupulous people might be apt to censure such a practice." This is an example of understatement. We can reasonably assume that many more than "some scrupulous people" would object to such a proposal. The understatement here has the effect of emphasizing to the reader the cruel indifference of the upper and ruling classes to the hunger of the lower classes.
In paragraph 19, the author remarks that there are a "vast number" of poor people who are "every day dying, and rotting, by cold and famine, and filth, and vermin." The clear implication here is that at least dozens of poor people are dying every day in the most appalling and inhumane of conditions. The effect of this seeming exaggeration is to shock the reader and to suggest how bad the situation might become if no reasonable solutions are found.