¶ … Man" intended to present a set of ethical and moral rules that would help a man vindicate the ways of God instead of criticizing the same. It was written in the neoclassical tradition which favored reason over blind passion and emotional restraint over Renaissance obsession with excessive expression. It is more in line with John Milton's Paradise Lost where theme and central Christian beliefs are concerned. While "Essay on man" may not be inherently Christian, it does promote ancient Christian assumption that man sinned once and the burden of that original sin stays with man throughout his life. For this reason, he needs to work even harder to exonerate himself and achieve salvation. The most controversial line in the Essay claims that "one truth is clear, 'Whatever IS, is RIGHT'" (I. 1.294). This line appears to suggest that morality and ethical rules are useless, since whatever happens for example, rape, kidnapping, killings etc. are right. But this is not exactly what Pope meant. Even though it appears controversial at first, when read in the context of the entire poem, it becomes clear that Pope only wanted to promote the neoclassical belief that man should discipline himself by exercising restraint and applying his intellectual powers. In the line as well, Pope was only advocating the reasoning that God has a master's plan according to which everything that happens in this world, happens for a reason. Pope accepts that life is not free of pain or suffering in fact he only encourages us to understand and accept God's plans as wiser and more beneficial despite all the pain we experience:

But errs not nature from this gracious end,

From burning suns when livid deaths descend,

When earthquakes swallow, or when tempest sweep

Towns to one grave, whole nations to the deep? (I. ll. 140-143)

Alexander Pope was the leading representative of the Augustan era in literature. This was the section of neoclassicist movement that started in early 1700s and ended in 1750s. Neoclassicism in literature referred to the movement that developed as a reaction...

The Renaissance writers were not concerned with the evil or negative side of nature; they presented it as something beautiful, harmonious and benevolent. However this was just one side of the picture -- the optimistic side. On the other side of the coin, nature bore an ugly face. We see people dying due to homicides, famines, wars etc. How would a Renaissance poet justify this with his overly optimistic opinion of nature? They couldn't and thus the Augustan Age appeared which is also known as the neoclassical age where poets and writers used intellect and reason to vindicate the ways of God.
Neoclassicists did not see only the 'evil side' of nature but neither were they so optimistic as to see the bright side of life only. Though Romantics were not always unreasonably positive in their outlook, in fact they had a tendency to over-romanticize every pain, sorrow and engage in self-pity and then seek nature for healing and help. However this has not been neoclassicist approach. For people like Dryden, Pope and Johnson, nature was both evil and benevolent but in both its form it was always fair and just. In other words, they meant to promote the view that Nature may be ugly or beautiful but it's never unfair. Pope understands the existence of virtue and vice as all neoclassicists did but they felt that if man used his reasoning faculty, he could see the right from the wrong and can extend the boundaries of his limitations. He felt that in God's master plan, everything has a place and a purpose to serve and so do vice and virtue: "self-love, to urge, and Reason, to restrain" (I. l54). Therefore the very typical neoclassicist reaction was neither " ... this a good nor that a bad we call" (II. l.56). He agreed that denying the existence of vice and virtue was not only wrong but also foolish: "Fools! ...who from hence into the notion fall, / That Vice or Virtue there is none at all" (II. 210-211). But neoclassicist maintained that vice and virtue, good and evil were forces that were required to maintain balance and somehow served God's purpose. He says that…