How does Irony help explain the theme of the poem Richard Cory?
The irony is at the end of the poem. The author spends the entire poem describing Richard Cory as the ideal man - that guy that everyone 'wants to be'. The peacefulness and 'perfectness' is further accentuated with language such as "calm", "quietly", "grace". It's a 'summer night', rather than a wintery storm.
The irony is 'situational', rather than 'comical' - that is, the expected ending does not eventuate. Here, the outcome, delivered bluntly in the last line of the poem, (Went home and put a bullet through his head) completely changes the situation, mood and feel of the poem.
The poem also uses 'verbal irony' - the meaning that is employed is sharply different from the meaning that is obviously expressed. Here, Richard is described as being "richer than a king". But richness in life cannot be measured individually by either happiness, or wealth. Rather, 'richness' is the result of a fulfilled life.