Diction is the specific choice, syntax, and tone of the words that an author or poet chooses. In the case of Dylan Thomas in his poem, Do not Go Gentle Into that Good Night, the poem is structured to offer a juxtaposition of light/dark, happy/sad, which offers insight into the poet's mindset at the time. He uses diction to indicate that those who face death (as everyone does) should not face it without fighting for life. The form that Thomas uses is a villanelle, which was mostly used for poems depicting pastoral content. That he chooses this form offers, through diction, a type of irony as this is not pastoral in nature. Each stanza serves a purpose in the poem. The first stanza is a command, 2-5 are persuasive, while the 6th is directed toward his father encouraging him to fight.