Personification- where inanimate objects or abstract concepts are seemingly endowed with human self-awareness; where human thoughts, actions, perceptions and emotions are directly attributed to inanimate objects or abstract ideas.
Fitzgerald uses personification to set a sense of allure and mister y in the book, giving it a more mysterious tone.
He also uses personification to enhance the qualities of a character and give them more depth, and in this case, capture the wonder of the persona that is Gatsby; "He smiled understandingly--much more than understandingly. It was one of those rare smiles with a quality of eternal reassurance in it, that you may come across four or five times in life. It face--or seemed to face--the whole external world for an instant, and then concentrated on you with an irresistible prejudice in your favour. It understood you just as far as you wanted to be understood, believed in you as you would like to believe in yourself, and assured you that tit had precisely the impression of you that, at your best, you hoped to convey." pg 49.
One of the strongest, and most prominent examples of personification in the book is the advertisement that overlooks the ash-heaps; “..above the grey land and the spasms of bleak dust ... you perceive ... the eyes of Doctor. T.J. Eckleburg. The eyes ... are blue and gigantic -- their retinas are one yard high. They look out of no face, but, instead, from a pair of enormous yellow spectacles which pass over a nonexistent nose. ... But his eyes ... brood on over the solemn dumping ground."
The eyes reinforce the statement that Fitzgerald is making about the