A Pair of Blue Eyes is a novel by Thomas Hardy, published in 1873.
The book describes the love triangle among a young woman, Elfride Swancourt, and her two suitors from very different backgrounds. Stephen Smith is a socially inferior but ambitious young man who adores her and with whom she shares a country background. Henry Knight is the respectable, established, older man who represents London society.
Elfride finds herself caught in a battle between her heart, her mind and the expectations of those around her - her parents and society. The novel is notable for the strong parallels to Hardy and his first wife Emma Gifford. When Elfride's father finds that his guest and candidate for his daughter's hand, architect's assistant Stephen Smith, is the son of a mason, he immediately orders him to leave.
This was the third of Hardy's novels to be published and the first to bear his name. The term "cliffhanger" is considered to have originated from this novel, which was first serialised in Tinsley's Magazine between September 1872 and July 1873. At one stage Hardy leaves Henry Knight literally hanging off a cliff staring into the stony eyes of a trilobite embedded in the rock.