This ballads was composed between 1797 and 1798. It is the story of a crime and its punishment told by the protagonist himself, an old mariner condemned, to expiate his crime, to travel for ever from land to land telling his story and teaching, by his example, love and reverence for all God's creatures. The poem is divided into seven sections, each one ending with hint at the crime and each one constituting a new stage in the progress from crime to punishment.
According to Coleridge the imagination is divided into two types: primary and secondary. Primary imagination is "the living power and the prime agent of human perception". It is the faculty by which we perceive the world around us; it works through our senses and is common to all human beings. Secondary imagination is the poetic vision, the faculty that a poet has "to idealize and unify". During a state of ecstasy, in fact, images do not appear isolated, but associated according to laws of their own which have nothing to do with the data of experience. The imagination is contrasted with fancy, which is inferior to it, since it is a kind of mechanical and logical faculty which enables a poet to aggregate and associate metaphors, similes and other poetical devices.
They both despise Fancy and exalt the imagination but, while for W. the latter "half-creates", or rather modifies and transforms the data of experience (through "recollection in tranquillity"), lifting them above a passive "recording", for C. the imagination transcends the data of experience and "creates" in the true sense of the word. The best example of this particular conception is Kubla Khan. If compared with W.'s contribution to the Lyrical Ballads, C.'s was very small: only four poems. Yet, among them he wrote one which was to exceed the whole of W.'s in mastery of rhyme and rhythm of diction and in wealth and vividness of imagery: the rime of the ancient mariner.