Childhood
Several of Coleridge’s poem mention childhood, whether it is a poem’s adult speaker reflecting on childhood memories (such as in “Frost at Midnight” and “Sonnet: To the River Otter”) or Coleridge’s discussion of the hopes he has for his son (such as in “Frost at Midnight” and “The Nightingale”). Coleridge’s focus on childhood revolves around an idealization of the carefree nature and innocence of childhood.
For Coleridge, childhood is the shaper of adult destiny. He finds that his own upbringing was marred by life in the city, and hopes to create a better connection between his son and the spirit of nature by raising his own child in the countryside. Childhood innocence and free-spiritedness is the hope unobtainable to Coleridge the adult, so he wishes to prolong and deepen this experience for the next generation.
Innocence
In connection with the aforementioned theme of childhood, several of Coleridge’s poems focus on innocence. In the poems in which Coleridge either speaks to of speak of his son, “Frost at Midnight” and “The Nightingale,” Coleridge expresses much happiness in the prospects of creating a nurturing and idyllic upbringing for his son. In “Christabel,” Coleridge explores the vulnerability of innocence and purity.
In Coleridge's works, innocence is not the same as ignorance, nor is it a sort of bland simplicity. His innocence is the state of being pure in one's relationship to nature and to others--to have no artificial barriers or societal constructs barring one's appreciation of the natural world. Innocence is a deep state of being, in which one's thought and emotions are unified and without the conflicts experienced by the majority of "experienced" humanity.
Man's relationship with nature
An appreciation of the marvels of nature is a constant theme that runs throughout Coleridge’s poetry. In poems such “The Nightingale” and “Dejection: An Ode,” Coleridge conveys his understanding that man and nature are separate entities, thus people should not project their own qualities onto their interpretation of nature’s qualities. In “Frost at Midnight” and “Sonnet: To the River Otter,” Coleridge describes how an intimate relationship with nature influences a child’s happiness.
The speaker's of Coleridge's poems (usually Coleridge himself) often mourn their own incomplete connection with nature. Coleridge blamed his own inability to simply enjoy nature in all her myriad forms on his youthful experience in the city, where natural beauty was rare to behold. He connects childhood innocence and a correct relationship with nature, blending them together into his other dominant theme of nostaligiac longing for a simpler, more pure past.
Dreams/Sleep
In Coleridge’s poems, sleep and dreams offer a portal to experiencing happiness and ecstasy. In “Christabel,” the title character dreams at night and has “a vision sweet”about the knight whom she will marry. In “Kubla Khan,” the dream-world of Xanadu offers fantastical features of nature such as a “sunny pleasure-dome.”
In "Frost at Midnight," Coleridge places a dream within a daydream when he turns his thoughts back to a summer childhood in the second stanza. There the child-speaker looks out his classroom windown to long for the natural world outside so long that he is lulled into a hazy daydream of running about outside even as he sits at his desk, supposedly studying, inside the school. For one brief moment, this dream allowed the young Coleridge to escape the confines of the classroom, and it is to this escape that the adult Coleridge turns in his own moment of solemn introspection in the frosty winter midnight.
Imagination
The power of the imagination is a familiar motif in several of Coleridge’s poems. In “Kubla Khan,” Coleridge explores the fantastical creations of the imagination. In “Dejection: An Ode,” Coleridge laments on the pain an artist suffers when his imagination and creativity are stifled by depression. In “Frost at Midnight,” Coleridge likewise laments the aimlessness of his thoughts of his thought and his lack of originality and creativity on the particular night of the poem’s setting.
The imagination is connected to nature and to childhood in Coleridge's works. Kubla Khan's "stately pleasure dome" is a thing of imagination, but the reader knows this primarily because it is an inconceivable juxtaposition of natural elements (caves of ice over an underground sunless sea). In "Frost at Midnight" the speaker longs for the imaginative powers of his youth, when he could sit inside a classroom on a bright, hot summer's day and imagine himself outdoors running through the countryside.
Happiness
Several of Coleridge’s poems explore the sources of happiness. In “Dejection: An Ode,” Coleridge acknowledges that he cannot solely rely on his external surroundings in nature to bring him happiness and that he must take responsibility for his emotional state. Nevertheless, in “Frost at Midnight,” “Sonnet: To the River Otter,” and “The Nightingale,” Coleridge describes how having an intimate relationship with nature can have a positive effect on one’s happiness.
Happiness is also to be found in returning to a state of childlike innocence. Gazing upon his baby in "Frost at Midnight," Coleridge is overwhelmed by the child's beauty and made dizzyingly happy. LIkewise, it is the days of his youth which make him happy in "Sonnet: To the River Otter."
Evening/Night
In the essay “Coleridge and the Scene of Lyric Description,” Christopher R. Miller notes that “Coleridge’s major lyrics are evening poems that usually mark the changes from sunset to twilight to darkness or frame themselves as solitary nocturnal vigils” (521). The poems “Frost at Midnight,” “Dejection: An Ode,” and “The Nightingale” all exemplify Miller’s observation. In all three of these poems, Coleridge observes the features of the evening or the night, while mediating on subjects such as man’s relationship with nature and the true sources of happiness.
