In "Tonight I Can Write (The Saddest Lines)," the speaker discusses his own sadness through the lens of writing, so that the topic of writing poetry becomes a major focus of the poem itself. In the case of Neruda's poem, this metatextual tendency is part of an examination of the relationship between emotion and writing: the poem prompts us to ask whether experiencing a given feeling will make it easier or more natural for writers to express that same feeling in poetry. But Neruda is far from the first poet to insert a discussion of the writing process into a work of poetry. Some, like him, have used poems as a platform to discuss the link between inner life and linguistic expression, while yet others have explored other aspects of poetry, writer's block, and the reader-writer relationship.
Charles Bukowski's "so you want to be a writer" takes on the question of writerly identity. While Neruda's poem suggests that emotion precedes poetry, urging people towards self-expression as they seek to externalize their internal lives, Bukowski's poem works on a different set of logical principles. It treats linguistic expression as a rare but intense emotional urge in itself, rather than as a tool that can be used (with varying degrees of success), to express a wide variety of emotional experiences. To be a writer, according to this poem, is to be someone who feels a non-negotiable desire to write—about anything. Moreover, Bukowski's poem is framed as sharp, honest advice for aspiring writers. The speaker warns these would-be writers to avoid the art form unless they, too, are full of this irresistible literary urge. "unless it comes out of / your soul like a rocket, / unless being still would / drive you to madness or / suicide or murder, / don't do it," the speaker cautions.
Meanwhile, Jane Kenyon's "Not Writing" echoes Neruda's poem for a different reason: it describes a situation in which an individual feels a desire to write, but is unable to do so. But Kenyon's approach to this particular conflict is distinctive. In a spare, short poem of six lines, Kenyon conveys the image of a wasp attempting unsuccessfully to fly into its own nest. Only the poem's title lets us know that the image is a metaphor, in which the wasp represents the writer, and the "papery / nest" the materials of the writing process. The wasp is "unable / to enter its own house," the nest's interior. Thus, here, the inside of the nest seems to represent an embryonic, closed-off work of writing, present but unavailable thanks to a case of writer's block. The poem suggests that a writer's finished work exists within them, waiting to be found rather than constructed from scratch. This poem echoes Neruda in a sense, by portraying a person who wishes to write but finds themself unable to express or even fully discern their thoughts.
Finally, a number of poets throughout history have expressed, in their poetry, a frustration with an impossible poetic demand—that of balancing originality with emotion. This tension has been a particularly rich topic in love poems, perhaps because love poetry, by virtue of its near-universal topic, is at particular risk of steering into cliche. The most famous poem dealing with this particular poetic difficulty is Shakespeare's Sonnet 130, also known as "My mistress’ eyes are nothing like the sun." In that poem, a speaker positively compares a lover to elements of nature often seen in hyperbolic, metaphorical praise. Following in this tradition, the contemporary poet Carol Ann Duffy uses snatches of text from sonnet 130 as well as a variety of other love poems in her work "The Love Poem." This poem describes a writer's frustration as they attempt to write a love poem without resorting to cliche. "let me count the ways - / or shrink to a phrase like an epitaph," Duffy writes, in a vivid description of the difficulty of succinctly summarizing strong feelings.
The speaker of Neruda's "Tonight I Can Write" seems to assume, at least at first, that feeling heartbroken will neatly lead to the poetic expression of heartbreak. But this speaker soon discovers that the link between feeling and writing is more complicated than expected, and, in their own ways, the speakers of these other poems come to the same conclusion. For Bukowski's speaker, writing is an emotional need in itself. For Kenyon's speaker, writing requires accessing one's inner feelings and thoughts—itself a complex, finicky task. And for both Shakespeare and Duffy, the linguistic expression of love is rendered more complicated because of the way literary history looms, making certain passionate descriptions feel deadened by overuse. Thus, with this poem Neruda himself joins a long tradition of poetry that explores literature, its relationship to feeling, and its emotional roots.