It seems quite true that writers are destined to compose their works under the spirit of the day. Each age bears its own zeitgeist according to which the world views of the writers are formulated. In order to manifest the zeitgeist of their age, poets have accordingly invented and put into practice new poetics most relevant to the overall spirit of their age. This essay examines the two different poetic experiments performed by T. S. Eliot and Robert Lowell. Shattering the poetic experiment of the British Romantic period, and employing that of metaphysical poetry, T. S. Eliot ventured to establish his own poetics: “poetry is an escape from emotion.” He thought that the poetics established before his age was not appropriate to express his own age. His poetics was an attempt to communicate with his age and to express its spirit as well. It was quite successful due to his contemporary European aesthetic atmosphere―Modernism; it also influenced poets on both sides of the Atlantic Ocean for several decades. In the mid-1950s, however, his poetics was challenged by a new poetic experiment in America. It was Robert Lowell that challenged Eliot’s poetics and established a new poetic experiment: “confessional poetry.” Lowell also thought that the overall climate of America at his time should be embodied by a new poetics: manifestation of the poet’s own self. This new poetics helped deal with his autobiographical facts: that very forbidden fruit for Eliot. Like that of Eliot, his poetics was considered successful, breeding a number of sympathizers in the contemporary and succeeding periods. Whatever frictions exist, however, their poetics have some things in common with each other. Just as post-modernist philosophers suggested, neither was able to be extricate himself from the networks of tradition and the historicity of language.