American scholar of English literature and persuasive teacher, known for his scholarly method in tracing authors' sources and his allusive style of speaking and writing.

Lowes received his A.B. degree from Washington and Jefferson College (Washington, Pa.) in 1888 and taught mathematics there until 1891, when he received his M.A. degree. After teaching ethics at Hanover College, in Indiana, Lowes in 1902 began graduate studies in English at Harvard (Ph.D., 1905). He taught English at Swarthmore College (Pennsylvania, 1905–09) and at Washington University (St. Louis, Mo., 1909–18) and then joined the Harvard faculty, where he remained until his retirement in 1939.

Lowes's first book was Convention and Revolt in Poetry (1919), an account of innovations and the ensuing reactions to them in the history of English poetry. His masterpiece is The Road to Xanadu (1927), which traced the origins of the inspiration and wordings in Samuel Taylor Coleridge's “The Rime of the Ancient Mariner” and “Kubla Khan” in sources indicated by records of the poet's reading in his notebooks. The book was popular among scholars and poetry readers. Other works by Lowes include Of Reading Books and Other Essays (1930) and The Art of Geoffrey Chaucer (1931).