William Hughes Mearns (1875–1965), better known as Hughes Mearns, was an American educator and poet. A graduate of Harvard University and the University of Pennsylvania, Mearns is remembered as the author of the poem "Antigonish" (or "The Little Man Who Wasn't There"). However, his ideas about encouraging the natural creativity of children, particularly those age 3 through 8, were novel at the time. It has been written about him that, "He typed notes of their conversations; he learned how to make them forget there was an adult around; never asked them questions and never showed surprise no matter what they did or said."

Mearns was a professor at the Philadelphia School of Pedagogy from 1905 to 1920. Starting in 1920, he served as head of the Lincoln School Teachers College at Columbia University. He was a proponent of John Dewey's work in progressive education.

Mearns wrote two influential books: Creative Youth 1925 and Creative Power 1929. Essayist Gabriel Gudding credits those books with "[lighting] a fuse" under the teaching of creative writing, influencing a generation of scholars.

Mearns is credited with the well-known rhyme, composed in 1899 as a song for a play he had written called The Psyco-ed. The play was performed in 1910, and the poem was first published as "Antigonish" in 1922.

Mearns also wrote many parodies of this poem, entitled Later Antigonishes, such as "Alibi":

Mearns was born on September 28, 1875 in Philadelphia, the son of James H Mearns and Lelia Cora (née Evans).

On December 22, 1904 he married Mabel Gledhill Fagley at St Mark's Church, Philadelphia. They had a daughter.

Mearns died on March 13, 1965 in Bearsville, New York.