Metaphysical poets Flecknoe" and Joseph Addison, in quoting him, singled out the poetry of George Herbert as providing a flagrant example. There is no scholarly consensus regarding which English poets or poems fit within the Metaphysical genre. In his initial use of the term, Johnson quoted just three poets: Abraham Cowley, John Donne, and John Cleveland. Colin Burrow, writing for the "Oxford Dictionary of National Biography", singles out John Donne, George Herbert, Henry Vaughan, Andrew Marvell, and Richard Crashaw as 'central figures', while naming many more, all or part of whose work has been identified as sharing its characteristics. Herbert Grierson’s "Metaphysical
Metaphysical poets Lyrics and Poems of the Seventeenth Century" (1921) was important in defining the Metaphysical canon. Helen Gardner's "Metaphysical Poets" (1957) also included 'proto-metaphysical' poets such as William Shakespeare and Sir Walter Raleigh and, extending into the Restoration, brought in Edmund Waller and Rochester. While comprehensive, her selection, as Burrow remarks, so dilutes the style as to make it "virtually coextensive with seventeenth-century poetry". Late additions to the Metaphysical canon have included sacred poets of both England and America who had been virtually unknown for centuries. John Norris was better known as a Platonist philosopher. Thomas Traherne's poetry remained unpublished until