The term 'metaphysical poets' is used to group a number of 17th century poets, the most influential of whom are generally considered to be John Donne, Andrew Marvell, George Herbert and Henry Vaughan. Although in no sense a school or formal movement, they share common characteristics of wit, inventiveness, and a love of elaborate stylistic manoeuvres. Reacting against the deliberately smooth and sweet tones of much 16th century verse, the metaphysical poets adopted a style that is energetic, uneven and rigorous.