In 1972, Donald M. Murray published a brief manifesto titled "Teach Writing as a Process Not Product," in which he argued that English teachers' conventional training in literary criticism caused them to hold students' work to unhelpful standards of highly polished "finished writing."[2] Teachers, he explained, ought to focus less on correcting students' written products and focus more on involving students in "discovery through language", which Murray believed for "most writers most of the time" involved a process: i.e., stages of "prewriting, writing, and rewriting".[2] Though Murray was not alone in advocating process-based instruction, this manifesto is regarded[3] as a landmark articulation of the differences between process and product orientations in the teaching of writing.