Certain minor peculiarities of language are used unconsciously by poets  If such peculiarities appear in the works of more than one poet, they are likely to reflect the language in common use during the poets' time  However, if they appear in the work of only one poet, they are likely to be personal idiosyncrasies
As such, they can provide a kind of fingerprint that allows scholars, by comparing a poem of previously unknown authorship to the work of a particular known poet, to identify the poem as the work of that poet
The labor of analyzing peculiarities of language both in the work of a known poet and in a poem of unknown authorship would not be undertaken unless other evidence already suggested that the poem of unknown authorship was written by the known poet.