知り: the -masu stem of 知る
も: a particle
せ: 未然形 (the imperfective form/the -nai stem) of a classical verb す, which is corresponding to する in modern Japanese
ず: 連用形 (the adverbial form/the -masu stem) of a classical negative auxiliary verb ず, which is corresponding to ない in modern Japanese
Thus, it means 知りもしないで/知りさえしないで/知ることもなく even without knowing ~.