οὐδ' ὁτιοῦν

From LSJ

αὐτὸν κέκρουκας τὸν βατῆρα τοῦ λόγου → you have struck the very threshold of the argument, you have struck the most important and chiefmost point

Source

Greek > English (Woodhouse)

not a jot, not a whit, nothing whatever