There once was a ship called the Enterprise,
whose leader was never taken by surprise,
for he was surely no Jerk,
but a rather cool Captain Kerk,
tis no wonder the Galaxy was his prize.

A jerk is a rapid and/or erratic movement. A sway is smoothe, even, controlled without being forced. A jerk is also someone who cares not a whit about others except insofar as they can hinder or be of use. To sway someone, you must listen to their opinion, acknowledge it and based on the structure of their world view, show how their beliefs are inconsistent, or how the opinion to which you are trying to sway them, is consistent with their prior views.

Other antonyms suggested: glerk, sillyhead, dako, scientist, friend, angel, clever, nice guy, sweetie, grandparent, mensch, ablerk, gentleman.