So, for some time now I've been mulling over an idea for social encounters and social interaction with NPCs.
Usually, these encounters are solved using one, or more, social skill checks, and la-di-da ... moving on to action.
Social combat is also something that has been elaborated on in various places, more or less successfully, more or less enjoyable.
I have been thinking more on the nature of NPCs and their strengths and weaknesses, regardless of characteristic or skill ranks.
I've been considering to make some NPCs will be more open to emotional arguments, others to rational and logical arguments, and some to arguments based on values and character (either their character or the PCs character). So, pathos, logos, and ethos. Of course there's also kairos, telos, and topos. But let's not get carried away...
For most NPCs this system is basically just adding a cumbersome quality to the gaming, which isn't the desired goal. Yet, for some NPCs, I think this could add a nice touch to role-playing and challenge the players in new and different ways, that - I believe - can generate more interesting and enjoyable experiences.
So, I'm devising a "system" where NPCs may have a status on one or more of the three types of arguments. This status is either +, 0, or -. Most NPCs will by default have 0 in all three, which means it doesn't come into play. We know where our players have a strength or weakness, what player is more susceptible to rational arguments, and we know our players' strategies and tendencies when it comes to the types of arguments they use. This may then be rewarded with some NPCs, and make other NPCs more challenging.
The idea, is that a NPC with +logos, will be more susceptible to this type. Providing players a bonus on a check, and/or more information on a successful check. Players may be explicit on what they are trying to convey and how, or they may roleplay it (where you the GM interpret and define what strategy they are using). If the same NPC has -pathos, and the players are making emotional arguments, they get a penalty, or less/poorer information on a successful check.
This may also add roleplaying cues and inspiration to the GM in the moment, as the susceptibility may also imply what strategies they will use.