I have opinions about this page.
In general, I think it’s very important to give information to the players. Even if you have to say “you don’t know”, you should then continue with saying why this is outside of your reach, or where you can reach someone or something who do know. Sometimes I also find it useful to say something dismissive as an answer (while being very emotive about it), to push them away from a line of inquiry that’ll only derail the game. The players trust me enough to know this is not an antagonistic attempt at misdirection; I’m only mentioning this because I know there are tables where this isn’t taken for granted (which is unfortunate).
So in short, the information must flow, but it should also be controlled, for the betterment of the game. I have said lots about this, but what we see here is an example (a mild one, mind you) of the way I provide information regarding the “Is she lying” question.
Because most GMs are not trained actors, and most players are not trained social butterflies, there’s lack of skill on both sides when trying to simulate a situation in which a PC tries to “read through” an NPC and get information through their body language, phrasing, what they chose to omit, their mood, and the like. There’s an incredible amount of information beyond what’s literally being said, but for us, sitting around the table, there’s little we can do beyond what is literally being said, or at least, not necessarily very well.
The solution for this, like with swinging a sword and many other things in the game, is to delegate this to abstract rules and possibly randomness. (There’s still a lot more to be said about the importance of introducing rules in “pure RP” situations, but that’s too big a topic for right now). The trouble with rules is that we tend to look at them as giving decisive answer – I made it, or I didn’t; I hit them, and if so then for how much, etc. Even if there are several levels of success, we still have expectations that the rules will give us some sort of an answer.
This is not how conversations work, however. Talking is messy and complicated, and only rarely one can get a straightforward answer. So how do we solve this issue? On the one hand, we expect to get a clear answer, and on the other, we shouldn’t get one.
I recommend (as always) to take a step back from The Truth, into perceptions. In other words – the GM tells the player what their character perceives, and lets them decide what to think about it. If you made the Intuition vs Deception check, or in our case Notice vs Persuasion, then you’ll be told what your character understands from the situation, completely avoiding “what’s the truth of the situation”.
If she rolled well, you don’t know she’s lying, but you might get the sense she’s hiding something. If you get a raise, you might realise what sort of thing she avoided talking about. Or perhaps you manage to catch her in a blatant lie, or a confused/ashamed gaze, and can then grab the opportunity and Intimidate her with +2 to reveal what she’s been lying about.
In any case, you can’t just know what she knows. It goes the other way around; when you Persuade someone, you don’t mind control them, you improve their attitude toward you so they’re more open to suggestions. People should be complicated – not all the time (some NPCs truly are just background characters, not conversation partners) but certainly as a general rule. Even though the rules sometimes push us there, in most cases, absolutes should be avoided in conversations.