Originally Posted by
kyoryu
Either.
The "int character" would do the calculations and be able to tell you the chances of success.
The "wis character" would, by experience, realize that single rolls tend to have more extreme results, and lots of rolls tend to "even out" over time. They might not know that there is an issue, but they'd have the experience to recognize that and look further.
The ideal situation is that the wis character prompts the int character to do the math, leveraging both of their strengths.
Wisdom, probably. The key insight here is that players might not want to bypass all encounters, and that in a game where xp and loot are the marks of progression, that if something is to be seen as a better alternative to combat, it has to provide at least the same level of rewards (compared to the "cost" of combat) in order to be an actually better result.
This could be done through game-theory-like analysis (actual mathematical game theory) but understanding human incentive and behavior seems like a more likely first signal that there's an issue.
So the two are actually similar - the "wis character" would be likely to recognize the potential problem, the "int character" can analyze the problem and determine the severity of it.