D&D 5E Why are Persuasion and Intimidation separate skills?

[Greenstone.Walker]

The difference is in the consequences.

For example, I need to get past a guard.

I can persuade them to let me pass in return for a bribe. I can intimidate them to let me pass or I hurt them. I can deceive them to let me pass thinking I am supposed to be there.

In all three cases, I succeeded in my goal (that is, I got past the guard) however the consequences are all very different. In the first case, the guard is pleased with their extra money but guilty about letting me pass. In the second case, the guard is resentful and angry. In the third case, the guard just thinks they've done their job.

 

[amethal]

From another perspective, that "arbitrary" point was their best judgment on the optimal number for the game, and is the result of their testing and expertise in game design. Could you nudge it up a little and add a few more specialized skills? Sure, that's exactly what 3e had with things like Sense Motive and Gather Information.

3e only had one more social skill (Gather Information) and that was removed in Pathfinder.

Having Persuasion, Intimidation, Deception and Insight as separate skills (or Diplomacy, Intimidation, Bluff and Sense Motive if you prefer) seems to be the general consensus as to where the optimal point lies. Intimidation can sometimes be a bit difficult to apply to the D&D game, however - if you've already killed three ogres today the fourth one isn't going to seem that intimidating, whereas a weedy halfling might be able to fireball an entire street ...