Unfortunately, in this game, intelligence does not affect the vocabulary. I remember in Fallout-2, when playing with normal intelligence, you meet one dude who looks like idiot. And if you put intelligence = 1 for your char, then you can have a very meaningful conversation with him
Having stupid conversation options is not a rule in roleplaying game. Especially when it's usually Tim Cain's game that has it (he also said it's mostly pain in the ass to make).
