There are several different types of votes:
I find the terminology confusing here, it doesn't make it clear that each page can have at most one way of voting.
"Some pages can be voted on, either with a probability vote or an approval vote".
… though the explanation would be even clearer, if it was something like:
"Some pages are claims, on which you can vote. There are two kinds of claims;
- Factual claims, about whether something is true or not. On those, you vote by giving a probability.
- Value claims are about "shoulds". On those, you vote by giving how much you agree or disagree."
… but then, I don't really like that formulation either (I'm thinking aloud here, and haven't properly digested all the concepts).