This. Nobody is 100% trustworthy in every circumstance. When I say I trust someone, what I mean is that I have a good handle on what sorts of things that person can be trusted about, and what sorts of things they can't.

On second thought, I'm not even sure what "transitive" means here. It seems like it should mean that if you trust your friend's movie recommendations then you trust your friend's friends' movie recommendations? Or maybe something like:

   trustsMovieRecs(A, B) and trustsMovieRecs(B, C) => trustsMovieRecs(A, C).

Their movie recommendations are likely some function that takes their friends' movie recommendations as input (along with watching them), but that's more like an indirect dependency than a transitive closure.