He didn't presume it was the other Jedi who seemed certain of it.

Sometime back I was helping SSWR with a concept for a scene in the Temple, Qui-Gon has to speak to the Council so Anakin joins the novices for a tour of the building given by an ancient human Jedi Master.

He explains that the Sith once ruled the Galaxy from the Temple which was then their battle fortress and the first Jedi were rebels who infiltrated the fortress and learned about the Force from the Sith but tried to use only the Lightside to defeat them by spreading rumours to make them fight and kill each other.

There was a prophecy that a chosen one would come to bring balance to the Force and destroy the Sith but the Sith were destroyed and the chosen one was never found.

Anakin has the same sense of cold deja vu about the temple that Luke later has for the cave and the Master explains that the building is still strong in the Darkside (because terrible things were done there and the building is still hungry for blood and pain) the Jedi use this to remind them where darkness can take them but Anakin is not happy with the explanation.

A scene like that would have given the PT a whole new backstory of it's own, but it would mean replacing Jake Lloyd in practically every scene he is in.