From Terry Pratchett´s Unseen Academicals (very minor/not significant spoilers):
‘You had to find the truth for yourself. That is how we all find the truth.’
‘And if the truth is terrible?’
‘I think you know the answer to that one, Nutt’ said the voice of Ladyship.
‘The answer is that, terrible or not, it is still the truth,’ said Nutt.
‘And then?’ said her voice, like a teacher encouraging a promising pupil.
‘And then the truth can be changed’ said Nutt.
If you feel the need to put the quote in rot13 to avoid spoilers, it's probably not worth posting at all (I don't think that this quote spoils anything significant about the plot in any case.)
Here's the new thread for posting quotes, with the usual rules: