If you think you can or you think you can’t, you’re probably right.
(Henry Ford probably said something like this, but he probably heard something like it from someone else; see here)
A reflection for today: if your viva is coming up, honestly, truthfully, do you think you can pass it? If you do, what are you going to do to make it a certainty? If you think you can’t, what are you going to do to get help? Either way, what are you going to do?