Believing New Thoughts!

I am embarking on the Believing New Thoughts program and I have a question. Does the new thought have to be about something concrete that I can see/touch; e.g. “I will make $100000”, or “I will live on the water”? Or can it be something related to self-development, e.g. “I am as worthy and lovable as everyone else in the universe”? Obviously I would like to do the latter, or I wouldn’t be asking!