David,There are "thought" beliefs, intellectual models and such, and there are the things you actually build on which may be very different. You can think all the thoughts you wish to think within the "bubble" of a core set of beliefs and the beliefs won't necessarily shift or resolve.
But getting in touch with belief structures--not just intellectual ones, but the core belief sets that define how you see and feel or do not--and modifying them is demonstrably possible. Conversely, getting in touch with your experiences under the concept that experience is the sole reasonable basis for belief, and changing your experiences doesn't seem to work because the conviction is that what you experienced is part of the unchangeable past. And it very much appears that way from within the basic religous convictions of matter, space and time as we usually experience them.
This is probably too long a subject to get into on a thread, though.
A