Interesting debate, both parties operated on the basis of certain assumptions about physical and non-physical reality. I have a problem with this because I feel that first the assumptions should be declared.
For instance, the teacher said that if there is a permanent self, then nothing can change but that is based on an assumption which he did not declare. The assumption is that if there is something permanent that something cannot be adjusted ever and also that something cannot be fused with other things which constantly change.
I feel that what we have is multiple selves, with variation in their perceptions and approaches to figuring what is reality. That is wonderful indeed!