[visarga]

I don't think personality can change. What can change is the situation and the people you interact with, and depending on them, discover aspects of your personality you weren't aware of before. Maybe that counts as a change, but it's just better self knowledge and world knowledge.

I also think personality is not unique - we have a whole range of "personalities" we employ depending on who we talk with and what the situation is. Thus, personality is a function of self-values and external situation - we have many masks, one for each occasion.