Each person at the core of their psyche has a primal state that never changes. One of the best tools in Jyotisha, the ascendant lord of D60 chart tells us about this. But for a moment, ignore Jyotisha. Let us consider that there is a structure to the Universe, and it is not random. Numerous species at the very core level are about multiplication and division, which can only be possible if they are self-replicating. That means there must be a mathematical interpretation of it, which we may know or don’t know. Now apply this to people, at the core they are fixed it is unchangeable because if it changes then the equation or the mathematical interpretation of the Universal order will fail. Now, we may look at someone and say, what a transformation. When we say that it is our perception that has changed, not the subject of interest, most likely not. So, why did our perception changed? Maybe because we started with assumptions, delusions or convoluted data right from the beginning, that threw us off tangent. Consider the example, when people get drunk and do diabolical things and they blame it on the drinks. But it is not the drinks, it is what is within and will always be. At the core every person always remains the same, they could evolve but never change. I have seen people with conversations about how regretful they are when they dehumanize someone and then they would say, “Oh, if we had known his/her spiritual rank we would have treated him/her better.” It is the same analogy of the drunkard not taking accountability because you don't need some rocket science to treat someone as human. One of the easiest analogy would be, lets say a monkey, it could evolve into higher forms of monkey but it is not going to be a bird. So, at the core what someone is can evolve but it will never change.