Sort of a complicated question, I'll try to ask. How was I born me and not another?

[EruptedCarcassBloat]

Oh my god, did you really just tell me that my mind couldn't have been inside of a cat? UGH!! I know that. I'm just saying... holy crap how do I even rephrase this differently anymore? Is there any scenario where a person could have not become a person? Like, all the particles that make up our body from birth, they were present there from the big bang, they probably composed some sort of molecules floating around space before the earth was created. The particles in my body probably existed in some form or another from way before I was even born. All of these molecules go into creating one thing or another, and yes a lot of species on earth are related and I could have become a cat, or a monkey, or whatever. But those molecules could also just be sitting there inside of a rock, I could have never come to be. I was just thinking, why am I sitting here right now and not just some primordial substance sitting around somewhere else, not formed into a human being?

...Because "you" are defined by what you are now.

And "Is there any scenario where a person could have not become a person?" makes...no sense.  If a person wasn't a person, it wouldn't have been a person in the first place, so no.  

I mean, some of your old skin cells that you used to have are probably in a tree or rock or bug somewhere, but those skin cells aren't "you."

No, I mean before they became a person, when they were just particles somewhere. Even if for generations, human beings existed from genetics and being a human being is totally congenital, those particles that come together to make a human being, which make up the body of the mother who gave birth to the human being, came from somewhere. They obviously came from food, because food is what is digested and transformed into the molecules that compose the body, and food comes from nutrients in the ground, sentiments, water, whatever. You are nothing more than a conglomeration of matter that has molded itself into you. I know that a person is constantly regenerating cells, which is what makes it all the more strange that I am somehow my brain, and my body keeps shedding these cells and replacing cells, yet i still have a continuous experience from birth that seems like it's been the same me from the time I was born. This illusion of consciousness and being inside of my own head. I wonder how consciousness itself forms, and how you could biologically define the processes that form consciousness. I believe there's a book called consciousness explained which I have sitting on my shelf, which I should get around to reading some time. I've never had anyone explain consciousness to me though in a way that isn't just a really pseudo sciency non answer sort of thing. It's like, I ask what causes consciousness, and people get it in their head that they have the answer and say like "oh it's because you're aware of yourself, don't you know what consciousness is?" I get really tired of the really crappy answers that don't explain things in a deeply informative and mind expanding way.