I completely agree. Over time, an idea can change from one thing to another, to another, to another...and all because of the other ideas thrown into the pot along with it. Add some oregano, the smell changes. Add some salt, the taste changes. And, every now and then, people will do crazy things like add hot sauce and ice cream to the concoction. The foundation of your beliefs changes, but what is in the pot is still you. This reminds me of one of my favorite quote from Fahrenheit 451:
And someday, after it sets in us a long time, it'll come out our hands and our mouths. And a lot of it will be wrong, but just enough of it will be right. We'll just start walking today and see the world and the way the world walks around and talks, the way it really looks. I want to see everything now. And while none of it will be me when it goes in, after a while it'll all gather together inside and it'll be me. Look at the world out there, my God, my God, look at it out there, outside me, out there beyond my face and the only way to really touch it is to put it where it's finally me, where it's in the blood, where it pumps around a thousand times ten thousand a day. I get hold of it so it'll never run off. I'll hold onto the world tight someday. I've got one finger on it now; that's a beginning.