What would you trust more, in seeking to learn about a person: their biography, memoir or their autobiography?
I would say that if you really want to get to know a person through a piece of text, I would pick a memoir. A memoir would show you how this person thinks. You wouldn’t really have that opportunity if you were just having a conversation with them. Even if you’ve known them for your whole life, they might be living in a completely different world in their head.
Through a memoir, you would also get to see the moment that they intentionally picked and that they intended people to learn more about. If you were there, you would see how they saw that moment through their eyes, maybe even learn what it meant to them.
Memoirs might be the easiest way to learn about a person. I’d say that you can learn so much about a person through the way they think and finding out about the things and experiences that shaped them into the person you may know.