You can’t actually know you’ve been conscious for longer than this moment
Something I’ve thought about for years and never managed to talk myself out of.
Everything that tells you you’ve lived a whole life is sitting in your brain at this moment. Your memories, your childhood, what you did yesterday. If you’d only been conscious for the last second you’d still have all of that and it would feel exactly like it does now. There’s no way to tell the difference from the inside.
So I don’t believe in a continuous self. Your brain tells you there is one and you’ve got no way of checking.
I also don’t think time flows. The block universe idea in physics says past, present and future all exist together, like a film reel where every frame is already there. Relativity makes it more complicated than that but that’s the gist. Your life is a line through it and every point on the line thinks it’s now.
What I actually believe is that the universe itself is conscious at the fundamental level, in ways we can’t understand. Our brains are just equipped to give us the illusion that we’re conscious as individuals, with our own experiences. There’s really only the one thing and we’re all it, each convinced we’re separate because we only have our own memories.