For every one of those causal steps, you will find a person surprised that they are at that particular causal step. So this surprise is not information about the world—it’s a diagnostic sort of surprise that comes from a contradiction in your definitions. As pragmatist says, said contradiction is probably between the ’I’s in “I am here now” and “I exist in spacetime.” And, personally, I think you should go with “I am here now.”
For every one of those causal steps, you will find a person surprised that they are at that particular causal step. So this surprise is not information about the world—it’s a diagnostic sort of surprise that comes from a contradiction in your definitions. As pragmatist says, said contradiction is probably between the ’I’s in “I am here now” and “I exist in spacetime.” And, personally, I think you should go with “I am here now.”