NOT talking about nonabsolute vs absolute convergence. I'm talking about conditional convergence. In my analysis text, this was a bit that was covered as enrichment and it straight up blew my mind. I don't get it. How can you simply rearrange terms and come up with a separate sum? They showed a few examples in the book, but it still blew my mind. I don't really have a question. I just find this idea awesome. Also Reimann Series Theorem blew my mind. Does anyone know much about it? The book I had, although clear, wasn't as deep as I would have liked.