In the example being discussed we have a body. I can't think of a clearer example of death than one where you can point to the corpse or remains. You couldn't assert that you died 25 minutes ago - since death is the termination of your existence and so logically precludes asserting anything (nothing could count as evidence for you doing anything after death, although your corpse might do things) - but if somebody else asserted that you died 25 minutes ago then they could presumably point to your remains, or explain what happened to them. If you continued to post on the Internet, that would be evidence that you hadn't died. Although the explanation that someone just like you was continuing to post on the Internet would be consistent with your having died.