As pointed out by others in this thread, this is basically the doomsday argument all over again. It's a deep subject, and I can't pretend I know much about it,

As pointed out by others in this thread, this is basically the doomsday argument all over again. It's a deep subject, and I can't pretend I know much about it, but one thing that I'd like to point out is that this kind of reasoning is based of the so-called "self-sampling assumption"[1], and that this concept depends of a choice of reference class. Even if Richard Gott is right, what he means when he's talking about "humans" going extinct is "people that I can identify myself with" going extinct. In other words : he can only make assessments on the existence of people like him. Humans are not perfect. Far from it. If anything, the existence of exceptionally smart people like Einstein or Von Neuman prove us that it's possible to imagine a world where everybody is at least as smart as those two. Arguably, that hypothetical future world may very well be outside of Gott's reference class. Such a world could result from the birth of a new Homo species and the end of Sapiens. It could mean that machines would have replaced us. It could mean lots of things, not all of them being necessarily dreadful. My point being : the doomsday argument is not exactly a prediction about the demise of mankind, but rather one about a dramatic change of it. In a way, it's more apocalyptic in the original sense of the world : not the end of times, but a profound change, a new era or whatever. It's a prediction about the end of our reference class. Or in the Kurzweilian sense, the Singularity. 1. https://en.wikipedia.org/wiki/Self-sampling_assumption https://en.wikipedia.org/wiki/Self-sampling_assumption