The future of humanity seems insecure. Rapid climate change, political division, our greed and failings make it hard to look at our species with a lot of optimism and so many people think our end is in sight. But humans always thought they lived in the end times. Every generation assumes they’re important enough to witness the apocalypse and then life just goes on. This is a problem because it leads to short term thinking and prevents us from creating the best world for ourselves and our descendants. What makes this worse is that we actually may live at an extremely critical moment in human history. To understand why, let us look at the temporal window of humanity and ask: When will the last human be born and how many people will there ever be?