Great conversation. But my god I hate all that "but we don't see any aliens" crap from anyone, especially from scientists. I mean, how do we see aliens even if they are nearby, cosmically speaking? Do you know the distance to the nearest star? There is no way we can detect any electromagnetic waves from any civilization that far away. Maybe if they emit them specifically in our direction with their most powerful parabolic emitter, designed for just this purpose. What are they talking about? LOL. We wouldn't see aliens if they lived near Proxima Centauri, let alone the rest of the Universe, which is, may I remind you, is mindfuckingly vast. They can be living on every planet outside Solar System, and we would have no idea. Speculating about rarity of aliens at this point is just stupid.