The emerging generation throughout the world, represented by people like Disha Ravi and Greta Thunberg, have shared concerns that cut across differences between nations and classes. “Workers of the world unite” was a great slogan for the 19th and early 20th centuries. Today it’s a case of young people of the world uniting, supported by older allies. Not for dictatorships of the proletariat, but for new forms of democracy based on mixed economies and renewable energy.

Your "simplest" answer raises a big unanswered question. On other planets with start conditions comparable to Earth’s what sorts of things happen — what sorts of processes, what sorts of emerging systems—if not processes and outcomes comparable to those that have happened here?

The Earth may be some kind of rare, but is it a kind of rare that rules out life and intelligence on other worlds?

You say Earth has "just the right combination of elements". Yes, the combination of elements found on Earth is just fine for the forms of life that have emerged on Earth... How could it not be?

Even in this solar system, there may be one or more other worlds that have just the right combination of elements for something that lives there. After we've had a better look at worlds like Europa, Enceladus, and Titan, not to mention Venus, we'll likely be in a better position to assess how abiogenesis and evolution can or can't work on the planets and moons in other systems.

Very good article! Taking the word "whore" in its literal sense, as a woman who has provided cuddles-for-cash, we have one in an Australian state parliament. Her name is Fiona Patten, she's a Member of the Legislative Council in Victoria, and she's neither secretive nor apologetic about the aspect of her CV I've just mentioned. She's published a book entitled Sex, Drugs and the Electoral Roll: My unlikely journey from sex worker to Member of Parliament. Fiona Patten is a political ally of Victoria's Premier, Dan Andrews, and has recently drafted a major reform of Victoria's prostitution laws. Is she an "epic whore"? I think yes... I mean, whatever you think about her policies, there is surely something epic about her forthrightness.

Anything involving interstellar travel, e.g. interstellar colonisation, interstellar war, is going to involve massive energy costs…

The percolation theory of Geoffrey Landis proposes that interstellar colonisation may be possible, yet so difficult that even highly advanced civilisations sometimes decide not to attempt it. …

Based on what you've written, I'd say that when he accused you of treating him like a whore, he meant that he felt diminished by the prospect of a sudden complete end to everything you'd been sharing... The fact that the two of you remained in contact years later, texting each other videos, cartoons etc, shows that actually there's been a lot more going on between you than the w-word seems to imply... Hope this makes sense?

"So far, about 4,000 planets have been discovered outside the Solar System, none of which have had life on their surface." How much do we actually know about those 4,000 planets? What are the grounds for saying that none of them have life on their surface?