In 1994 he was convinced that the kinds of "compromises" that James Gosling were putting into Java guaranteed it would be dead on arrival. He wasn't wrong, those choices would ultimately limit the language (and they have) but he completely missed the 20 years between then and now where Java would have a huge impact.
When this editorial came out I had moved on from Sun and was dealing the leading edge of what would be the dot.com implosion shockwave and now Bill was telling us it was all pointless, the world would probably die on its own desire to create cool new things. Well he wasn't saying it was pointless per se, he was saying we needed to confront the ethics of what we were doing now instead of in the middle of the crisis. And there is much to like about that, but recall that Facebook was created in a dorm room, not a laboratory like Bell Labs or Sun Labs. So there was no oversight, no 'adult supervision' of people who would ask, as Bill would have, what happens when ...?
So to understand Bill's essay in context I have to ask, "What would he have said to Mark Zuckerberg?" I don't doubt for a moment that had Mark confided in him his vision and his plans, that Bill would have foreseen the size and extent of its impact. Bill is a guy who made more money on Microsoft Stock than on Sun Stock because he sold the latter and bought the former, recognizing that at the end of the day Microsoft would have a larger impact. So what does he do? Does he convince Mark to throw it away? Does he say "You will be one of the richest people in the world but you'll have created a tool that nation states will use to undermine democracies around the world?" And how does Mark respond to that? Probably, "If not me, someone else will figure this out. Look at myspace.com, I'll take the money and figure out the rest after it becomes a problem."
The future doesn't need us, and neither does the present. It is the ultimate hubris of humans from the beginning of time that they are somehow "more special" than the rest of the machine that is the universe. When you read books like "The Vital Question" you might be struck that humans are just a 'step in the path' rather than the starting or ending point of that path. You can imagine self aware machines arguing over the notion that they evolved from meat.
The power of Bill Joy for me has always been his willingness to say something outrageous that was the logical extension of a path through the point of absurdity. And in that moment stretching the pre-conceptions of the people hearing him such that they were able to think of something new that previously they would not allow themselves to think it. I've felt it first hand and seen it in happen in others. The after the meeting discussion that goes "That was the craziest thing I think I've ever heard, but something that might not be crazy is if we did this ..."
Of course, both these guys are experts at the top of their fields, at respected institutes. I possess neither of those qualities.
Life appears common, but multicellular life appears to be extremely uncommon and appears to have evolved only once on earth, at least according to Nick Lane's excellent (though inadvertently depressing) book The Vital Question: Energy, Evolution, and the Origins of Complex Life (https://www.amazon.com/Vital-Question-Evolution-Origins-Comp...). I can't gauge the accuracy of his claims but the book does not appear to have been rebutted, at least from what I've found. Given all the discussion about biology on this thread I'm surprised no one else has mentioned it.
I've been reading "The Vital Question" of late and it has been the first book in a while where I've had several "oh that makes so much sense!" moments. And one of the tenets is that Darwin was correct in the small, and wrong in the large understandings of evolution.
Something that jumped out to me while reading it, is that information extraction drives our technology systems like energy drives biological systems. Read the book and then sit back and analyze Twitter as a multi-cellular organism with information as energy and individuals as cells. A sort of Datasaurus. Fun stuff.
 "The Vital Question: Energy, Evolution, and the Origins of Complex Life" -- http://www.amazon.com/Vital-Question-Evolution-Origins-Compl... based on the recommendation tweeted by Gates and comments here, I read it through cover to cover while camping, and now going through a second reading to pick up what I overlooked the first time.
So in the Drake Equation, I think that F[L] is probably pretty low.
And because eukaroyte genesis is difficult and only happened once (and it took a billion years of bacteria & archea hanging out before we got a eukaryote), and eukaryotes are a prereq for multi-cellular organisms and thus intelligent life, F[i] is also really low.
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