And sadly with 4 suns the orbit would be chaotic and no periodic pattern would exist to be found. Which ruins the premise of the story.
Foundation also fails because human society is chaotic so his psychohistory would never work.
Foundation also fails because human society is chaotic so his psychohistory would never work.
This is only true for certain configurations of N-body systems. The solar system is an N-body system with periodic patterns, at least at a human timescale.
The periodic behavior of the Solar System is because 99.86% of its mass is in the Sun. So every other interaction is a small rounding error. And therefore the Solar System is chaotic but with a long Lyapunov time - estimated at about 5 million years.
True, Poincaré had already worked out that gravity was chaotic. But Asimov was a chemist and so was unlikely to be familiar with that work.
We haven't discovered much, really.
My strong impression is that it wasn't until James Gleick published Chaos: Making a New Science in the 1980s that there was a popular treatment available to the lay public. And that book lays out many examples from the early 1960s at people like Edward Lorenz and Yoshisuke Ueda being surprised at extreme sensitivity to initial conditions, and having their discoveries met by doubt and disbelief. Which indicates pre-1960, only a fairly niche audience was strongly aware of chaos theory among either the lay public or scientists.
Hinged pendulums which exhibit chaotic behaviour have been a popular demonstration for about 100 years.
Just because the first pop-sci glossy coffee table book to mention chaos wasn't published until the 1980s, it doesn't mean that anyone who studied maths or physics - particularly at a level that would allow them to teach at a university - would not have even heard of chaos theory.
The double pendulum actually goes back further. It was studied in the 1700s. But what could be done with them was limited until computer simulations were available - in the 1960s. The same time that chaos as a subject became a thing.
And your claim that chaos was something that anyone with a high-school grasp of mathematics would have known about in the 1940s is supported on nothing more than your say-so. And directly contradicts multiple reports of working scientists in the 1960s. For example from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3202497/ you find:
Lorenz considered, as did many mathematicians of his time, that a small variation at the start of a calculation would Induce a small difference In the result, of the order of magnitude of the initial variation. This was obviously not the case, and all scientists are now familiar with this fact.
In other words people with PhD in directly relevant fields in the 1960s actually were ignorant of basic facts about chaos theory that are now known to every high school student. Even the phrase we all have heard to capture it, namely "the butterfly effect", dates from the 1970s.
And with that, I'm done. You're providing assertions that run counter to my citations, and are refusing to accept information that I cited about what was and was not general knowledge. There is no point in continuing.
The premise is true but the conclusion does not follow. Asimov was one of the most prolific authors of popular science books including astronomy, cosmology, physics, etc. It's entirely plausible that he was familiar with chaos.
It was unlikely that he was unfamiliar with chaos. Doubly so given that the first prediction of what we now call chaos theory is that we won't see the periodic behavior that is a fundamental premise of the story.
But the actual story as told? The regularity of civilization collapse was rather central to the people in the story.
Ant's are also chaotic as individuals, but if you get enough of them you can model them easily. We can already semi-predict global human behaviour; population graphs, economic charts, actions of specific demographics. When enough humans walk down a street, you can model their flow with fluid dynamics.
Psychohistory wasn't a study of the intricacies of the human condition, it was an iterative model that follows general trends. It just happened to be sophisticated enough to predict thousands of years into the future and to allow for outliers.
However when you look back over the last 200 years, one of the striking features is that every 10 years or so people are concerned about something very different than they were before, and which was often a result of a crisis that few were ready for. For example nobody in the Clinton era would have predicted 9/11. The 2008 financial crisis caught most of us by surprise. COVID was on nobody's radar. Nor did we expect Russia to launch a full-scale invasion of Ukraine (nor to lose if they did). And so on.
I can't tell you what we'll all be worried about in 2030. It won't be COVID or Ukraine. My guesses include financial collapse, climate change, the collapse of Russia, the invasion of Taiwan, and so on. But odds are that it will be none of those things.
COVID was on nobody's radar
one of the striking features is that every 10 years or so
Trying to fit it into a shallow truism like "every 10 years, it's something!" is some kind of magical lazy thinking, right up with "it takes 10,000 hours to master a thing!" and "celebrities always die in threes!"
The Mule shows Asimov knew psychohistory would never work on its own.
The recorded prediction of the crisis with the independent traders didn't happen, because of The Mule. This was the Era of Deviations, and it took centuries for the Second Foundation to manipulate things back to the Sheldon Plan.
And of course, the influence of R. Daneel Olivaw across nearly 20,000 years, guided by the Zeroth Law of Robotics.
[minor spoilers below] It is practically a racist book where everybody non-chinese is evil, conspires to harm chinese in a comical villain fashion, should be killed, and is killed eventually. I get that 100 years ago similar literature was OK in the west too, but we moved our societies quite a bit since then.
100 years ago? Today, the ratio of militaristic "America F** Yeah!" sci-fi vs every other language is probably 100/1 and the amount of times the Chinese and Russian are the ones portrayed as evil in that literature is literally orders of magnitude greater. Are those also racist books?
I've not noticed that. OTOH as a brit, the number of times I see us portrayed in American films as cold, unemotion, untrustworthy, manipulative, I could go on...
Edit: on reflection that does seem to have died down a bit in recent years.
It was kind of refreshing to have someone else be the villain for once.
There appear to be stable configurations for the 4 body problem too, even if the 4 masses are similar.
Its not fair to say there's no periodic pattern possible with 4 suns, then, even though most initial configurations might lead to chaotic behavior.
Also, there are six suns.