Prior civilizations collapsed after over-exploiting their environment, and we're making the same mistake on a global scale. Our complex supply chains based on fossil fuels are rather fragile - we will likely survive a collapse at reduced quality of a life, however total recovery may be slow or impossible depending on remaining resources.
We can produce more food than ever with less energy. Knowledge transfer is always improving, and with computer programs it will be even easier to transfer knowledge.
You guys need to clarify what "a collapse" is. Not eating as much meat? Do you really think that we would not be able to power our computers or not be able to produce rice/wheat on any industrial scale?
The amount of FUD spread without any foundation for it is maddening.
Yes, but civilizations and empires are not representative of the progress of humanity as a whole. Besides, isn't Dark Ages a rejected term by historians now? In addition, what is 200-400 years in the history of civilization? Of course there will be volatility - just like life on an individual level, the stock market, annual crop yields, etc.
An abrupt, significant, and wide-spread regression in quality of life, coupled with cultural and technological stagnation. Something like the Late Bronze age collapse ( https://en.wikipedia.org/wiki/Late_Bronze_Age_collapse )
It is a reasonable low-probability high-risk concern, given (unordered):
* Depleting fossil fuel reserves: most obvious risk; dominant fuel source for transportation and agriculture, dominant energy source for industries, dominant material in many consumer goods.
* Climate change: threatens some regions' agricultural and ocean productivity, pressuring human migration, spreading diseases.
* Exhausted oceans: oceanic deadzones are spreading, loss of fishing as a food source is a serious risk for parts of Asia, which will put additional pressures on agriculture and motivate economic migration.
* Over-use of antibiotics and vaccines: risk of super-bacteria/virus plagues, mostly in agriculture and 3rd world nations.
* Depletion of aquifers: imminent risk amplified by climate change. America's food production is heavily reliant on effectively non-renewable aquifers, depletion or poisoning through fracking are serious risks.
* Globalized economy/supply chains: coupling economies improves efficiency but introduces the risk of cascade failures.
No one of these problems are an existential risk by themselves... but they are all interrelated and poorly understood, which impacts our ability to effectively preempt wide-spread impact.
Humanity will recover should the worst happen, but I think it's better to avoid the set back in the first place.
