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Antifragility in complex dynamical systems

nature.com

101–110 of 115 posts

Re: Antifragility in complex dynamical systems

#101
post #11
post #6

Earlier quoted context omitted.

but death isn't a system or organism...

> but death isn't a system death is entropy. do you know of a system without entropy? > or organism... boy are you going to be surprised when you answer that knock on the door, eh?

I didn't say that complex systems can't die, I said death itself is not a complex system. Antifragility is specifically a property or behavior of a complex system. "Death" can't anymore be antifragile than the color red can be.

Re: Antifragility in complex dynamical systems

#102
post #18
post #14

Earlier quoted context omitted.

The leading three authors are from Germany, Mexico, and Switzerland resptfully. The sentence they want should capture the notion of being robust when poked with a stick. A pencil on it's tip is a fragile system, one burp and it falls to the table, far from the intial state. Marbles in fruit bowls are anti-fragile, given a good shake (up to a threshold) and they remain in the bowl and return to the low centre. Reading…

> A pencil on it's tip is a fragile system, one burp and it falls to the table, far from the intial state. Marbles in fruit bowls are anti-fragile, given a good shake (up to a threshold) and they remain in the bowl and return to the low centre. I believe what you're describing is a stable vs unstable system, not fragile vs antifragile. You can perturb a bowl with a marble, and the marble will still end up in the midd…

Thanks for this- lots of people on here are misunderstanding the concept of anti-fragility as the same as robustness, e.g. in a control system. They are not at all the same- anti-fragility is a system progressively improving in a lasting way in response to an appropriate stressor, e.g. like a weight lifter getting stronger from weight training, or getting weaker from skipping training. It is not robustiness but literally a negative fragility: a system whose function is impaired by lack of stress (e.g. fragile to lack of stress), and improved by stressors.

Re: Antifragility in complex dynamical systems

#103
post #29
post #25

Earlier quoted context omitted.

My initial motivation was to point out the authors likely weren't native in English. I meandered onwards to waffle about the nature of what they were describing, which to my mind at least begins with a notion of stability, in pursuit of a better succint opening line (which I don't have). You've said: Fragility and antifragility aren't about stability (returning to equilibria), but gains or losses after perturbation,…

Thanks for engaging. You're right in that the ideas are not new, but I feel the language and the framing somewhat is. I'm not sure if you've come across N. N. Taleb's work -- he's the guy who coined the term "antifragility" = things things that benefit from perturbation. In it he argues that the antifragility is a property of systems that satisfy Jensen's inequality [1]. If the system's function f is convex, then: E[…

> You're right in that the ideas are not new

It's not just an old scientific idea, but a popular idea discussed at length by the ancient greeks: Talebs whole thing is taking ideas from ancient philosophy, especially stoicism and translating them into rigorous math concepts for modern applications and audience. He's also obsessed with "The Lindy Effect" which implies that older ideas are generally also likely to be more valuable and lastingly useful.

Re: Antifragility in complex dynamical systems

#104
post #67

Earlier quoted context omitted.

Arguably it does, the heat death of the universe option would spell the end of entropy, and the end of death (unless you believe in a conformal cyclic universe)

Actually yeah fair enough; I’ll grant that death may be a system.

A complex dynamic system has a large number of working parts, and responds in specific ways to inputs and stressors. It just doesn't make sense to think of death itself as a "complex system." They are certainly related- I think death could be seen as an event that irreversibly dismantles a complex system in some way, such that the parts no longer function together as a system.

Re: Antifragility in complex dynamical systems

#105
post #14
post #8

Earlier quoted context omitted.

Well it is in a journal called "complexity." But I agree, that sentence is awful, I'm surprised they decided to lead with it, and nobody proof reading the paper objected.

The leading three authors are from Germany, Mexico, and Switzerland resptfully. The sentence they want should capture the notion of being robust when poked with a stick. A pencil on it's tip is a fragile system, one burp and it falls to the table, far from the intial state. Marbles in fruit bowls are anti-fragile, given a good shake (up to a threshold) and they remain in the bowl and return to the low centre. Reading…

The sentence captures the notion clearly, it just sounds a little awkward, especially for an opening sentence in an abstract, which is usually carefully crafted. I think you're probably correct that this is because the authors aren't native English speakers.

Re: Antifragility in complex dynamical systems

#106
post #50

Earlier quoted context omitted.

Resilience is not the same, a system is anti-fragile if it gets stronger under stress. Resilience is just "not getting weaker".

Pedantically-not pedantic, but isn’t resilience the ability to quickly recover?

Ok I looked it up. It is to withstand or recover quickly, or the ability to spring back into shape; elasticity. (Oxford American)

Re: Antifragility in complex dynamical systems

#107
post #97

Earlier quoted context omitted.

I mean you can go and argue with the biologists and economists if you need to. I'm just delivering the meesage.

My argument here would be that this isn't that new, all told? And... I would be shocked to find a lot of disagreement there. Indeed, other threads are already pointing out that terms already existed that covered this general idea. My problem with antifragile, as often offered, is that it is positioned as something that gets stronger from being damaged, full stop. But... there is literally nothing on earth that would…

I guess it's important that the negative signal be relatively small compared to the affected system, like antivenom doses, but also it needs to be predictable/differentiable to some degree. If two different doses of venom never had the same molecular patterns then it would be impossible to immunize against it.

A one-time supernova event would destroy a solar system, but the universe itself is antifragile to supernovas, and actually has built emergent spatiotemporal structures which depend on supernovas as part of their lifecycle. New solar systems rise up from old supernovas.

Predictability/differentiability of internal and external states is key for building robust systems, negative signals alone are often just detrimental. You can't learn from chaos.

Re: Antifragility in complex dynamical systems

#108
post #104

Earlier quoted context omitted.

Actually yeah fair enough; I’ll grant that death may be a system.

A complex dynamic system has a large number of working parts, and responds in specific ways to inputs and stressors. It just doesn't make sense to think of death itself as a "complex system." They are certainly related- I think death could be seen as an event that irreversibly dismantles a complex system in some way, such that the parts no longer function together as a system.

I was thinking of systems more as just processes that have low-entropy behavior, i.e. those that are predictable in some meaningful way. If one takes the process of death, which is really a behavior of any low-entropy system, to be its own object, I do think that object would be a system under my definition. I agree that yours does not come to the same conclusion, and perhaps my definition of system is too broad.

Re: Antifragility in complex dynamical systems

#109
post #97

Earlier quoted context omitted.

My argument here would be that this isn't that new, all told? And... I would be shocked to find a lot of disagreement there. Indeed, other threads are already pointing out that terms already existed that covered this general idea. My problem with antifragile, as often offered, is that it is positioned as something that gets stronger from being damaged, full stop. But... there is literally nothing on earth that would…

I guess it's important that the negative signal be relatively small compared to the affected system, like antivenom doses, but also it needs to be predictable/differentiable to some degree. If two different doses of venom never had the same molecular patterns then it would be impossible to immunize against it. A one-time supernova event would destroy a solar system, but the universe itself is antifragile to supernova…

Right. If you have systems that can adapt to stimulus in ways to prepare for recurring stimulus, you can look like this antifragile system. If the answer is to just be bigger... It is not a compelling model.

So building your immunity by using low doses doesn't mean you are antifragile. It means you are trainable. And even then, you are within tolerance levels. And cannot ever withstand some poisons.

Indeed, training is largely rehearsing some specific stimulus to be ready for it in a non training environment. We don't think of athletes as antifragile, though. Do we?

Re: Antifragility in complex dynamical systems

#110
post #97

Earlier quoted context omitted.

I mean you can go and argue with the biologists and economists if you need to. I'm just delivering the meesage.

My argument here would be that this isn't that new, all told? And... I would be shocked to find a lot of disagreement there. Indeed, other threads are already pointing out that terms already existed that covered this general idea. My problem with antifragile, as often offered, is that it is positioned as something that gets stronger from being damaged, full stop. But... there is literally nothing on earth that would…

There are limits. It's not about arbitrary negative stmuli and the entire idea only applies to certain kinds of systems. These criteria are covered in Taleb's books. The limits are well known in biology.
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