Urban policy design for antifragility

Abstract

Antifragility (Taleb 2012) is best understood in contrast to three other properties: fragility, robustness and resilience. Things inhabit disorder. Be they inanimate objects, systems, organisms or institutions, perturbations and unpredictable events of all sorts happen to them, around them and within them. To determine whether something is fragile, robust, resilient or antifragile means to examine how it responds and reacts to such perturbations.Something is fragile if it is prone to only harm over time. Events, stressors, volatility can only damage, break or destroy, and never benefit it. Not every event needs to be harmful. Rather, the above definition of fragility states two conditions which simultaneously need to hold: that there exists the possibility of only harm, and no gain from perturbations.Instead, something robust withstands perturbations unaffected; while something resilient is capable to absorb and recover from perturbations, to bouncing back to its original state or to its functional equivalent.Finally, antifragility is the proper opposite of fragility: something is antifragile when it can actually benefit from events, stressors and volatility: it can gain, get stronger, improve, evolve, better adapt. Analogous to fragility, not all perturbations need to be beneficial; some, perhaps most, may be inconsequential, but some can be -unlike in fragility robustness and resilience. Hence, antifragility goes beyond robustness and resilience since resilient or robust systems are merely perturbation-resistant, while antifragile systems not only withstand stress but can also benefit from it.We can view these four properties arranged on the harm-gain continuum, from fragility to robustness, resilience, and finally antifragility. This allows us to pinpoint the definitional distinction between resilience and antifragility: while both are responsive to perturbations, what sets them apart is the potential for gain from these perturbations, that is, none in resilience, some and possibly large in antifragility. Consequently, resilience should be seen as a 'limit case' of antifragility. Strictly, an urban (sub)system should be said to be resilient if it is capable of absorbing shocks, perturbations, volatility, to recover and