Strong Emergence Arising from Weak Emergence

Abstract

Predictions of emergent phenomena, appearing on the macroscopic layer of a complex system, can fail if they are made by a microscopic model. This study demonstrates and analyses this claim on a well-known complex system, Conway’s Game of Life. Straightforward macroscopic mean-field models are easily capable of predicting such emergent properties after they have been fitted to simulation data in an after-the-fact way. Thus, these predictions are macro-to-macro only. However, a micro-to-macro model significantly fails to predict correctly, as does the obvious mesoscopic modeling approach. This suggests that some macroscopic system properties in a complex dynamic system should be interpreted as examples of phenomena (properties) arising from “strong emergence,” due to the lack of ability to build a consistent micro-to-macro model, that could explain these phenomena in a before-the-fact way. The root cause for this inability to predict this in a micro-to-macro way is identified as the pattern formation process, a phenomenon that is usually classified as being of “weak emergence.” Ultimately, this suggests that it may be in principle impossible to discriminate between such distinct categories of “weak” and “strong” emergence, as phenomena of both types can be part of the very same feedback loop that mainly governs the system’s dynamics.

Complexity, Artificial Life, and Artificial Intelligence

“…For complexity, a relevant case is that of emergence [1,14,16,97] (to be expanded in Section 6). There are several notions and flavors of emergence.…”

Is information the other face of causation in biological systems?

“…Ultimately, the crucial feature to discriminate between weak emergence and strong emergence is downward causation (Kim 1999). Otherwise the philosophical debate about their large-scale properties and the predictive power of lesser scales would lead us to a conclusion that the difference between the weak and strong forms of emergence may be in principle impossible (Corning 2012;Schmickl 2022). The CEP rejects downward causation and, hence, holism based on strong emergence, but not on weak emergence.…”

“…Its elementary basis resides at the molecular scale where emergent self-organization originates ultimately from Brownian motion. Only on the assumption that information flow within these biological hierarchies had causal power, weak (epistemic) emergence, based exclusively on predictive power, could be turned into its strong (ontological) counterpart to account for downward causation (Schmickl 2022;Farnsworth 2022).…”

Is information the other face of causation in biological systems?

“…Its elementary basis resides at the molecular scale where emergent self-organization originates ultimately from Brownian motion. Only on the assumption that information flow within these biological hierarchies had causal power, weak (epistemic) emergence, based exclusively on predictive power, could be turned into its (ontological) counterpart to account for downward causation (Schmickl 2022;Farnsworth 2022).…”