Life as we know it

By Karl J. Friston. Journal of the Royal Society Interface, 2013

738 citations recorded by the source corpus.

This paper presents a heuristic proof (and simulations of a primordial soup) suggesting that life—or biological self-organization—is an inevitable and emergent property of any (ergodic) random dynamical system that possesses a Markov blanket. This conclusion is based on the following arguments: if the coupling among an ensemble of dynamical systems is mediated by short-range forces, then the states of remote systems must be conditionally independent. These independencies induce a Markov blanket that separates internal and external states in a statistical sense. The existence of a Markov blanket means that internal states will appear to minimize a free energy functional of the states of their Markov blanket. Crucially, this is the same quantity that is optimized in Bayesian inference. Therefore, the internal states (and their blanket) will appear to engage in active Bayesian inference. In other words, they will appear to model—and act on—their world to preserve their functional and structural integrity, leading to homoeostasis and a simple form of autopoiesis.

Subfields: Cognitive Neuroscience, Economics and Econometrics, Statistical and Nonlinear Physics

View Paper: https://www.semanticscholar.org/paper/9d91dead9612e1c6a8dd9ae3793fe697565c744e

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Cognitive Neuroscience

In Economics and Econometrics

In Statistical and Nonlinear Physics

Citations in the corpus

The graphical brain: Belief propagation and active inference (2017, background): “In this sense, the brain conforms to the imper-atives for all sentient creatures; namely, to restrict itself to a limited number of attracting states (Friston, 2013).”
Active interoceptive inference and the emotional brain (2016, background): “This shift recognizes alternative origins to ‘Bayesian brain’ ideas in 20 Century ‘cybernetics’ (14, 15) and in doing so, points to a deep connection between life and mind, in which cognitive processes are grounded in fundamental evolutionary imperatives to maintain physiological homeostasis (7, 16)”
How to Entrain Your Evil Demon (2017, background): “…out, this is basically a version of the pair of pendulum clocks described in the 1600s by Huygens’ (Huygens 1967, p. 185), which when hung from a beam in the right kind of set-up will eventually begin to swing synchronously even if separated by each their own Markov blanket (Friston 2013; Fig.”
Answering Schrödinger's question: A free-energy formulation (2017, neutral): “Recall from above that every ergodic system must possess an (ergodic) Markov blanket [32].”
The free energy principle made simpler but not too simple (2022, neutral): “It is often said that the free energy principle explains why biological systems resist the second law and a natural tendency to dissipation and disorder [96].”
The math is not the territory: navigating the free energy principle (2021, background): “…on what grounds they justify this assumption, beyond the further (unjustified) assumption that the aim of the modelling exercise must be realism and that “Friston (2013) seems to interpret the probabilities involved in FEP as objective features of realworld systems” (Colombo and Wright 2018).”
Active Inference, Curiosity and Insight (2017, background): “…and variational free energy is relatively straightforward to demonstrate using the Jarzynski equality (Jarzynski, 1997), which allows one to show that variational and thermodynamic free energy share the same minimum, in the limit of no sensory samples (Sengupta, Stemmler, & Friston, 2013).”
The anticipating brain is not a scientist: the free-energy principle from an ecological-enactive perspective (2016, background): “Friston claims that “an agent does not have a model of its world, [but rather] it is a model” (Friston 2013b).”
The free energy principle for action and perception: A mathematical review (2017, background): “These arguments have been developed in a series of papers which have appeared over the course of the last several years (Adams, Shipp, & Friston, 2013; Carhart-Harris & Friston, 2010; Friston, 2005, 2008a; Friston, Daunizeau, & Kiebel, 2009; Friston et al., 2010; Friston, FitzGerald, Rigoli,…”
Action and Perception as Divergence Minimization (2020, background): “In deterministic or homoskedastic environments, the input entropy is constant, so that matching τ ( x ) simpliﬁes to surprise minimization (Schrödinger, 1944; Friston, 2013; Berseth et al., 2019), where the agent seeks input trajectories x that maximize τ ( x ) .”
The Markov blankets of life: autonomy, active inference and the free energy principle (2018, background): “Friston KJ, Parr T, de Vries B. 2017 The graphical brain: belief propagation and active inference.”
How to Knit Your Own Markov Blanket (2017, background): “(Friston 2013, sect.”
A free energy principle for a particular physics (2019, methodology): “This is why we have previously asserted that the agent is (or entails) a generative model of its world – as opposed to possessing a generative model (Friston, 2013).”
Active Inference: A Process Theory (2017, methodology): “This separation of action and perceptual inference or state estimation can be understood by associating action with peripheral reﬂexes in the motor system that fulﬁll top-down motor predictions about how we move (Feldman, 2009; Adams, Shipp, & Friston, 2013).”
Situating the default-mode network along a principal gradient of macroscale cortical organization (2016, background): “The DMN is at a maximal distance from systems involved in perception and action in both functional connectivity and anatomical space, indicating that the neural activity in these regions is likely to be comparably insulated from direct environmental input (49, 50).”
Busting Out: Predictive Brains, Embodied Minds, and the Puzzle of the Evidentiary Veil (2017, background): “(K. Friston, 2013a) p. 32 This, I submit, is the primary locus for ‘self-evidencing’ in the PP/PEM story that: “takes the existence of agents as its starting point and concludes that each phenotype or agent embodies an optimal model of its econiche” (K. Friston, 2011) p.89 Hohwy, in the treatment…”