For Biological Systems, Maintaining Essential Variables Within Viability Limits is Not Passive

Abstract

Open peer commentary on the article “Homeostats for the 21st Century? Simulating Ashby Simulating the Brain” by Stefano Franchi. Upshot: The target article proposes that Ashby’s investigations of the homeostat and ultrastability lead to a view of living systems as heteronomous, passive “sleeping” machines and thus are in fundamental conflict with concepts of autonomy developed by Jonas, Varela and others. I disagree, arguing that (1) the maintenance of essential variables within viability limits is not a passive process for living systems and (2) the purpose of Ashby’s investigations of the homeostat was to investigate adaptivity, a subject that is related to, but clearly distinct from, autonomy. As such, I find Ashby’s work on adaptivity to be neither in opposition to nor in direct support of modern concepts of biological autonomy and suggest that a productive way forward involves the investigation of the intersection between these two fundamental properties of living systems.