Sissa colloquium - Marcello Costa

A single physics: 7 steps from molecules to mind"

Abstract: 

The seminar will identify some of the crucial transitions between the appearance of atoms and molecules in the universe until the appearance of thinking beings such as homo sapiens. The idea is to link these transitions by conceptual steps that are consistent with modern science and that assume that atoms and thinking being exist in one world describable by a single comprehensive Physics. The proposal is of course not to invent a 'new Physics" but to extend the one well defined in modern science to include biological phenomena and the emergence of phenomenal experiences, without postulating the existence of a mythical irreducible gap separating the res extensa and the res cogitans.

In order to start on a simple and solid ground within the Newtonian/Einsteinian universe I will suggest as a first step that the definition of existence should imply a univocal relation between existing and being describable as having spatio-temporal coordinates.

The second conceptual step is that we should view structures formed since the big bang structures as having became stratified by a variety of processes of assembly of simpler elements into multiple levelled structures by selection processes and with emergence of new physical properties. Consequent to this perspective the 'rules' (processes) that govern the interchange of influences at every level are not likely to be the same as those that are involved in bottom-up and top-down influences across the various stratified layers.

The third simple step involves the simple acceptance from Physics of the laws of Thermodynamics and the relation between flow of energy in dissipative systems with local increase in order. The fourth step describes how even in the inorganic world, modern non linear dynamics describes the emergence of some transiently stable order and how even in a deterministic world future events cannot be necessarily predicted.

In such universe biological systems made their appearance, as fifth step, characterised by self assembled dynamic structures, usually enclosed in membranous compartments and maintained by processes of energy flow as dissipative systems which when become transmissible across individual organisms generated the evolutionary processes at least on Earth. Living cells with increasing degrees of coupling generated multicelullar organisms. Such organisms represent biological active media where each element act as a 'reaction' component and the spatial coupling the diffusion component of the well described equations that govern excitable cell properties and most biological phenomena.

The appearance of neural organisms endowed by sensory and motor capacity represents a sixth step in the emergence ladder. This event marked the appearance of distinct structures forming a functional loop between the 'external mechanical' world and the inner neural world. This transition couples the two aspects of the Cartesian dualistic world, one of kinetics, a world of mass in motion and an electrochemical world of neural states. This primordial sensory-motor loop acquires more prominent properties of circular causality and adaptation with degrees of stability of states.

The last step is the emergence, in evolution, of multiple superimposed neural loops that contribute to a gradual appearance of greater autonomy of such organisms with broadening of its 'horizon of existence. This process leads to the emergence of a sense of sentiency and agency culminating with the sense of being individuals with a will. As this emergence is associated to a high dependence on social life of the individuals, the emergence of the mental world is inseparable with that of social processes.

These scientifico-philosophical steps far from being controversial are based on broadly accepted grounding of modern knowledge and could be a useful path to navigate across disciplines and levels of complexity usually regarded too challenging by those who see science as threat to humanities or those who think that humanities could never be included under a same conceptual frame of knowledge.

More information about Marcello Costa: http://www.flinders.edu.au/people/Marcello.Costa

Location (SISSA room)