True complexity and the natures of existence

My concern in this chapter is true complexity and its relation to physics. This is to be distinguished from what is covered by statistical physics, catastrophe theory, study of sand piles, the reaction diffusion equation, cellular automata such as “The Game of Life,” and chaos theory. Examples of truly complex systems are molecular biology, animal and human brains, language and symbolic systems, individual human behavior, social and economic systems, digital computer systems, and the biosphere. This complexity is made possible by the existence of molecular structures that allow complex biomolecules such as RNA, DNA, and proteins with their folding properties and lock-and-key recognition mechanisms, in turn underlying membranes, cells (including neurons), and indeed the entire bodily fabric and nervous system.

True complexity involves vast quantities of stored information and hierarchically organized structures that process information in a purposeful manner, particularly through implementation of goal-seeking feedback loops. Through this structure they appear purposeful in their behavior (“teleonomic”). This is what we must look at when we start to extend physical thought to the boundaries, and particularly when we try to draw philosophical conclusions – for example, as regards the nature of existence – from our understanding of the way physics underlies reality.

Arbiter and peacemaker

Agnes Clerke in her sixties had become a sort of mother figure among astronomers, tactful, kind, helpful. The sour comments of R.A. Gregory in Nature, about which she never complained, appear to have been the only shadow on her blameless life. She kept her balance in the dispute between Huggins and Lockyer without offending either, and subscribed to the superiority of the American spectroscopists without offending the Hugginses. A glimpse of her in the role of peacemaker is found in her correspondence in 1904 with W.W. Campbell of Lick, a man who in his youth was not afraid to stand up for himself against acknowledged ‘authorities’ (Huggins being one) if he knew his work was better. There was a long-running difference of opinion between him and Huggins about the spectra of the Orion Nebula and the Orion trapezium stars. He also challenged the Hugginses' view, repeated in their recently published Atlas, that the Orion Nebula was variable. Campbell was now returning to the subject, and in a less aggressive mood than formerly sent a copy of his manuscript to Huggins before publishing. He placed the matter before Agnes Clerke, explaining that the reason for the differences between his observations and those of Huggins over the years was instrumental. Agnes Clerke replied that ‘no-one, least of all Sir William Huggins, will be likely to misconstrue the spirit of entire loyalty to science in which it [i.e. your investigation] has been conducted’.