Notes on Complexity: A Scientific Theory of Connection, Consciousness, and Being

Neil Theise's 2023 trade book is the place to read for the intellectual frame within which the 2018 interstitium paper's not an organ — a system characterisation makes sense. Theise has been writing about complexity theory, emergence, and the body-as-continuous-system across pathology and consciousness studies for two decades; the 2023 book is the synthesising trade statement of that long-running parallel programme. Published by Spiegel & Grau in May 2023, 224 pages; named one of The Marginalian's Best Books of 2023, 2024 Nautilus Book Award winner.

The book threads three substantive sources: contemporary complexity-science literature (emergence, scale-free networks, self-organising criticality), Theise's clinical-pathology career including the interstitium work and his earlier adult-stem-cell-plasticity work, and his long-running Zen Buddhist practice. The argument is that biological and physical systems at every scale exhibit emergent, irreducible coherence that the discrete-entity vocabulary of conventional textbook biology imperfectly captures, and that the interstitium — continuous, fluid, hard to categorise as organ or non-organ — is one specific case of a more general phenomenon.

The piece sits as a trade-book synthesis, not a primary scientific report. It is the place to read for why the framing of the 2018 paper as a system rather than an organ was natural to its pathology lead, and for the broader programme of which the interstitium work is one episode. The book has been praised by Maria Popova and Deepak Chopra; the more academic philosophical-science reception has been more mixed, with concerns about how the Eastern-philosophy synthesis interacts with the empirical claims.

The stake is intellectual and reputational. Theise is a respected pathologist with a substantial primary-literature record; the trade book trades on that record while extending into territory (consciousness, panpsychism-adjacent metaphysics, Buddhist philosophy) that is not strictly inside his clinical-research expertise. Notes on Complexity is a serious essayistic synthesis from a working scientist whose intellectual range is wider than the journal literature reveals, though the metaphysical claims are not the same species as the anatomical ones. Read it for the frame; read the 2018 paper for the anatomy.