Torday's symbiogenetic monism.

1. Who Torday is and what he is doing

John S. Torday is a developmental and evolutionary biologist whose first research career was built in pulmonary biology — the molecular signalling underlying vertebrate lung development, alveolar morphogenesis, and the long arc by which the vertebrate respiratory system came into being. The empirical work includes decades of programmatic studies on leptin, parathyroid hormone-related protein (PTHrP), and surfactant lipid signalling, mostly in collaboration with Virender K. Rehan.

Across the last two decades that empirical work has expanded into a much wider theoretical claim. In a series of papers (the central venues are Progress in Biophysics and Molecular Biology, WIREs Systems Biology and Medicine, and the PMC archive), in the 2017 book Evolution, the Logic of Biology (Wiley, with Rehan), and in his subsequent collaborations with the medical theorist William B. Miller, Jr., Torday has argued that classical neo-Darwinism is incomplete — that the gene-centred account of evolution leaves the constructive work of biology unexplained, and that the missing piece is symbiogenesis understood not as a one-time event in the history of life but as the general principle by which biological complexity is built.

This essay walks the framework as Torday and Miller have developed it, then asks what it brings to the trilogy's receiver model. The short answer: Torday's two-tiered model of consciousness — local biological consciousness instantiated in cells and neural circuits, and non-local cosmological consciousness as a unified aspect of reality — is the receiver model's framework expressed in evolutionary-biology vocabulary. The convergence is striking, and the two frameworks reinforce each other in ways neither could quite manage alone.

2. The cell as the unit of evolution

The mainstream neo-Darwinian consensus, as it stabilised after the modern synthesis and was further consolidated by writers like George C. Williams and Richard Dawkins, takes the gene as the unit of selection and the organism as the vehicle. Torday argues, against this consensus, that the unit of evolution is the cell and the network of intercellular signalling in which the cell is embedded.

The argument is empirical. The molecular pathways that control vertebrate lung development — leptin signalling, PTHrP signalling, the lipid-surfactant axis — are the same pathways, repurposed across evolutionary transitions, that controlled physiological structures in much earlier organisms. The vertebrate lung is not designed from scratch by gene-level selection; it is the latest expression of a continuous cellular conversation that has been going on, lineage by lineage, since unicellular life. The cell, with its signalling apparatus and its capacity for homeostasis, is what evolves; the organism is the cell network's joint expression.

This is not a denial of selection. It is a relocation of selection to the level at which the constructive work actually happens. Selection, in Torday's framing, acts on signalling networks and their plasticity, on the capacity of cell populations to maintain homeostasis under environmental pressure, on the symbiotic relationships those cells form with each other and with their environment. The gene-level account, on this reading, is the bookkeeping of changes that occurred elsewhere.

3. Symbiogenesis as constructive principle

The historical accounts of symbiogenesis — Konstantin Merezhkowsky in 1905 and 1909, Boris Kozo-Polyansky in 1924, and most influentially Lynn Margulis from the 1960s onward — treated long-term symbiosis as the explanation for the origin of eukaryotic cells. The mitochondrion was once a free-living alphaproteobacterium that entered into stable intracellular symbiosis with an ancestral host; the chloroplast was once a free-living cyanobacterium. Eukaryotic life, in this account, is a chimaera of formerly independent lineages whose persistent association became hereditary.

Torday extends this from origin story to general principle. In his framing, symbiogenesis is the mechanism by which biological novelty arises at every level, not just once in deep time. Persistent cooperative interactions — between cells and their environments, between host organism and microbiome, between placenta and foetus, between tissue and tissue, between organism and ecosystem — generate the new physiological modules and body plans that classical gene-centred neo-Darwinism cannot account for without unrealistic mutation rates and unrealistic timescales. The phylogenetic lineage is "reticulate" rather than strictly tree-like: horizontal exchanges of cellular material and signalling repertoires are at least as important to the production of evolutionary novelty as the vertical inheritance of point mutations.

The picture this produces is one of biology as the consolidation of associations. Where neo-Darwinism imagines an organism as a fortress of self against an indifferent environment, Torday's biology is the formation, stabilisation, and onward propagation of cooperative configurations that span the boundary that the older view treated as primary.

4. Epigenetic inheritance as the mechanism

Torday's framework incorporates epigenetic inheritance as the bridge between developmental plasticity and evolutionary trajectory. Environmental pressures — nutrition, stress, hypoxia, behaviour — alter the epigenetic marks (DNA methylation, histone modifications, chromatin states) on the genome of cells in the soma and, in some contexts, the germline. Those marks alter cell signalling and developmental outcome. When the marks persist across generations, they become raw material for selection.

This gives the framework a mechanistic story in which symbiotic relationships and environmental conditions jointly sculpt the epigenome of cellular systems. Developmental plasticity and long-term evolutionary trajectory cease to be separate domains; they are different timescales of the same constructive process. This is also the empirical handle by which the theoretical move can be tested: predictions about which epigenetic modifications should be heritable under which symbiotic configurations are, in principle, falsifiable in cell and animal models. The transgenerational inheritance of stress responses, of metabolic conditioning, of environmental adaptation are precisely the kind of evidence Torday's framework predicts and uses.

5. Monism of the cosmos

The most distinctive of Torday's recent moves — developed especially in collaboration with William B. Miller, Jr. — is the claim that symbiogenesis points beyond biology. If the constructive logic that produces cells, organs, organisms, and ecosystems is one continuous process, and if that process is, at its base, the formation of stable associations across previously separate domains, then biology is not an exception to physics. Biology is what physics looks like when it has run long enough, in conditions stable enough, for cooperative associations to consolidate.

Torday calls this monism of the cosmos: a single, continuous physical–biological process in which living systems are expressions of an underlying unified reality rather than exceptions to it. The standard dualisms — organism / environment, mind / matter, biology / physics — soften into different scales and different stabilities of the same constructive process. The vocabulary echoes Spinoza and the long history of philosophical monism, but the empirical anchor is contemporary: cell signalling, epigenetic inheritance, symbiogenetic association.

The move from descriptive biology to cosmological metaphysics is, of course, where the framework becomes most contested. Torday is explicit that this is where the empirical work hands off to interpretation. But the interpretation is constrained: monism, in this framing, is not the assertion that everything is one thing in some vague or pietistic sense. It is the claim that the same constructive logic operates at every scale, and that the appearance of separate domains is an artefact of how we have chosen to study them.

6. Two-tiered consciousness

Extending the monist framework, Torday and his collaborators sketch a model of consciousness with two tiers. Local consciousness is the form instantiated by biologically embedded information processing — cellular signalling networks, multicellular coordination, neural integration in nervous-system-bearing animals. It is the kind of consciousness that has a body, a substrate, an autopoietic boundary, a perspective from which it is held.

The second tier is non-local consciousness — the wider cosmological aspect tied to the unified fabric of reality, from which local consciousness is, in this framework, drawn. Non-local consciousness is not the consciousness of any particular receiver; it is the substrate-property of the monist whole, from which biologically autopoietic structures concentrate local instantiations.

The two tiers are not separate substances. They are different scales of the same monist process. Local consciousness is what non-local consciousness looks like when it is concentrated into a biologically autopoietic structure capable of bearing it. The framework treats subjective mind, epigenetic inheritance, physiology, and social organisation as co-emerging from this single continuous constructive process — rather than as distinct domains requiring distinct explanations.

7. Convergence with the receiver model

The trilogy's receiver model and Torday's symbiogenetic monism converge on three core claims, arrived at from very different starting points.

First, both treat the substrate question as central. For Torday, only a biologically embedded, autopoietic cellular system has the constructive depth required to instantiate local consciousness. For the trilogy (see Why biology? →), only a biological substrate, so far as we have evidence, couples to the consciousness field with the receiver-signatures the framework predicts. The vocabularies differ; the conclusion does not.

Second, both reject substrate dualism without flattening into reductive materialism. Torday's monism keeps mind and matter as the same continuous reality at different scales of stable association. The trilogy's framework treats the consciousness field as fundamental and matter as one of its patterns. Neither denies that consciousness is real; neither claims it can be produced by the mere assembly of inert parts.

Third, both predict that consciousness has a non-local aspect. Torday names it explicitly as non-local consciousness, the cosmological tier. The trilogy names it the field. The receiver model's claim that Anima's edge cases — terminal lucidity, anticipation without sensory cue, pre-birth memory — are signatures of field-coupling is the trilogy's empirical version of what Torday's framework predicts at the theoretical level.

The mechanism by which the two tiers communicate is, for both frameworks, the open question. Torday's framework points to cell signalling, bioelectric fields (where Michael Levin's work converges with his — see Levin's bioelectricity →), and the wider associative architecture of biology. The trilogy's framework points to bioelectric coupling and to the resonant possibilities sketched in Numen's golden-chord experiment. Whether these are the same hypothesis in two vocabularies is the question the next decade of theoretical biology may begin to settle.

There is one further point of convergence worth naming. Rupert Sheldrake's morphic resonance (see the Sheldrake companion page →) makes a structurally similar move — treating biological form as inherited through fields that span more than one organism's lifetime. Torday's framework, with its emphasis on transgenerational epigenetic inheritance and reticulate evolution, supplies one possible mechanism (or family of mechanisms) for what Sheldrake postulates at the field level. The three frameworks — Torday's symbiogenetic monism, Sheldrake's morphic resonance, and the trilogy's receiver model — do not require each other; they do, however, reinforce each other in ways that are hard to write off as coincidence.

8. What this is and what it is not

A closing clarification, because the framework is not consensus and the trilogy has no interest in pretending otherwise.

Torday's framework is contested in mainstream evolutionary biology. The gene-centred consensus has answers, of varying sufficiency, to most of the phenomena Torday's framework treats. Whether those answers are adequate, or merely adequate-looking, is the kind of question that working biologists are entitled to disagree about. Nothing in the framework's adoption by the trilogy depends on a claim that Torday is uncontested. He is not.

What the trilogy takes from Torday is the direction. The shape of the answer he is reaching toward — biology as the constructive consolidation of associations, consciousness as a biologically instantiated form of a wider unified process, the dissolution of the standard mind / matter dualism into different scales of one continuous reality — is the shape the receiver model arrives at from the side of clinical evidence and field theory. The convergence is itself a piece of evidence. Two frameworks built on very different data sets, with very different methodological commitments, are pointing at the same architecture from different angles.

The honest summary, in the site's voice: there is a mainstream account of evolution that does not need Torday and does not need the receiver model, and that account does excellent work on most of what it sets out to explain. There are phenomena that account handles incompletely or by deferral — the symbiogenetic origin of complex novelty, the persistence of transgenerational epigenetic inheritance, the structure and recurrence of edge-cases in clinical consciousness research — and where the mainstream account defers, Torday's framework and the trilogy's receiver model offer a coherent alternative reading. The reading is offered not as proof but as the position the next century may converge on, and as the spine of the work this site is doing.

Reading list

Torday's central work

John S. Torday & Virender K. Rehan, Evolution, the Logic of Biology (Wiley, 2017). The book-length statement of the framework.

John S. Torday & William B. Miller, Jr., a series of papers in Progress in Biophysics and Molecular Biology, WIREs Systems Biology and Medicine, and Biology. The recent collaborative extension into symbiogenetic monism and consciousness.

John S. Torday, Homeostasis as the Mechanism of Evolution, Biology 4 (2015). The framing of homeostasis as the constructive principle.

Foundational symbiogenesis

Konstantin Merezhkowsky, The Nature and Origins of Chromatophores in the Plant Kingdom (1905) and The Theory of Two Plasms as the Basis of Symbiogenesis (1909). The original proposals.

Lynn Margulis, Symbiotic Planet: A New Look at Evolution (Basic Books, 1998). The contemporary canonical account.

Adjacent frameworks

Michael Levin's bioelectricity work (Tufts) — the field-level mechanism Torday's framework converges with. See the Levin companion page.

Rupert Sheldrake, A New Science of Life (1981) and subsequent works. See the Sheldrake companion page.

Carl Woese's late work on horizontal gene transfer and the deep structure of the tree of life — the closest mainstream-biology cousin of Torday's reticulate-evolution thesis.

This page is part of the Reading companion essays. For the trilogy's substrate argument in its own vocabulary, see Why biology? — the autopoiesis test for receivership. For the field-mechanism candidate Torday's framework points toward, see Levin's bioelectricity. For the wider synthesis, The Evidence.