Based on the provided sources, particularly the works of Pattee, Rosen, and Noble, the relationship between hierarchy, non-ergodicity, speciation, causality, and constraint can be untangled by viewing them as necessary components of a single explanatory framework for living systems.
Here is the synthesis of how these concepts interlock:
1. Non-Ergodicity: The Physical Context
The starting point is the recognition that biological systems exist in a non-ergodic universe.
• The Problem of Immensity: The “phase space” (the set of all possible states) of complex systems is so immense that a random (ergodic) search could never explore even a fraction of it. Life occupies a “zero volume” within this space; “almost all” possible configurations of matter are non-living[1].
• Irreducibility: Because living states are so rare and specific, the statistical averages used in physics (which assume ergodicity) cannot explain biology. You cannot understand an organism by averaging its states; you must understand the specific path it took to avoid the “dead” average[1].
2. Constraint: The Mechanism of Selection
To exist within this tiny “living” region of phase space without drifting back into disorder (the ergodic average), a system must limit its own behavior. This is achieved through constraint.
• Harnessing Laws: Constraints do not violate physical laws; they “harness” them. Pattee describes biological constraints as “non-holonomic” (flexible/rate-independent) structures that selectively limit the degrees of freedom of a system[2][3].
• Classification of Detail: A constraint works by ignoring most microscopic details (e.g., an enzyme ignores the speed of a substrate, recognizing only its shape). This “selective neglect” allows the system to simplify the chaotic physical world into functional categories[4][5].
• Arbitrariness: Unlike laws, which are universal and inexorable, constraints are local and arbitrary (e.g., the genetic code could have been different). They are “frozen accidents” that have become fixed because they successfully harness dynamics for survival[6][7].
3. Hierarchy: The Structure of Constraints
Constraints do not float freely; they are organized into hierarchies.
• Levels of Control: A hierarchy in biology is not just a stacking of blocks (structural hierarchy) but a system of authority (control hierarchy). The upper level acts as a constraint on the dynamics of the lower level[8][9].
• The Epistemic Cut: This hierarchy requires a separation between the description (symbol/gene) and the construction (matter/protein). This separation, called the “epistemic cut,” allows the upper level (the description) to control the lower level (the dynamics) without being destroyed by the chemical reactions it supervises[10].
• Simplification: The hierarchy functions by allowing the system to be described in simpler terms at higher levels. The complex dynamics of the lower level are treated as simple functions or “black boxes” by the level above[13][14].
4. Causality: The Flow of Control
Within this hierarchy, causality operates in two distinct directions, breaking the reductionist view of simple linear cause-and-effect.
• Upward Causation: The lower-level dynamics (chemical reactions, molecular forces) provide the power and material. This aligns with Aristotelian “material” and “efficient” causes[15][16].
• Downward Causation: The higher levels (the organism, the environment) exert downward causation by setting the boundary conditions for the lower levels. The organism determines which reactions occur and when by imposing constraints (like enzymes or membranes) on the chemistry[17].
• Circular Causality (Closure): Biological systems exhibit “closure to efficient causation” (Rosen). The organism produces the tools (enzymes) that metabolize the energy required to repair the organism. This circularity means the system is self-entailing; the “cause” of the system is the system itself[20][21].
5. Speciation: The Stabilization of Identity
Speciation is the result of these constraints and causal loops becoming “frozen” into a distinct, replicable identity.
• Discretization: In a non-ergodic world, stable existence requires distinct categories. Speciation is the process of creating a “discretization”—a stable, bounded set of constraints that defines a specific “self” separate from the environment[22].
• System Identity (Genome): Rosen identifies the “genome” not just as DNA, but as the set of constitutive parameters that define the “species” of a system. Speciation occurs when these parameters change, altering the system’s identity and its causal relationship with the environment[23][24].
• Semantic Closure: A species is defined by “semantic closure”—a closed loop where the symbolic instructions (genes) define the physical constraints (enzymes), and the physical constraints interpret the instructions. This closure locks the system into a specific, heritable trajectory through the non-ergodic phase space[25][26].
Summary of the Relationship
• Non-ergodicity creates the threat of dissolution into disorder.
• Constraints provide the foothold against this threat by limiting freedom.
• Hierarchy organizes these constraints into levels of control (laws vs. rules).
• Causality (specifically downward and circular) is the mechanism by which the hierarchy operates (boundary conditions controlling dynamics).
• Speciation is the stabilization of a specific hierarchy of constraints into a distinct, self-maintaining identity (a closed causal loop).
References
[1] [Book] Rosen - Anticipatory Systems Philosophical Mathematical and Methodological Foundations.pdf [2] Howard Pattees Theoretical biology a radical epistemological stance to approach life evolution and complexity.pdf [3] Pattee - Physical Basis and Origin of HierarchicaL Control.pdf [4] Pattee - Physical Basis and Origin of HierarchicaL Control.pdf [5] Pattee - Physical Basis and Origin of HierarchicaL Control.pdf [6] Pattee - Physical Basis and Origin of HierarchicaL Control.pdf [7] [Book] Pattee - Laws Language and Life Howard Pattee’s classic papers on the physics of symbols with contemporary commentary.pdf [8] Pattee - Physical Basis and Origin of HierarchicaL Control.pdf [9] Pattee - Physical Basis and Origin of HierarchicaL Control.pdf [10] Irreducible and complementary semiotic - Howard Pattee.pdf [13] Pattee 2012 unsolved problems and potential applications of hierarchy theory.pdf [14] [Book] Pattee - Laws Language and Life Howard Pattee’s classic papers on the physics of symbols with contemporary commentary.pdf [15] Noble - Biological circular causality but not symmetry of causation so where what and when are the boundaries.pdf [16] [Book] Rosen - Anticipatory Systems Philosophical Mathematical and Methodological Foundations.pdf [17] Noble - Biological circular causality but not symmetry of causation so where what and when are the boundaries.pdf [20] louie - rosen relational diagrams of living systems.pdf [21] louie - rosen relational diagrams of living systems.pdf [22] Pattee and Kull - A biosemiotic conversation.pdf [23] [Book] Rosen - Anticipatory Systems Philosophical Mathematical and Methodological Foundations.pdf [24] [Book] Rosen - Anticipatory Systems Philosophical Mathematical and Methodological Foundations.pdf [25] [Book] Pattee - Laws Language and Life Howard Pattee’s classic papers on the physics of symbols with contemporary commentary.pdf [26] [Book] Pattee - Laws Language and Life Howard Pattee’s classic papers on the physics of symbols with contemporary commentary.pdf