The literature on reasoning is among the oldest in philosophy and among the most active in the cognitive sciences. The framework engages the principal positions by name; each is taken up again at [§8.4.5](<8.4.5 What is Concluded.md>) once the structural account is in view.

*The classical-faculty tradition.* Plato (*Republic* IV) placed reason at the top of the soul's hierarchy, organizing appetite and spirit beneath it; Aristotle (*Nicomachean Ethics* I.7) named *logos* the activity that characteristically defines human life, and (*Prior Analytics*) located the structure of valid inference in the syllogism. The faculty-psychology tradition Descartes (1641) refined and Kant (1781) restructured continues to organize popular and much philosophical conception of reason as a distinct higher capacity. The framework's reading is that the faculty-psychology language tracks something real, the recursive operation that takes one's own holdings as the thing being operated on, but misreads its location: reasoning is not a faculty above the body but the same recursion that runs in registration and feeling, at the depth where it has begun to operate on what it has registered.

*Hume's reason-as-slave.* Hume's (1739) claim that reason is and ought only to be the slave of the passions inverts the classical hierarchy by making registration prior to reasoning and reasoning subordinate to it. The position has had continuing influence in meta-ethics (Williams 1981; Smith 1994) and motivational psychology. The framework reads Hume as correctly identifying that registration is prior to reasoning, while misreading the priority as subordination: registration without the recursive fold that tests it does not yet rise to reasoning.

*Kant's transcendental architecture.* Kant (1781, 1788) restored reasoning's autonomy without restoring the soul-hierarchy, distinguishing theoretical from practical reason and locating the categories that make reasoning possible at all in a transcendental architecture overlaying experience. The position has had immense continuing influence in epistemology, philosophy of mind, and ethics. The framework reads Kant as correctly identifying that reasoning has its own structure, while locating that structure in what the medium itself permits, registered from inside the recursion that runs against the medium's constraints, not in a transcendental architecture supplied by the subject.

*Formal and inferential traditions.* Frege (1879) and Russell (1903) recovered the formal structure of valid inference and made deduction precise; Peirce (1903) widened the inventory beyond deduction to include abduction and induction as distinct operations the same recursion can run. The formal tradition continues in contemporary logic and decision theory. The framework treats these accounts as accurate at the level of inference-pattern recognition while supplying the deeper claim: what makes valid inference valid is the medium's constraints being followed correctly, not the formal pattern hovering independent of anyone running it.

*Dual-process theories.* Kahneman and Tversky's (1974) heuristics-and-biases program, Kahneman's (2011) *Thinking, Fast and Slow*, Evans (2008), and Stanovich (2011) developed dual-process accounts on which two cognitive systems operate: System 1 (fast, intuitive, affective) and System 2 (slow, deliberate, analytic). The position has been highly influential in psychology, behavioral economics, and policy. The framework reads dual-process accounts as picking up the depth-gradient structure of recursion (shallower registration-and-pattern-matching and deeper test-and-follow-out) while denying the categorical two-system reading: there is one recursive activity at multiple depths, not two systems.

*Bayesian and probabilistic accounts.* Bayesian epistemology and the predictive-processing tradition (Tenenbaum et al. 2011; Friston 2010; Clark 2016) treat reasoning as the optimization of probabilistic beliefs given evidence. The accounts have been highly successful at explaining specific cognitive phenomena: perception, learning, motor control. The framework's reading is that probabilistic update is one operation reasoning runs, important and pervasive, but not the whole of reasoning: deductive following-out of necessities, abductive inference to best explanation, and reflective examination of one's own holdings are not exhaustively probabilistic.

*Ecological and bounded rationality.* Gigerenzer (1999, 2007) and the broader ecological-rationality program argue that heuristics, often dismissed as biases, are well-adapted strategies given the structure of the environments organisms face. Simon's (1957) bounded-rationality tradition predates and frames the position. The framework's reading aligns with the ecological-rationality view: reasoning is the being's commerce with necessity *as it can be approached* given the resources the being has, with heuristic strategies often well-fitted to the structure they operate within.

*Bayesian rationality and disagreement.* A live literature (Christensen 2007; Kelly 2010; Elga 2007) investigates how rational agents should respond to disagreement among epistemic peers and how reasoning relates to evidence. The framework treats this as one face of the broader question what the medium's constraints permit two beings to conclude from shared evidence; disagreement among careful reasoners is structurally possible at the limits the medium's underdetermination allows, and the framework neither requires nor forecloses convergence as a general norm.

*Eliminativism about folk rationality.* As with consciousness and drive, a small literature (P. M. Churchland 1986; some contemporary cognitive-science programs) argues folk-psychological talk of reasoning will be eliminated. The framework's response, parallel to its earlier responses: reasoning is the activity that can fail by the medium's constraints (a real activity, not a folk illusion) and the mature description will identify rather than eliminate it.

The literature on reasoning divides over faculty-psychology vs continuous-recursion accounts, Hume's priority claim, Kant's transcendental architecture, formal-inferential accounts, dual-process theories, Bayesian and ecological-rationality programs, peer disagreement, and eliminativism about folk rationality. The framework commits to specific answers on each; they are taken up again at [§8.4.5](<8.4.5 What is Concluded.md>) after the structural account is in view.


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← [8.4 Reasoning](<8.4 Reasoning.md>) | [8.4.2 What is Required](<8.4.2 What is Required.md>) →
