The Epistemic Limits of Evolutionary Debunking: An Evaluation of Evolutionary Arguments Against Moral Realism

<p>Evolutionary debunking arguments contend that the evolutionary origins of moral belief undermine the epistemic standing of moral realism. Sharon Street's Darwinian Dilemma and Richard Joyce's genealogical undercutting argument represent the two most influential formulations of this challenge. This project subjects both to sustained internal critique and finds them wanting. The central contribution is a bridge-requirement framework identifying four principles (BR₁ through BR₄) that any evolutionary debunking argument must supply to move validly from genealogical premises to epistemic conclusions. BR₁ connects genealogy to justification. BR₂ connects population-level evolutionary explanations to individual-level epistemic consequences. BR₃ connects semantic features of moral discourse to differential epistemic vulnerability. BR₄ connects domain restriction to genealogical scope. Neither Street nor Joyce supplies adequate support for these requirements. A three-tier critique of each argument reveals convergent structural failures. At the foundational level, both arguments presuppose contested epistemological commitments without defending them and equivocate between population-level and individual-level claims. At the level of scope, a restriction failure argument demonstrates that the fitness-without-truth-tracking pattern grounding both arguments applies across mathematical, logical, modal, and epistemic domains, generating what this project identifies as a scope dilemma: debunkers must either defend a principled domain restriction or accept self-defeating global skepticism. At the level of transmission, three novel arguments concerning functional autonomy, post-hoc justification, and target restriction demonstrate that even granting the genealogical premises full force, the epistemic challenge they generate is narrower than claimed. The convergence of these failures across maximally different formulations indicates that the difficulties are not idiosyncratic but endemic to the project of deriving epistemic evaluations from causal genealogies without adequate philosophical bridges. The project concludes by sketching how each structural failure, when inverted, suggests a corresponding resource for a positive moral epistemology.</p>

Name thesis:degree_name

Philosophy, PhD

Level thesis:degree_level

Open Access Dissertation

Discipline thesis:degree_discipline

School of Arts and Humanities

Year dc:date.available

2026

Author dc:creator

• Guzmán, José Ernesto

Contributors dc:contributor

• Darrell Moore
• Philip Clayton

• Evaluative realism
• Evolutionary Debunking Arguments
• Genealogical defeat
• Moral epistemology
• Moral Realism
• Truth-tracking
• Philosophy
• Philosophy of Science

Repository record dc:identifier

https://scholarship.claremont.edu/cgu_etd/1102

OAI identifier oai:identifier

oai:scholarship.claremont.edu:cgu_etd-2124