Defending Bayes, Part 9 (Interlude)

Series: Defending Bayes (Part 9 - Interlude)

Summary

Critical conceptual clarification distinguishing Measure (objective physical probability) from Credence (subjective epistemic uncertainty). Both follow probability axioms but differ fundamentally in interpretation.

Key Concepts:

Measure:

• Objective physical probability embedded in reality structure
• Independent of observers or beliefs
• Intrinsic probabilities from physical laws and quantum mechanics
• Example: Branch weights in QBU framework

Credence:

• Entirely subjective
• Quantifies epistemic uncertainty—rational confidence given incomplete knowledge
• Applies to theories, logical propositions, conceptual frameworks, models
• Does NOT imply theories have “partial correctness” objectively

Why the Distinction Matters:

• Prevents confusion of credence as intrinsic property of theories (Deutsch-Hall’s critique)
• Reinforces Conditionalism (truth claims meaningful only within frameworks)
• Ensures coherent use of probabilities in decision theory (EDT)

Central Insight: Probabilities follow mathematical rules, but knowing whether we mean objective Measure or subjective Credence profoundly affects reasoning and interpretation.

Tags

• epistemology
• probability
• bayesian
• quantum
• philosophy-of-science
• decision-theory
• conditionalism
• sequence

Cross-References

• Backward: Defending Bayes, Part 8
• Related: Defending Bayes, Part 8
• Related: QBU framework
• Related: Effective Decision Theory
• Related: Conditionalism
• Related: Deutsch-Hall critique

Notes

• Labeled “Interlude”—meta-level conceptual clarification
• Provides crucial vocabulary for subsequent philosophical work
• Measure/Credence distinction becomes standard terminology in axionic philosophy
• Published same day as Part 8—sequential clarifications
• Brief but foundational—establishes linguistic precision for future work