An Approach to Constructing a Big History Complexity Ladder

The chapter begins by addressing the central role of complexity in big history, highlighting the lack of consensus on its definition and measurement. It argues that the nascent field of big history is enriched by diverse ideas, but this diversity also presents challenges in establishing a unified understanding of complexity. The text explores the tension between recognizing distinct thresholds of emergent complexity and the desire for a common measure, suggesting that different forms of complexity may require qualitatively distinct metrics. Drawing an analogy with the cosmological distance ladder in astronomy, the chapter proposes a complexity ladder that integrates multiple methods for measuring complexity across various scales. This ladder is designed to accommodate the overlapping and supervening nature of different forms of complexity, from fundamental particles to biological and social systems. The chapter also discusses the potential for a conventional interval scale to rationalize the complexity ladder, acknowledging the dialectic between metaphysics and measurement. It concludes by emphasizing the importance of reflective equilibrium in reconciling metaphysical and conventional aspects of complexity measurement, and the potential for the complexity ladder to evolve with new discoveries and technological advancements. The text also touches on the Great Complexity Discontinuity, highlighting the temporal and spatial gaps between global and local complexities, and the need for a more comprehensive understanding of complexity across the universe. It suggests that the complexity ladder can be extended into the future, integrating new forms of complexity as they emerge, and that the method of reflective equilibrium can be supplemented with the considered judgments of non-human minds, whether artificial or of other biological species.