Einstein Was Not a Flat Physicalist: Principle Theories, Constructive Theories, and the Direction of Constraint

TL;DR

The paper addresses the misapplication of Einstein's principle–constructive distinction in defending Flat Physicalism, notably in Hemmo and Shenker's work. It reconstructs Einstein's distinction from primary sources, emphasizing its constraint-based logic and epistemic asymmetry. The analysis shows that reversing the hierarchy—treating principle theories as explananda and microphysical theories as ontologically fundamental—misreads Einstein and clashes with modern physics across thermodynamics, the arrow of time, mental causation, and quantum foundations. It argues that macroscopic regularities are genuine constraint structures, not merely descriptions to be reduced, and advocates a structural physicalism that preserves principle-level constraints in harmony with contemporary physics and Einstein's methodology.

Abstract

Einstein's distinction between principle theories and constructive theories is methodological rather than metaphysical. Principle theories such as thermodynamics and relativity articulate empirically distilled constraints that delimit admissible microphysical models, while constructive theories remain provisional and revisable. This paper reconstructs Einstein's framework from primary sources and argues that recent appeals to it by Meir Hemmo and Orly Shenker (under the banner of "Flat Physicalism") invert its functional hierarchy. What is presented as an Einsteinian template instead supports a reductionist metaphysics foreign to Einstein's methodology and increasingly misaligned with the structural commitments of contemporary physics.