This is an expanded excerpt from the emergence discussion from the Partially Examined Life Citizen Commons. We studied the classic More is Different: Broken Symmetry and the Hierarchical Nature of Science by P.W. Anderson. Their discussion software butchered my reply, so I figured I should clean it up by reposting it here.
It is difficult to have productive disagreements around “emergence” and “reductionism” because of the vague, confusing, and downright inconsistent way these terms are used. To help clear things up, I propose we talk in terms of the following levels.
- The Original Physical System. The actual thing “in and of itself” [what Kant said we couldn’t actually know] (e.g., water).
- The Theory of that System. A highly accurate model of that system, along with its “obvious” consequences (e.g., the atomic formula H2O).
- Emergent Properties. Phenomena that appear very different than the original characterization of the system, but can nevertheless be derived from it (e.g., snowflakes).
- Fundamentally Different Systems. New systems that appear to rest entirely on the original system, but whose relationship to it can not be formally derived from the theory (2) due to scale, complexity, or added context (e.g., the global water cycle).
- Designed Systems. A system built using components of the original system, yet whose structure reflects the influence of an external system (e.g., a ski slope).
From this perspective, “reductionism” is only of practical value between (2) and (3), and only of conceptual value in talking about (4). Reductionists who try to identify (1) and (4) in the same way as (2) and (3) are overreaching.
On the other extreme, we have creationists who equate (4) with (5) — and too often get away with it because their reductionist opponents who equate (4) with (3) are making equally-faith-based arguments!
The poster child for this sloppy use of terminology is the idea that “non-deterministic consciousness emerges from the interaction of deterministic atoms.” While most modern philosophers disagree with that claim, they disagree in very different ways:
- Compatibilism argues that consciousness is also deterministic, but unpredictable, so it feels non-deterministic.
- Panpsychism argues that atoms are non-deterministic, and that their non-determinism “emerges” in consciousness.
My sympathies are with the panpsychists, because compatibilists seem to be confusing the deterministic Bohr model (2) with the underlying non-deterministic quantum system (1). On the other hand, given our current understanding of the brain the panpsychic explanation doesn’t qualify as “emergent” as defined in (3), since we can’t demonstrate how quantum entanglement can exist at the scales necessary to influence neural activity.
Perhaps the best resolution at this point in time is to acknowledge that consciousness is a — at the moment — a “Fundamentally Different System”, and be humble about the fact that better theories (2) or derivations (3) may or may not show it to be emergent in the future.