Source
Flack (2017), LIT-1630, §6; read in NOTE-1216.
What was actually shown
Flack offers time-scale separation as one way a system can overcome the “inherent subjectivity” of noisy components with partial information (§6):
“If the time scale associated with a coarse-grained or aggregate variable is very slow compared to the microscopic behaviour producing it, it effectively becomes the ‘social’ environment (i say ‘social’ here to distinguish it from the exogenous environment, E we started with) and components can tune to it regardless of whether it actually does a good job of summarizing the regularities in E or now in M—think of social institutions that are highly constraining and very hard to change or the power distribution in the monkey case study. Time scale separation between M and S facilitates learning and hence coordinated and organized behaviour thereby minimizing the consequences of subjectivity due to noisy components with different windows on the world.”
The limit, in the next sentences: “it seems likely the system will fail at some point if the aggregate properties components rely on for prediction do not capture the regularities in M or E—failure may just take longer if the time scale separation is very large.” The macaque case is the one empirical anchor: “both the signalling network and power structure have a much slower time scale than the fight dynamics.”
This is an informal argument. No model is given, and no measured time scale for the slow variables. The claim about failure is hedged (“it seems likely”).
What this does not say
- That slowness makes an aggregate accurate. The point is the reverse: a slow aggregate can be followed when it is inaccurate.
- That separation alone makes the aggregate constrain. In Flack it constrains through components tuning to their estimates of it (§1); a slow variable no one tunes to is no downward causation.
- That separation is the only mechanism. Flack’s second is collective estimation (§6), which she calls “a somewhat trivial insight” in its averaging form.
- That organization makes separation. Flack’s only remark on the converse is an open question in §5: whether effective downward causation can “increase symmetries at the microscopic level” and make the system more amenable to coarse-graining.