The way you define “real” properties, it seems you can’t tell them from “unreal” ones by looking at correlations alone; we need causal intervention for that, a la Pearl. So until we invent tech for modifying dendrite density of living humans, or something like that, there’s no practical difference between “real” g and “unreal” g and no point in making the distinction between them. In particular, their predictive power is the same.
So, basically, your and Shalizi’s demand for a causal factor is too strong. We can do with weaker tools.
The way you define “real” properties, it seems you can’t tell them from “unreal” ones by looking at correlations alone; we need causal intervention for that, a la Pearl. So until we invent tech for modifying dendrite density of living humans, or something like that, there’s no practical difference between “real” g and “unreal” g and no point in making the distinction between them. In particular, their predictive power is the same.
So, basically, your and Shalizi’s demand for a causal factor is too strong. We can do with weaker tools.