this is rather informal ofc, but if we wanted to quantify this a bit more...
obv we can't ever measure the actual "rate of change of the world", insofar as such a thing even has meaning, but we CAN arbitrarily select several of its assorted subsystems and sample them
oh and credit is due to @robinhanson for getting me to think about this idea in a much more useful way than any I'd heard previously
for the sake of this thread lets define "subsystem" as "some abstraction of phenomenon which can be sampled & quantified using a common methodology"
for ex, a country's economy, which is sampled using taxation/quarterly reports and quantified as the GDP (in prob wrong here)