Progress, then, is not a "natural" fact, but a methodological one.
Under such circumstances it is utterly impossible from a methodological standpoint to regard them otherwise than identical.
Examine the methodological relations between Definition, Classification and Nomenclature.
Hence these principles carry their recommendation directly in themselves, and not merely as methodological devices.
A big part of the difference is methodological, rather than inherent in the nature of the phenomena themselves.
In Schumpeter's view, the division between statics and dynamics is much more than methodological.
If they turn out to be false, candour compels us to call them methodological fictions; but they continue in use.
The case of methodological assumptions is more difficult and instructive, and is usually misconceived.
That this is a methodological device no one denies, but so are most of the other distinctions that we frame.
But this, quite obviously, is merely a methodological precept, not a law of Nature.