How to understand the phrase "compact majorities" in this context?

I'm reading Emma Goldman's essay "Minorities versus Majorities" where she quotes Thomas Stockman saying

The most dangerous enemies of truth and justice in our midst are the compact majorities, the damned compact majority

This phrase "compact majority" appears in other parts of the essay, for example

The majority, that compact, immobile, drowsy mass, the Russian peasant, after a century of struggle, of sacrifice, of untold misery, still believes that the rope which strangles "the man with the white hands" brings luck

The only meanings of "compact" that I can find relate to "things packed closely together", but here it is used in a pejorative way, meaning, I guess, "ignorant"? Where does this come from?

The phrase you quote appears to be defining the term you are looking at:

The majority, that compact, immobile, drowsy mass...

I would assume that wherever else the author uses the phrase "compact majority" they are referring to this description.

Compact means "densely packed", but also carries connotations of "hard to break apart" "hard to move", which definitely tie in with the way the author is trying to describe the "majority". It doesn't necessarily mean ignorant, but it is intended to imply that their views don't change with new information or discoveries. "Immobile" and "drowsy" also convey similar ideas.

It could also mean "doesn't interact with those around", specifically that it is not informed by new information or discoveries.