José Ortega y Gasset was a 20th-century Spanish philosopher still known for his theory of the mass-men (including mass-women if it is necessary to add). My Regulation review of his 1932 The Revolt of the Masses (1930 for the original Spanish edition) suggests that, despite some oddities or errors, Ortega can be read as a philosopher in search of liberalism.

For Ortega, the mass-man is the person who is blind to the conditions necessary for the maintenance of a liberal civilization. To quote a few passages of my review:

Mass-men are those “for whom to live is to be every moment what they already are, without imposing on themselves any effort towards perfection.” It should be noted this is not class theory. Ortega makes clear that we often see “nobly disciplined minds” in working classes, while in the upper classes of surviving nobility and among intellectuals we frequently find “the mass and the vulgar.”

Ortega’s mass-men seem to prefigure the obscurantist era that
we seem to be entering today. The mass-man is not interested in
the conditions of civilization, even in the conditions of science,
which provides him with “his motor-car … but he believes that it
is the spontaneous fruit of an Edenic tree.” He is like a primitive
with no knowledge of history and who cannot but repeat mistakes
of the past.

Ortega considers the typical scientist as “the prototype of the mass-man”:

Science is essential, of course: “China reached a high degree of technique without in the least suspecting the existence of physics,” he writes. “It is only modern European technique that has a scientific basis, from which it derives its special character, its possibility of limitless progress.” But science requires narrow specialization. Thus, the scientific man has no culture. Contrary to Einstein, “who needed to saturate himself with Kant and Mach before his own synthesis,” the typical scientific man is “astoundingly mediocre, and even less than mediocre.” He is “a learned ignoramus.” Perhaps a good example in our own days is the public health expert. (See “The Dangers of ‘Public Health,’” Fall 2015.)

We may wonder if many if not most economists aren’t also mass-men.