The passionate controversies of one era are viewed as sterile preoccupations by another, for knowledge alters what we seek as well as what we find.

Adler is pointing to the way intellectual and moral urgency is historically contingent. Debates that feel decisive in one period can later look narrow or unproductive because the underlying frameworks—what counts as evidence, what questions seem worth asking, what concepts are available—shift over time. The second clause sharpens the claim: knowledge is not merely cumulative “answers,” but a force that reshapes inquiry itself. As methods, data, and theories change, they alter both our aims (what we seek) and our perceptions (what we find). The quote thus cautions against treating contemporary controversies as timeless, and it encourages humility about the durability of today’s certainties.