Ngram shows how often words and phrase are used in English books over time. "Diversity" has been rising steadily since 1960:But different kinds rose at different times. First was "ecological diversity", plausibly from environmentalism:Next was "ethnic diversity", plausibly combining racial and environmental concerns:Soon after "multicultural" "cultural diversity", via analogy to "biological diversity":More recently rose "gender diversity":Over this period, calls to attend to "ideological diversity" rose and fell several times:I find no results re "diversity" tied to "morals" or "ethics", but see "moral pluralism":which tracks ideological diversity pretty well.
First was "ecological diversity", plausibly from environmentalism:Next was "ethnic diversity", plausibly combining racial and environmental concerns:Soon after "multicultural" "cultural diversity", via analogy to "biological diversity":More recently rose "gender diversity":Over this period, calls to attend to "ideological diversity" rose and fell several times:I find no results re "diversity" tied to "morals" or "ethics", but see "moral pluralism":which tracks ideological diversity pretty well.