Invisible Man by Ellison

to wither or weaken — especially from lack of use

contented (unworried and satisfied) — often to a fault

to disagree; or disagreement or conflict — typically between people who cooperate, and often with official or majority beliefs

the condition of variety — especially in reference to members of a population group who are of different races or cultures

not correct

giving careful attention to detail

or:

excessively concerned with cleanliness or matters of taste

taking pains to avoid being observed

or:

in a manner indicating nervousness (being cautious or appearing suspicious)

studies intended to provide general knowledge and intellectual skills (rather than occupational or professional skills)

of a person:  capable of thinking clearly

or:

of language:  clearly expressed so it is easily understood

for one to say they no longer believe a previously made statement or belief — often while under pressure

submissive — typically excessively so (so submissive or eager to serve and please that one seems to have no self-respect)

or:

relating to the work that requires obeying demeaning commands

or:

slave-like or relating to slaves