Key words here are "despite" (indicating that we're looking for a shift in meaning) and "veracity" (truthfulness). "Spurious" (false) and "aver" (to assert) best complete the sentence.

The first key word here is "propriety" (respectability, uprightness). The second blank is set up to contrast with "propriety." "Debauchery" (drunkenness, corruptness) fits. Knowing that, we can assume that his brother expresses the opposite of this; he is "abstemious" (self-disciplined, sober).

Since there is a sentence shift, we are looking for two words that are dissimilar in meaning. “Analogous” describes something that is similar or comparable to something else in a particular way. “Singular” has several definitions. “Singular” can mean exceptional, or it can mean bizarre. In this case, it means one-of-a-kind. “Singular . . . analogous” is the correct answer.

In regard to the first blank, "expansive" (extensive in size or topic) and "comprehensive" (complete) are very similar words. However, the sentence notes that the collection "covers thousands of years of art history," which speaks of breadth, not complete depth. Thus, "expansive" is a more exact term and the correct answer.

In regard to the second blank, the second clause of the sentence speaks of it taking a long time to do something to the collection. "Capitalize" (exploit) does not work well by its definition, while "scrutinize" (examine carefully) would, indeed, be something that would take several days to do in a large collection. Thus, the correct answer is "expansive . . . scrutinize."

The easier blank to choose is the second one, for it indicates a kind of intensification from the adjectival phrase "attentive to details." The best option here is "fastidious," which means very attentive to details—an appropriate option! When a professor is so attentive to detail, it is likely that he will be called a "pedant," which describes just such an academic person.

This sentence clearly makes a parallel between "succinct" and the second blank. The idea is that Frederick's statements appear to be short. That is, they appear to be rather brief. Hence, they have the appearance of "brevity"—meaning briefness. The word "pithy" can describe a dense part of fruit (the "pith"), but it can also mean short and expressive, describing language that pierces to its meaning directly. This seems to be an excellent description for Frederick's remarks—at least for how they appear.

In the second clause of this sentence, it is hinted that Harvey has a bold position (i.e. bold and/or strong beliefs). It seems that he needs to change this fact, though we are not told that he should completely deny his beliefs. The word “alter” might work well for the first blank, but “attenuate” is an even better option, for it means to reduce in force—something that describes just what Harvey needs to do to his bold theories.

We tend to think of dogmas and being “dogmatic” in terms of religious beliefs. In general, the term “dogmatic” describes a set of beliefs that are established on the strength of an authority. This describes the obedience paid to Aristotle described in the first half of this sentence. The critics, however, also did not alter their own positions much. Hence, “beliefs” is a good option for the second blank.

We are not told much about John’s actions toward his students, other than the fact that he is staring at them. The implication is that he is staring very strongly at them—he is “not merely [staring].” The word “glower” means to scowl—a very strong sort of look.  When someone "prattles," he or she talks at length foolishly or about things that are not important. This functions well for describing the students' actions, which so vexed John.

The main clue in this sentence is the expression, "which could almost cause deafness." This implies that Byron's speaking style was very loud. It is most likely that it had this effect on those who were sitting at the locations closest to him. The "proximity" is the close space around someone. Words related to "proximity" are "approximate" and "proxy." "Stentorian" describes a style of speaking that is very loud. This best fits the clues mentioned above.