The subject of the verb "make" in this sentence

Question

I encountered a sentence in The New York Times:

This is an engrossing story, which Wood tells with a mastery of detail and a modern plainness of expression that makes a refreshing contrast with the 18th-century locutions of his subjects.

Isn't the subject of the verb "make" a mastery of detail and a modern plainness of expression? Shouldn't the verb "make" take the third-person plural conjugation and thus be "make" instead of "makes"? Had I read it elsewhere, I'd be certain it was a mistake, but it's The NYT and it's Richard Brookhiser.

Also the title of the article In ‘Friends Divided,’ John Adams and Thomas Jefferson Beg to Differ reads strange. I thought one person could beg to differ with someone else. I understand the author tries to say Adams and Jefferson beg to differ with each other, but is this usage, where the subject of beg to differ is multiple parties, common and natural?

Google search results of we beg to differ and they beg to differ all appear to point to an implied "with you" or "with the mainstream opinion" or "with the said opinion," instead of "with each other" as is used in the article title in question. Are there instances where "beg to differ" is used to mean "we disagree with each other"?

Answer 1

As you point out, it's odd that there is a compound subject but the verb is conjugated in the singular. Either it's a grammatical error, or, more likely, the author intends the subject to be only the second part of the compound, "a modern plainness of expression."

The key word is "contrasts" -- we have to select which part of the sentence is a reasonable contrast with "the 18th-century locutions of his subjects". The first part of the compound, "a mastery of detail", doesn't really contrast with "locutions", so again it's likely the subject is only the second part.

Simplifying to highlight the subject-verb relationship:

It is an engrossing story, and Wood's plain narrative makes a refreshing contrast with the verbosity of his characters.

The original phrasing is unnecessarily confusing. Better might be:

This is an engrossing story that Wood tells with a mastery of detail, and his modern plainness of expression makes a refreshing contrast with the 18th-century locutions of his subjects.

Authors often take liberties with their titles. In this case it's unclear whether John Adams and Thomas Jefferson Beg to Differ means they both have agreed to disagree with someone else, or they disagree with each other, but either way you should be able to figure out which by reading the blurb.

Assuming that they disagree with each other, then the title is a cute poetic license that evokes the image of Jefferson and Adams, standing in an 18th-century Colonial meeting hall, politely arguing.