In the following degrees — "Bachelor of Science" and "Master of Science" — "science" is an uncountable or singular noun.
In contrast, in "Bachelor of Arts" and Master of Arts, "arts" is countable and plural. Wikipedia says the Master of Arts "degree is usually contrasted with the Master of Science." If so, then they should probably use the same grammar, no?
From Cambridge dictionary,
arts C1 [ plural ]: subjects, such as history, languages, and literature, that are not scientific subjects
There are several different majors/fields under each degree. We can have "Master of Science in Physics, Chemistry, Psychology, etc." and "Master of Arts in Linguistics, Political Science, Economics, etc." The point I am trying to make is that since the degrees are similar in the sense that they have multiple fields, shouldn't they both have the same noun form in the titles? Like, either both should have the countable or plural "arts" and "sciences", or both should have the uncountable "art" and "science".
There are departments/schools/programs with "sciences" in their name though: Natural Sciences, Earth Sciences, etc.
Why do they not have the same noun form in the degree titles? Why is it not "Master of Sciences"?
Best Answer
Overview
The central issue of question is the countable and uncountable usages of the words science and art.
Explanation
Following are two common usages of science:
We might think about applying the same pattern as above to the word art. Between usages of the two words, science and art, we find great similarity, but also a few differences.
Art is an activity, but it is one that produces objects.
Any of the following are common ways to refer to objects produced by artistic activity (such as drawings, paintings, or sculptures):
Not all kinds of artistic activity produce artwork.
In some cases, we find that the word art confuses the activity with the objects.
As an example, the following two simple statements are not parallel:
We need a way to refer to the activity of art, as distinct from artwork. The arts are all activity that we think of as artistic.
As the arts is a countable usage, we also have the singular form. An art is any field within the arts, or sometimes, any field within only the visual arts.
Putting together the above, following are common usages of art:
Since science is all activity that we think of as scientific, we have no strong reason to use the term the sciences. Yet, sometimes we want to emphasize the diversity and number of different fields, or to create a feeling that is general but also grand.
The sciences has the same meaning as science, but has a specific feeling that makes it uncommon except in certain literary contexts.
We can conclude with the following:
Examples
For degrees, like a Bachelor's degree, we emphasize the activities, science and the arts. We call the degrees Bachelor of Science and Bachelor of Arts. In titles, we often omit articles, otherwise we would use Master of the Arts. Master of Sciences would feel too general, as though someone had studied every field of science for a long time.
This patterns appears elsewhere.
Following are two examples, both related to the US government:
The National Science Foundation and the National Endowment for the Arts are both agencies of the government. (The NSF might have been called the National Foundation for the Sciences, but this name may seem to emphasize the fields and their differences, rather than all of science together as a valuable pursuit.)
The Constitution lists the powers of Congress.
It describes one of the powers in the following text (Article I, Section 8, Clause 8):
(Note that capitalization rules are different today than during the earlier period, which treated important common nouns the same as names and other proper nouns.)
The text means that Congress has the power to pass laws related to intellectual property ("securing", "exclusive right"), specifically for copyright ("the arts", "authors", "writings") and for patents ("science", "inventors", "discoveries").