A “LONG” SUBJECT
When a subject is composed of two or more words, and these words do not readily group themselves, a comma may be helpful to group them as a subject. This failure of words to fall readily into a group is generally due to one of three causes: the subject may be somewhat long and contain marks of punctuation, or it may end with a word that seems itself to sustain grammatical and sense relation with the word or words following it, or it may end with a verb. In either of such cases the comma serves to show the end of the subject; and its use is therefore helpful punctuation:
78. Whatever is, is right.
79. He that sees a building as a common spectator, contents himself with speaking of it in the most general terms.
The use of the comma after “spectator” simply warns the reader that “the spectator contents himself” is not the meaning of the language at this point. The comma disconnects “spectator” and “contents,” just as the comma disconnects certain words in Sentence 1-1. Thus the punctuation of this sentence depends upon the fundamental principle of grouping and disjunction.
This principle also explains the value of a comma at the end of several subject-nouns not connected by a conjunction:
80. Ease, indulgence, luxury, sloth, are the sources of misery.
With the conjunction “and” before “sloth,” the comma after “sloth” would not be needed, as “and” and the comma before it would give notice of the ending of the group.
The value of a comma in No. 79 is unmistakable; but is such punctuation helpful when the subject clearly ends itself, either because of its manifest completeness or because there is no apparent relation between the last word of the subject and the predicate verb? Probably a definite and satisfactory answer to this question cannot be given, for the mental capacity and alertness of the reader are involved.