55-2. In conclusion: the jury seemed unable to comprehend either the evidence or the charge of the judge; the judge was not entirely free from prejudice; and the prisoner was unable to obtain important evidence.
Here “in conclusion” seems to bear no grammatical relation to what follows. It is, however, the remnant of a clause which bears the colon relation to what follows; and therefore the colon is used after it. Such a clause might read thus, “I will state, in conclusion, the facts in the case.”
YES, NO, AGAIN, ETC.
The words yes, no, again, to sum up, to proceed, etc., are often used in this way, and so require the colon:
56. Do you think he will meet the expectations of his friends? Yes: he has never failed to meet reasonable expectations.
Apparently in the absence of a comprehension of the colon relation between “yes” or “no” and what follows, even careful punctuators seem to prefer the semicolon after these words; and, it may be said, convention thus overrides reason, making the semicolon far more common than the colon for this punctuation.
The conventional punctuation of the sentence is as follows:
56-1. Do you think he will meet the expectations of his friends? Yes; he has never failed to meet reasonable expectations.
As marks are used mainly to assist the reader in so grouping words that their relations may be readily seen, it is apparent that a mark is not needed when the grouping is unmistakable in its absence. There is a large class of groups so formed and so connected that a mark of punctuation between them is superfluous, although used quite in accordance with our general principle, as exemplified in Sentences 1 and 1-1. The following sentence exhibits such grouping: