The second clause is clearly explanatory of the first; and the third clause simply modifies the second by showing the degree of untruthfulness of the man.
With the new meaning of the colon we are now considering, a colon after “candid” informs the reader of the relation between the main groups of the sentence:
27-1. He was not candid: he did not shun concealments and evasions; but positive lies he had kept from.
So far as the mere grouping is concerned, this could be done in Nos. 26 and 27 by a semicolon and a comma in each; but the semicolon would not inform the reader of the true relation between the two larger groups. The colon would still be required if the next two groups took a comma, or even no mark, between them.
We called this relation that of apposition. We might say, somewhat more specifically, that the second group is an amplification in language to express an extension of the idea, or to fortify the image, of the first group. This purpose may also be accomplished by a contrast between the ideas expressed in the two groups.
The writer on punctuation who says, as do many such writers, that the colon is an obsolete mark, except in its formal use for enumeration, does so, we believe, in ignorance of the useful and beautiful purpose it performs in a very large class of sentences.
1. There is purpose in pain; otherwise it were devilish.
2. But not thieves; nor robbers; nor mobs; nor rioters, insurgents, or rebels.
3. The people’s voice is odd; it is, and it is not, the voice of God.
4. He cared little for poetry; fact, and not fancy, satisfied him.
5. The second Folio, reprinted from the first, was published in 1632; the third Folio, in 1664; and the fourth, in 1685.
6. Wealth has greatly accumulated; machinery has come to do a large part of our work; and all sorts of people have more or less leisure on their hands.
7. Render therefore to all their dues: tribute to whom tribute is due; custom to whom custom; fear to whom fear; honor to whom honor.
8. The evils are very real, grave, and widespread; whether a trifle more or less so than these rough estimates make out, is of small account.
9. His condition was not toxic; for he had never been a worker in paints, minerals, or other poisonous substances, and he did not use alcohol or tobacco.