may borrow from any part of speech, or from any
expression._]

19. Owing to the scarcity of distinctive forms, and to the
consequent flexibility of English speech, words which are usually
other parts of speech are often used as nouns; and various word groups
may take the place of nouns by being used as nouns.

[Sidenote: _Adjectives, Conjunctions, Adverbs._]

(1) _Other parts of speech_ used as nouns:--

_The great_, _the wealthy_, fear thy blow.--BURNS.

Every _why_ hath a _wherefore_.--SHAKESPEARE.

When I was young? Ah, woeful _When_!
Ah! for the change 'twixt _Now_ and _Then_!
--COLERIDGE.

(2) _Certain word groups_ used like single nouns:--

_Too swift_ arrives as tardy as _too slow_.--SHAKESPEARE.

Then comes the "_Why, sir_!" and the "_What then, sir_?" and the
"_No, sir_!" and the "_You don't see your way through the
question, sir_!"--MACAULAY

(3) Any part of speech may be considered merely as a word, without
reference to its function in the sentence; also titles of books are
treated as simple nouns.

The _it_, at the beginning, is ambiguous, whether it mean the sun
or the cold.--Dr BLAIR

In this definition, is the word "_just_," or "_legal_," finally
to stand?--RUSKIN.

There was also a book of Defoe's called an "_Essay on Projects_,"
and another of Dr. Mather's called "_Essays to do Good_."--B.
FRANKLIN.

[Sidenote: _Caution._]

20. It is to be remembered, however, that the above cases are
shiftings of the _use_, of words rather than of their _meaning_. We
seldom find instances of complete conversion of one part of speech
into another.

When, in a sentence above, the terms _the great_, _the wealthy_, are
used, they are not names only: we have in mind the idea of persons and
the quality of being _great_ or _wealthy_. The words are used in the
sentence where nouns are used, but have an adjectival meaning.

In the other sentences, _why_ and _wherefore_, _When_, _Now_, and
_Then_, are spoken of as if pure nouns; but still the reader considers
this not a natural application of them as name words, but as a figure
of speech.

NOTE.--These remarks do not apply, of course, to such words as become
pure nouns by use. There are many of these. The adjective _good_ has
no claim on the noun _goods_; so, too, in speaking of the _principal_
of a school, or a state _secret_, or a faithful _domestic_, or a
_criminal_, et