'ambiguous' description; a phrase of the form 'the so-and-so' (in the
singular) I shall call a 'definite' description. Thus 'a man' is an
ambiguous description, and 'the man with the iron mask' is a definite
description. There are various problems connected with ambiguous
descriptions, but I pass them by, since they do not directly concern
the matter we are discussing, which is the nature of our knowledge
concerning objects in cases where we know that there is an object
answering to a definite description, though we are not acquainted with
any such object. This is a matter which is concerned exclusively with
definite descriptions. I shall therefore, in the sequel, speak simply of
'descriptions' when I mean 'definite descriptions'. Thus a description
will mean any phrase of the form 'the so-and-so' in the singular.

We shall say that an object is 'known by description' when we know that
it is 'the so-and-so', i.e. when we know that there is one object, and
no more, having a certain property; and it will generally be implied
that we do not have knowledge of the same object by acquaintance. We
know that the man with the iron mask existed, and many propositions
are known about him; but we do not know who he was. We know that the
candidate who gets the most votes will be elected, and in this case we
are very likely also acquainted (in the only sense in which one can
be acquainted with some one else) with the man who is, in fact, the
candidate who will get most votes; but we do not know which of the
candidates he is, i.e. we do not know any proposition of the form 'A is
the candidate who will get most votes' where A is one of the candidates
by name. We shall say that we have 'merely descriptive knowledge' of the
so-and-so when, although we know that the so-and-so exists, and although
we may possibly be acquainted with the object which is, in fact, the
so-and-so, yet we do not know any proposition '_a_ is the so-and-so',
where _a_ is something with which we are acquainted.

When we say 'the so-and-so exists', we mean that there is just one
object which is the so-and-so. The proposition '_a_ is the so-and-so'
means that _a_ has the property so-and-so, and nothing else has. 'Mr.
A. is the Unionist candidate for this constituency' means 'Mr. A. is
a Unionist candidate for this constituency, and no one else is'. 'The
Unionist candidate for this constituency exists' means 'some one is a
Unionist candidate for this constituency, and