ndow is not to the left of the door. But we can form no image
of the fact that the window is not to the left of the door. Attempts
have often been made to deny such negative facts, but, for reasons which
I have given elsewhere,* I believe these attempts to be mistaken, and I
shall assume that there are negative facts.

* "Monist," January, 1919, p. 42 ff.

Word-propositions, like image-propositions, are always positive facts.
The fact that Socrates precedes Plato is symbolized in English by the
fact that the word "precedes" occurs between the words "Socrates" and
"Plato." But we cannot symbolize the fact that Plato does not precede
Socrates by not putting the word "precedes" between "Plato" and
"Socrates." A negative fact is not sensible, and language, being
intended for communication, has to be sensible. Therefore we symbolize
the fact that Plato does not precede Socrates by putting the words "does
not precede" between "Plato" and "Socrates." We thus obtain a series of
words which is just as positive a fact as the series "Socrates precedes
Plato." The propositions asserting negative facts are themselves
positive facts; they are merely different positive facts from those
asserting positive facts.

We have thus, as regards the opposition of positive and negative, three
different sorts of duality, according as we are dealing with facts,
image-propositions, or word-propositions. We have, namely:

(1) Positive and negative facts;

(2) Image-propositions, which may be believed or disbelieved, but do
not allow any duality of content corresponding to positive and negative
facts;

(3) Word-propositions, which are always positive facts, but are of two
kinds: one verified by a positive objective, the other by a negative
objective.

Owing to these complications, the simplest type of correspondence is
impossible when either negative facts or negative propositions are
involved.

Even when we confine ourselves to relations between two terms which are
both imaged, it may be impossible to form an image-proposition in which
the relation of the terms is represented by the same relation of the
images. Suppose we say "Caesar was 2,000 years before Foch," we express
a certain temporal relation between Caesar and Foch; but we cannot allow
2,000 years to elapse between our image of Caesar and our image of Foch.
This is perhaps not a fair example, since "2,000 years before" is not a
direct relation. But take a case where the rel