Proposition, Judgment and Fact

In one line

A judgment is the mental act of asserting; a proposition is what is asserted; a fact is what makes it true.

In the wording a student can write in an examination: judgment is a mental act performed by a person at a time, and it is studied by psychology as well as by logic. A proposition is the content of that act, and it is what bears truth and falsity. A fact is a state of affairs in the world, and it is what a true proposition corresponds to.

The three lined up

It is worth seeing the three as three positions on one line.

The judgment stands at the mental end. When a judge, reading the evidence, concludes that the notice was served, an act takes place in a mind at a moment. That act is a judgment.

The proposition stands in the middle. It is what the judgment asserts: that the notice was served. It has no date and no owner, and it is the same proposition whoever judges it and whether or not anybody does.

The fact stands at the world end. Either the notice was served or it was not. That is a state of affairs, not a claim about one, and it exists whether or not anybody knows about it.

The relations between them are exact. A judgment asserts a proposition. A proposition is made true by a fact. Neither relation runs the other way: a proposition does not assert a judgment, and a fact does not make a judgment true.

Proposition against judgment

This is the same distinction, transposed, as the one between implication and inference at sequence 120. Inference is the act, implication is the relation; judgment is the act, proposition is the content.

Three consequences, each of them examinable.

A judgment happens; a proposition does not. It makes sense to ask when a judgment was made and by whom. It makes no sense to ask when a proposition was made, though it makes sense to ask when it was first expressed, which is a different question about a sentence.

A proposition exists unjudged. "There were 4,312 blades of grass in this field on 1 January 1800" is a proposition, it is true or false, and nobody has ever judged it. If propositions were judgments, unjudged propositions would be impossible.

The same judgment can be made by two people; the same proposition can be the content of two judgments. Two judges reaching the same conclusion perform two acts with one content.

Where the confusion does harm. Students who identify the two end up saying that a proposition is true because somebody believes it, which is the correspondence theory abandoned in a single step, and is why chapter 130 insisted that truth is not belief.