But Lotze’s interpretation of Plato is not our theme, any more than criticizing that interpretation is our current project. What we are aiming at in our demonstration is something else: an understanding of the genesis of the concept of validity and of the doctrine of the ideal being of truth. By that I mean the question: What do we establish about truth when we say that the being of propositions is validity, and that validity is the form of actuality that Plato ascribed to the ideas, namely, ideal being? In answering that question we will come to learn something about the [73] roots (and about a major root) of the critique of psychologism. We get some insight into the basic orientation of the concept of validity by asking the question, “What is truth?”
In the first place, with regard to what we said earlier about the critique of psychologism, we can now see from Lotze’s interpretation of the doctrine of ideas how Husserl really landed in that error of his that we noted above. Lotze says: Truth, as a true proposition, is valid; but validity is the form of actuality pertaining to ideas; and the idea also has the property of being universal in contrast to the sensible particulars. So in keeping with that, propositions—valid ones—are ideas; they are likewise the ideal in the sense of the universal for the particulars in the propositions—the “positions.” So if we reduce Husserl’s error to a syllogism, it consists simply in the fact that he proceeded as follows:
The major: Idea = validity = proposition.
The minor: Idea = universal = form = genus.
Conclusion: Proposition = universal, identical with idea, and thus:
Proposition = genus to the posited judgments.54
But we now disregard Husserl’s error and instead ask: When we characterize truth as validity, do we in fact gain anything toward clarifying the essence of truth? Let us not forget: Lotze makes the claim for validity that it is the form of the actuality of the true proposition. And we must keep firmly in mind how Lotze proceeds, to the point where he derives the four different forms of actuality.
Recall what he says at that point:
We call a thing “actual” when it is, in contrast to another that is not; we call an event “actual” if it occurs, in contrast to another that does not occur; we call a relation “actual” if it obtains, as opposed to one that does not ob-tain; and lastly we call a proposition “actually true” if it is valid. (p. 511)
54. [“Posited judgments”: the German is Setzungen (also in Moser, p. 154.14), which does not have the meaning of Position as affirmedness, that Heidegger discussed above. Here it refers to acts of judgment.]