The meanings that lie in this unlikely 'is', and are already referred to in it in an unlikely and self-evident way, are thus accumulating. And yet we have so far overlooked one further and quite central meaning. It comes to light if the statement 'The board is black' is emphasized and spoken accordingly: 'The board is black'. We are now referring not only to being such and such, nor only to the being at hand of whatever is such and such. Rather we are also referring to the fact that what I am saying here and expressing in this statement is true. The board is truly black. The 'is' thus also means the being true of whatever is said in the statement. If we leave aside the more extreme and superficial forms of the 'is' and concentrate on those which spring from its inner content-matter, we may now say that what is referred to in the 'is' is what-being, whether in the form of being such and such and of essential being, or of that-being and being true.
The last-named meaning of the 'is' also became a point of departure for various theories, particularly prevalent today, concerning the copula, the λόγος, and judgement in general. It has been said that something is affirmed in such statements, the board's being black is affirmed, and so the 'is' properly expresses this affirmation. What is affirmed in this affirming is the fact that whatever is spoken of is valid, so that the 'is' also comes to be interpreted as validity and being valid The theory of judgement has been developed in this direction by Lotze, and subsequently by Windelband, Rickert, and Lask. Especially in the case of Rickert, this interpretation of the judgement as expressing a validity became an approach for developing a value-philosophy. Rickert said: If a validity is affirmed in the judgement, then this is only possible if validity has a standard; everything valid must be measured by what ought to be. An 'ought' can only be in force and binding as 'ought' if it is grounded upon a value. The orientation toward value-philosophy thus arises in this way.
None of the theories that have arisen concerning the 'is' and being in the proposition are correct, because they are one-sided. Yet why are they onesided? Because they fail to see and to take account of the multiplicity of meanings pertaining to the 'is'. Will we therefore attain a true theory by assembling all the interpretations that have emerged and by achieving a compromise? Things are not so simple. What is at stake is to see something far more essential. It is not a matter of seeing that all these meanings—what-being, that-being, and being true-are to be found and may be found in the 'is', but rather the fact that they all must be found in it and why they must be found in it, at first and for the most part in an unarticulated and undifferentiated way. It is a matter of comprehending this peculiar undifferentiatedness and universality of the 'is' as the originary and primary essence of the copula or of what is superficially designated the copula. It is by no means the case, therefore, that the 'is' at first merely means copulatio (the linking of words) and that the other meanings then accrue to it one after the other, rather the converse is the case: