Time was when I was much interested in the philosophers of the Frankfurter Schule. That was in the 'seventies and 'eighties. Less interested now, I am still intrigued by Adorno's critique of Heidegger. Is it worth anything? For that matter, are Heidegger's ideas worth anything? Let's see.
I will explain one aspect of Heidegger's notorious Seinsfrage, an aspect centering on the role of the copula in predicative sentences/judgments. True-blue Heideggerians may not recognize much of their Master here, but I'm a thinker not an exegete. I will also consider what Adorno has to say in criticism of Heidegger in the section on the copula in Negative Dialektik.
1. Consider a simple predicative sentence such as 'The sky is blue,' or simpler still, 'Al is fat.' The sense of the sentence is built up from the senses of its constituent terms: 'Al' and 'fat' clearly play a role, but what about 'is'? Does it play a semantic, as opposed to a merely syntactic, role? Is 'is' perhaps redundant? 'Al' refers to something, and perhaps 'fat' does as well; does 'is' refer to anything?
Instead of writing 'a is F' one could write 'Fa' as one does in the artificial language of standard symbolic logic. And there are natural languages in which there either is no copula sign or in which the copula sign can be omitted. In Turkish, for example, one can say Deniz mavi thereby expressing what we express in English by 'The sea is blue' but cannot express (in standard adult English) by 'The sea blue.' But of course Turkish does have a copula sign. Since Turkish is an agglutinative language and makes heavy use of suffixes, the copula is appended to the adjective mavi as a suffix thereto. Thus, Deniz mavidir. 'Dir' in this example is the copula sign despite its being a suffix. And in the case of substandard English — 'He one bad dude,' 'Coffee hot' — the copula sign is tacit or implied. There are also cases in which copulation is expressed by a word that grammatically cannot be a copula: 'He be stoned.'
In the case of 'Fa,' the natural thing to say is that the sign for the copula is the immediate juxtaposition of 'F' and 'a' in that order. So there is a copula in 'Fa,' though there is no separate sign for it. The copula is the ordered juxtaposition. I conclude that the word 'is' is redundant, but that what it expresses, the copulation, is not. Copulation can be expressed in different ways, or even left unexpressed but implied; what is impossible is that there be no copulation. For without it there are no complete thoughts and no declarative sentences.
It follows that the problem of copulative being cannot be dismissed by saying that there are natural or artifical languages in which there is no sign for the copula, whether a separate sign or a suffix. There must at least be a copulative tie at the level of Fregean sense. There is more to the complete thought, the Fregean Gedanke, that Al is fat than the sense of 'Al' and the sense of 'fat.'
2. But it doesn't follow from the necessity of copulation at the level of Fregean thoughts or propositions that there is a problem of copulative being: copulation might be purely logical or semantical rather than ontological. In Fregean terms, there might not be anything at the level of reference (Bedeutung) to which the copulative 'is' refers.
In 'Al is fat,' 'Al' refers to Al, all 250 lbs of him, and 'fat' refers to the property of being fat. Does 'is' have a referent as well? Are there three things in the world: Al, fatness, and the copulative link? This leads to trouble very quickly. If the copulative link is a tertium quid, a third thing, then what will link it to Al and fatness? After all, the fact of Al's being fat is not a mere sum of Al + copulative link + fatness, any more that the true sentence 'Al is fat' is a mere list of 'Al,' 'is,' and 'fat.' If the copulative link is a tertium quid, then we are embarked upon Bradley's regress.
The copula 'is' is not a stand-alone expression like 'Al.' Traditionally, this is expressed by saying that 'is' is not categorematical but syncategorematical: its meaning is a co-meaning, a meaning together with, and only together with, the expressions flanking it. No doubt the copula 'is' has a meaning; but it would be a mistake to hypostatize or reify its referent, to make of it a separate entity.
3. That Heidegger is guilty of a hypostatization and ontologization of the copula is essentially Adorno's charge:
In every predicative judgment, 'is' has its meaning, as have the subject and the predicate. But the state of affairs is a matter of intentionality, not of being. The copula is fulfilled only in the relation between subject and predicate. It is not independent. Heidegger, in misplacing it beyond the sole source of its meaning, succumbs to that reified thought to which he took exception. (Negative Dialectics, p. 101. I have slightly emended Ashton's translation.)
Adorno's main point is that the copulative 'is' is syncategorematic or synsemantic. It does not have meaning independently or on its own in the way a proper name does. It welds subject and predicate together into a state of affairs (Sachverhalt) that subsists merely on the intentional plane, as an object of thought, or content of judgment, but not in reality. Thus there is nothing in reality corresponding to the copulative 'is.' 'Is' lacks a Fregean referent. There is no Being (Sein) to which 'is' refers. Heidegger's talk of Being (das Sein) as different from beings (das Seiende) is due to illicit reification or hypostatization. Not only is this reification illicit, it contradicts Heidegger's constant insistence that Being is not itself a being. Adorno speaks of Heidegger's extrapolation from the copula to Being and considers this to rest on a confusion of the general meaning of the copula 'is' with the specific meaning it acquires in particular judgments.
The copulative 'is,' Adorno claims, is like an "occasional expression." In contemporary Anglo-analytic terms, it is like an indexical such as 'I,' 'here,' or 'now.' The first-person singular pronoun has a general meaning: 'I' said by me has the same general meaning — the same Kaplanian character — as 'I' said by you. But when I say 'I' I refer to me, while when you say 'I' you refer to you. From the fact that 'I' has a general meaning, it does not follow that every use of 'I' has the same referent. Similarly, from the fact that the copulative 'is' has the same general meaning in each predication, it does not follow that the 'is' in each predication refers to one and the same entity, Being. There is no Being in distinction from beings, any more than there is a Universal Ego distinct from particular egos.
4. Can Heidegger be defended against Adorno's charge that his Being is nothing but a reification (Verdinglichung) of the copula? Well, Heidegger himself insists that Being is not a being. Being is neither a being nor a property of beings. Nor is Being a concept. If it were, it would be the emptiest of empty abstractions. Being is a Third that mediates between concepts and beings, but is not itself something mediated. It resembles a metaphysical Absolute as Adorno suggests. So Heidegger would plead innocent to the charge of reification. For Adorno to make the accusation stick, he has to prove that there is no Third possible between concepts and beings. If he simply assumes this, he begs the question against Heidegger. Similarly, if he simply assumes that everything is mediated, that there is nothing that is not a member of the all encompassing system of intermediating entities, then he begs the question against Heidegger. For Heidegger's whole project is to think Being in its difference from beings. This implies that Being is transcendent of beings.
5. My own view is that there is plenty to criticize in both Heidegger and Adorno. But on the topic of the copula, something like Heidegger's position is defensible. Let me try to argue this out.
It is quite clear that 'is' in 'The sky is blue' does not designate some separate individual being, whether it be a predication relation or anything else. Still, the copula plays a role and does a job: it expresses the linkage of subject and predicate. After all, Al is fat. And even if he is not in reality fat, he can be (falsely) thought to be fat, and the propositional content of that thought, his being fat, is not the mere sum of the sense of 'Al' and the sense of 'fat.' So the linkage is not nothing. It is what transforms items not capable of having a truth-value into a structure that is capable of having a truth-value. Neither Al, nor the sense of 'Al,' has a truth-value. But 'Al is fat' has a truth-value. So the copulative 'is' plays a crucial role even though it lacks a specific referent. The problem is to understand that role.
We seem to face an aporia. On the one hand, the copulative link, or predicative tie, is not an entity in addition to Al and fatness, on pain of Bradley's regress. (Adorno does not mention Bradley's regress, but it could be taken as a manifestation of the illicit reification which Adorno does allege.) On the other hand, the link is not nothing. If it is not something and not nothing, then we have a contradiction.
Should we just accept this contradiction? Let us explore the contradiction of copulative being a bit further. Suppose 'Al is fat' is true. Then the state of affairs, Al's being fat, obtains. But analysis reveals only an individual and a property, but no being. Yet without the copulative link there would be no state of affairs at all. On the one hand the state of affairs is just its two constituents; on the other is it more than its two constituents.
As far as I can see, Adorno offers us no solution to this contradiction at all. He speak of a general meaning of 'is' common to all predicative states of affairs. But this cannot be what binds together the constituents of any particular state of affairs. Adorno glides right past the problem and leaves us with the contradiction.
One way to avoid the contradiction is by saying that the copulative link is made by the mind: the linking of subject and predicate representations in a judgment derives from mental synthesis. In Kantian terms, the representations are combined in the unity of one consciousness. A judgment is a unity of constituents, not a mere sum of constituents. But the ground of this unity cannot be located within the judgment as a further constituent. Otherwise we get Bradley's regress. One solution is to locate the unifier outside the judgment as the synthesizing mind whose combinative activity creates a sense-structure capable of being true or false.
Now suppose the judgment is true. If it is true that Al is fat, then fat Al exists, and indeed exists outside the mind of the judger. In that case, pace Adorno, the state of affairs is not merely a matter of intentionality; it is also a matter of being. But the existence of fat Al cannot depend on the subjective synthesizing of an empirical judger. It is an objective fact, true of all actual and possible judgers. In Kantian terms, the 'is' therefore points back to the transcendental or objective unity of apperception. Now if we think of Heidegger's Sein in analogy to Kant's transcendental (objective) unity of apperception, then we can see how it escapes Adorno's charge of hypostatization.
Being is not a being, but a transcendental condition of the manifestation of beings; it is also not a concept or category, but the vehicle of all concepts. As such it is a Third that mediates between subject and object, but is not itself mediated by anything. And of course this is why the neo-Hegelian Adorno objects it it. For him, nothing escapes mediation, Vermittlung, as we may see in future installments.
Although there is plenty of need for further explanation, what I have said suffices to show that Adorno's charge that Heidegger hypostatizes the copula fails. Heidegger is on to a genuine problem the solution to which is by no means obvious.