70 < CHAPTER TWO
But errancy, how being has misleadingly come to show up (to seem to show up), is a topic in itself and touches on one of the most complex in Heidegger, his account of truth. In IM, he puts it this way. “The space, so to speak, that opens itself up in the interlocking of Being, unconcealment, and seeming, I understand as errancy [Irre]. Seeming, deception, delusion, errancy stand in definite relations as regards their essences and their ways of happening, relations that have long been misinterpreted for us by psychology and epistemology, relations that we therefore in our everyday Dasein barely still experience and barely recognize with adequate perspicacity as powers” (IM, 115 {120}). But what could it mean to say that this is not a matter of epistemology? How could a disclosive moment of unconcealment seem to be what it is not? Does it mean that the assertion, “beings are substances perduring through time,” merely what lies before us at hand, is false? But Heidegger tells us that ontological truth is ἀλήθεια, that unconcealment, uncovering what is hidden, and while he does not reject truth as correctness, correspondence, he insists it is not the mode of truth appropriate ontologically. How does errancy fit in with that view?
We need to recall first that Heidegger’s claim that ontological truth is unconcealment, ἀλήθεια, is meant to contrast with what he has identified as by far the greatest “errancy” in the Western philosophical tradition: the priority of logos as ratio in the understanding of the meaning of Being. By λόγος he means most generally a theory of pure thinking, all possible thinking with any object other than thought itself, the results of which are taken to determine, ground the possibility of, what could be (from Plato’s Ideas to Kant’s categories). As we have seen, this ultimately means that being must be understood as what could be the content of an assertion. The meaning of Being is then understood to be intelligibility or knowability, and the corresponding notion of truth is what Heidegger calls “correctness,” correspondence with the beings about which assertoric claims are made. This will, he thinks, inevitably lead to the construal of being as mere presence at hand. By contrast, Heidegger insists that such a notion of truth cannot be fundamental because it clearly relies on a prior disclosure, an unconcealment that an assertion depends on and points to. This original “uncovering” must count as primordial truth. So, about the conventional view, Heidegger asks: “However, we would still like to raise one question. What does ‘logic’ mean? The term is an abbreviation for ἐπιστήμη λογική, the science of logos. And logos here means assertion. But logic is supposed to be the doctrine of thinking. Why is logic the science of assertion? Why is thinking determined on the basis of assertion? This is by no means self-evident” (IM 127 {132}). But there is an obvious answer to Heidegger’s question. The assumption behind