Heraclitus himself says, ἦθος ἀνθρώπῳ δαίμων, "The (familiar) abode for humans is the open region for the presencing of god (the unfamiliar one)."

If the name "ethics," in keeping with the basic meaning of the word f,Ooc,, should now say that ethics ponders the abode of the human being, then that thinking which thinks the truth of being as the primordial element of the human being, as one who eksists, is in itself originary ethics. However, this thinking is not ethics in the first instance because it is ontology. For ontology always thinks solely the being (ὄν) in its being. But as long as the rruth of being is not thought all ontology remains without its foundation. Therefore the thinking that in Being and Time tries to advance thought in a preliminary way into the truth of being characterizes itself as "fundamental ontology." It strives to reach back into the essential ground from which thought concerning the truth of being emerges. By initiating another inquiry this thinking is already removed from the "ontology" of metaphysics (even that of Kant). "Ontology" itself, however, whether transcendental or precritical, is subject to critique, not because it thinks the being of beings and in so doing reduces being to a concept, but because it does not think the truth of being and so fails to recognize that there is a thinking more rigorous than conceptual thinking. In the poverty of its first breakthrough, the thinking that tries to advance thought into the truth of being brings only a small pan of that wholly other dimension to language. This language even falsifies itself, for it does not yet succeed in retaining the essential help of phenomenological seeing while dispensing with the inappropriate concern with "science" and "research." But in order to make the attempt at thinking recognizable and at the same time understandable for existing philosophy, it could at first be expressed only within the horizon of [188 {GA 9 357}] that existing philosophy and the use of its current terms.

In the meantime I have learned to see that these very terms were bound to lead immediately and inevitably into error. For the terms and the conceptual language corresponding to them were not rethought by readers from the matter particularly to be thought; rather, the matter was conceived according to the established terminology in its customary meaning. The thinking that inquires into the truth of being and so defines the human being's essential abode from being and toward being is neither ethics nor ontology. Thus the question about the relation of each to the other no longer has any basis in this sphere. Nonetheless, your question, thought in a more original way, retains a meaning and an essential importance.

For it must be asked: If the thinking that ponders the truth of being defines the essence of humanitas as ek-sistence from the latter's belongingness to being, then does thinking remain only a theoretical representation


Martin Heidegger (GA 9) Letter on Humanism - Pathmarks