Scattered throughout Heidegger’s writings are some puzzling distinctions. For instance, in “The Question Concerning Technology,” Heidegger claims that the essence (Wesen) of technology is nothing technological. 
In the lecture “The Danger,” Heidegger claims that the essence of death has nothing to do with “hundreds of thousands” dying “en masse” in “extermination camps” and man-made famines.  The essence of death, in short, is not to be found in actual deaths.
In “Language and the Poem: A Discussion on Georg Trakl’s Poetic Work,” Heidegger claims that pain’s “essence remains closed to every thinking that represents pain in terms of sensations.”  In other words, the essence of pain is not to be found in sensations.
In “Language,” Heidegger also claims that “In its essence, language is neither expression nor an activity of man.”  The essence of language, then, is not to be found in actual speech.
In “Building, Dwelling, Thinking,” Heidegger claims that “however hard and bitter, however hampering and threatening the lack of houses remains, the real plight of dwelling does not lie merely in the lack of houses.”  The essences of dwelling and homelessness are something different than having or lacking a home.
Heidegger also asserts some puzzling identities.
For instance, in Introduction to Metaphysics, Heidegger claims that Soviet Russia and the United States “are both, metaphysically speaking [i.e., in essence] the same: the same dreary frenzy of unleashed technology [Technik] and the regimentation of rootless and normalized men.” 
In “The Danger,” Heidegger writes: “Agriculture is now a mechanized food industry—in essence the same [im Wesen das Selbe] as the manufacturing of corpses in gas chambers and extermination camps, the same as the blockading and starving of nations, the same as the manufacture of hydrogen bombs.” 
What sort of thinking allows Heidegger to draw such distinctions and assert such identities? The answer, of course, is philosophical thinking. Drawing a distinction between an entity and its essence is as old as Plato. Once Heidegger asserts a difference between a being and its essence, he is then in a position to assert that different beings are the same “in essence” because they are part of the historical period. This idea has its roots in the rise of modern philosophical historicism.
In Plato’s Euthyphro, Socrates asks Euthyphro to spell out the idea or the essence of piety: “teach me whatever this idea itself is, so that by gazing at it and using it as a pattern, I may declare that whatever is like it, among the things you or anyone else may do, is pious, and that whatever is not like it is not pious” (6d–e).  Knowing the essence of piety allows us to sort pious and impious acts. Pointing to an example of a pious act is not enough, because Socrates wants to know what makes it possible to point out an example of piety in the first place. So the essence of piety is different from pious acts. The essence of piety is neither pious or impious.
The same is true of every other essence. Knowing the essence of dogs allows us to sort dogs from foxes. But the essence of dogs is not a particular dog. Knowing the essence of courage allows us to distinguish courage and cowardice. But the essence of courage is not a courageous act.
Or, to put it in general terms: Knowing Being, the essence of what it is to be, allows us to distinguish beings from non-beings. But Being itself is not a being. This, of course, is Heidegger’s famous doctrine of the “ontological difference”: “The Being of beings ‘is’ not itself a being.” 
The puzzling distinctions listed above are simply examples of the ontological difference: The essence of technology is not a machine; the essence of death is not a particular death; the essence of pain is not a sensation; the essence of language is not speech; the essence of dwelling is not a house; the essence of homelessness is not simply lacking a house; the essence of destruction is not being blown up; and so forth.
But what licenses a philosopher to speak this way? There are experts in every field of phenomena. A philosopher, insofar as he is a philosopher, cannot claim to have greater knowledge than these experts. For instance, philosophers do not know more about living things than biologists. Philosophers know less about healing the sick than doctors. Philosophers know less about strategy than generals and less about courage than infantrymen. Philosophers know less about pain than physiologists or people who have suffered greatly. Philosophers have less expertise about dwelling than people who build houses and about homelessness than those who operate homeless shelters. And so forth.
The expertise of the philosopher lies in taking a step back from all these fields and asking the experts how they know what they know. Because experts get so involved in straightforwardly knowing and doing particular things that they don’t even wonder about how they are doing it, or where they as human beings fit into the picture. By talking about the essences of technology, death, pain, language, dwelling, and so forth, Heidegger tries to make us wonder about how the world shows up to us. That is the job of the philosopher.
Heidegger believed that how the world shows up to us changes from time to time. For the ancient Greeks, things showed up as having an independent existence that eluded our complete understanding and control. For moderns, things show up to us as transparent to our understanding and available for control and consumption. Heidegger called the modern way of seeing the world the essence of technology. It is a way of seeing the world that makes modern science and technology possible. This is the basis for Heidegger’s claims that the United States and the Soviet Union, or factory farms and extermination camps, are metaphysically the same.
Now, a layman might object to Heidegger’s views as follows. When Heidegger claims that the essence of homelessness is different from actual homelessness, isn’t this just a bit insensitive to the homeless? When Heidegger remarks that the essence of pain is different from actual pain, isn’t that insensitive to people who are actually suffering? If the essence of death is different from actual deaths, even spectacularly horrible deaths, isn’t that insensitive to everyone who has ever lost a loved one?
But these objections are based on simple misunderstandings. First, when Heidegger mentions extermination camps, man-made famines, mass homelessness, and atomic bombs in the years after the Second World War, he is obviously appealing to pathos. He is evoking deep feelings in his audiences, many of whom suffered personally from the very things he names.
But the task of philosophy is not to console the suffering. That is the work of doctors, priests, therapists, and social workers. Heidegger has no expertise in such matters. The task of philosophy is to take a step back from homelessness, pain, and death and raise questions about their meaning, their essences. And that is why people read Heidegger. They don’t come to him for a cup of chamomile tea and a shoulder to cry on.
One might also object that claiming that the United States and the Soviet Union are metaphysically the same overlooks the fact that life was better in the USA than the USSR. Surely there are lots of important moral differences between liberal democracy and totalitarianism. Likewise, the claim that factory farms are in essence the same as extermination camps, man-made famines, and hydrogen bombs seems a bit insensitive to humans who might resent being compared to pesticides, chemical fertilizers, and feedlots. Isn’t there a vast moral gulf between using technology to feed millions and using technology to murder millions?
But again, these objections are based on an elementary error. Heidegger is not saying that the US and the USSR, or factory farming and man-made mass death, are morally equivalent. He is not, like Isaac Bashevis Singer, claiming that for farm animals, every day is Auschwitz, which is meant as a moral equivalence. Heidegger is saying that these horrors are metaphysically equivalent. Moral and metaphysical equivalence are simply two different questions. So claiming that these phenomena are metaphysically the same does not commit one to claiming that they are morally the same.
Heidegger is not the clearest writer, but his ideas of the ontological difference between beings and Being, and of the stark differences between the Greek and the modern worldviews, can be understood by any moderately intelligent layman. I explained them above in barely a thousand words. So there is really no excuse for Heidegger scholars who ignore these distinctions in order to abuse Heidegger in what amounts to politically correct rituals of execration to appease his critics on the Left. Frequently, they sound like they are running for office.
For instance, John D. Caputo calls Heidegger’s distinction between the essences and the phenomena of pain, homelessness, and mass death “essentialization.” Caputo characterizes essentialization as “thoughtless, tasteless, offensive,”  “tasteless, insensitive, scandalous—thoughtless . . . grotesque and dangerous,”  an “obscenity,”  and even a “reductio ad absurdum”  of Heidegger’s thought. Essentialization:
accounts for a good deal of Heidegger’s habit of saying the most shocking and insensitive—which means unfeeling—things about living things: that real destructiveness is not found in the universal incineration of all life, human and otherwise, but the loss of a Schwartzwaldian Ding [Black-Forest thing]; that real homelessness is not a matter of children freezing on winter streets but the loss of a sense of Wohnen [dwelling]; that agricultural technology and gas chambers are “essentially the same” . . . It belongs to the essence of Heideggerian Wesen [essence] to neutralize the distinction between life and death, to raise itself up to such a point of transcendental purity that it can no longer tell the difference between agriculture and murder. 
The reader already knows enough to refute this tirade. Caputo is ignoring the difference between metaphysical and moral sameness. He claims that distinguishing between the essence of pain and sensations of pain is the same thing as denying that sensations are real, which does not follow at all. Caputo accuses Heidegger of aestheticism, asceticism, and even anestheticism (as in anesthesia) for distinguishing between pain and its essence. But Heidegger’s real crime is simply being a philosopher. Philosophers do not deny the existence of bodies in pain. They deny only that the essence of pain hurts.
For Caputo, however, the crime of being a philosopher is to reflect on human suffering—as opposed, I guess, to doing something about human suffering. “Doing something” like signaling how much he cares in the pages of philosophy journals:
What if one were to say that what essentially calls to us in homelessness is not the essence of dwelling but the cries of those who suffer from lack of shelter? What if the call were really a cry of grief? What if the call were the appeal for help of those who suffer? What if the summons by which we are summarily called were the summons for aid by the victim? What if responding to the appeal of the victim were the oldest responsibility of all? 
This, of course, is a legitimate response to human suffering. It is also the first response to human suffering. It is the response of concerned citizens, global humanitarians, policemen, firemen, emergency medical technicians, doctors, nurses, priests, therapists, councilors, and social workers. But it is not the philosophical response to suffering, which first and foremost is to understand. Thus Caputo’s indictment of Heidegger is basically that he chose to be a philosopher, not a social worker.
Note that Caputo does not claim that distinguishing between the essence of language and human speech denies the reality of human speech. Nor does it trigger torrents of abuse. Caputo is only focusing on emotional hot-button issues: pain, homelessness, mass death. Thus his position is basically that only these issues should be off-limits to philosophical reflection, because to philosophize about the greatest problems facing humanity is somehow in bad taste.
When reading some of Heidegger’s more pedestrian-minded detractors, one often wonders: Why Heidegger? What attracted them to Heidegger in the first place? For instance, Richard Rorty writes:
One might think that the destruction of the earth and the standardization of man were bad enough . . . without bringing in the world of the spirit at all. But this would be to treat “forgetfulness of being” as just a handy label for whatever it is that has been going wrong lately . . . This way of putting things may suggest that I am, like a good modern, neglecting the “ontological difference” between Being and beings. But [when talking about the problems of modernity] Heidegger neglected it too—and it is well for him that he does. 
Heidegger evoked the crises of the post-War age to draw people into his philosophical reflections. Then he asked them to take a step back from engagement with the problems of the world and reflect a bit on their meaning. But, as Heidegger himself pointed out, to dispense with the reflective turn and leave it at “Mankind has entered the atomic age” is not to rise above the platitudes of illustrated newsmagazines.  For Rorty, though, that is all well and good. So why Heidegger?
Years ago, I submitted an essay on Nietzsche to a philosophy journal. It was rejected, and when I read the peer reviewer’s report, it was clear that he actually had no objections to my discussion of Nietzsche—beyond the fact that he would have preferred that I had written a paper on John Rawls instead. This is a very common vice in academia. Instead of criticizing a writer for what he has actually written, he is attacked for not writing what his critic would have preferred he had written. They want to change the subject. But they don’t just come out and say so, because then they would have no actual grounds to criticize you.
Caputo and Rorty don’t really want to engage Heidegger philosophically. They simply wish he were someone else, someone more like them. Philosophy, however, is fundamentally different from passionate engagement with the problems of mankind. Philosophy begins with reflective disengagement and then ponders the meanings of things, even things that we would like to abolish, like pain, homelessness, and mass murder.
But what if this reflective turn reveals that the deep metaphysical assumptions of liberal democracy are the same as communist and fascist totalitarianism? And what if allowing these assumptions to go unchallenged dooms liberal democracy into becoming nothing more than a soft totalitarian dystopia?
This is why Heidegger matters. This is why even academic Leftists who would prefer to simply change the subject and focus on politics need to take a step back and reflect on the meaning of what they are doing.
Philosophical reflection itself changes nothing. But we can’t philosophize forever. We have to return to life. And when we do, philosophy allows us to see the world, its problems, and our tasks in a new light. And seeing the world anew can change everything. This is why we need to let Heidegger be Heidegger.
  Martin Heidegger, “The Question Concerning Technology,” in The Question Concerning Technology and Other Essays, ed. and trans. William Lovitt (New York: Harper and Row, 1977), p. 4.
  Cited by Thomas Sheehan in “Heidegger and the Nazis,” New York Review of Books, June 16, 1988, p. 42, n69. This lecture has been translated in Heidegger’s Bremen and Freiburg Lectures: Insight into That Which Is and Basic Principles of Thinking, trans. Andrew J. Mitchell (Bloomington: Indiana University Press, 2012).
  Heidegger, “Language and the Poem: A Discussion on Georg Trakl’s Poetic Work,” in On the Way to Language, trans. Peter D. Herz (New York: Harper and Row, 1971), esp. p. 181.
  Heidegger, “Language,” in Poetry, Language, Thought, ed. and trans. Albert Hofstadter (New York: Harper and Row, 1971), p. 197, cf. pp. 192–94.
  Heidegger, “Building, Dwelling, Thinking,” in Poetry, Language, Thought, p. 161.
  Heidegger, “The Thing,” in Poetry, Language, Thought, p. 166.
  Heidegger, “Memorial Address,” in Discourse on Thinking, trans. John M. Anderson and E. Hans Freund (New York: Harper and Row, 1966), esp. p. 56.
  Heidegger, An Introduction to Metaphysics, trans. Ralph Manheim (New Haven: Yale University Press, 1959), p. 37.
  Quoted in Wolfgang Schirmacher, Technik und Gelassenheit (Freiburg: Alber, 1983), p. 25, which in turn cites p. 25 of the original typescript.
  Plato, Euthyphro, in Plato and Aristophanes, Four Texts on Socrates, ed. and trans. Thomas G. West and Grace Starry West (Ithaca: Cornell University Press, 1984), p. 48.
  Heidegger, Being and Time, trans. John Macquarrie and Edward Robinson (New York: Harper and Row, 1962), p. 26.
  John D. Caputo, “Thinking, Poetry, and Pain,” in Heidegger and Praxis, ed. Thomas J. Nenon, The Southern Journal of Philosophy 27, Supplement (1989), p. 169.
  Ibid, p. 179.
  Caputo, “Incarnation and Essentialization: A Reading of Heidegger,” Philosophy Today, 35 (1991), p. 41.
  Ibid.
  Ibid, pp. 40–41.
  Caputo, “Thinking, Poetry, and Pain,” p. 272.
  Richard Rorty, “Overcoming the Tradition: Heidegger and Dewey,” Consequences of Pragmatism: Essays 1972–1980 (Minneapolis: University of Minnesota Press, 1982), p. 48.
  Heidegger, The Principle of Reason, trans. Reginald Lilly (Bloomington: Indiana University Press, 1991), pp. 121–24.