Harman argues that philosophy must shift away from the human subject and towards the object. He does this by radicalising Heidegger's thesis on das Zeug (equipment) and Zuhandenheit (readiness-to-hand). The usual way of reading these sections of Being and Time, as Harman himself admits, is to express the priority of pragmatic lived experience over theoretical, abstracted descriptions. When we encounter a doorway, we do not encounter a wooden construction of certain dimensions, but something we may walk through and which articulates a threshold between two spaces we may cross and inhabit (e.g. the outside and the warmth of the house, or the cold, unforgiving corridor and the intimidating office of the lecturer...)
For Harman, this reading is superficial even if it was probably Heidegger's own. In Speculative Realist terms, equipment or 'tool-being' does not relate specifically to human praxis but to any interaction between objects whatsoever. The encounter between a human student and the doorway of a lecturer's office is not philosophically more unique or special than the encounter between a dust mote and the door. Indeed, throughout his work, Harman insists we cannot 'continue to lump together monkeys, tornadoes, diamonds, and oil under the single heading of that which lies outside' . The event of 'relation' which occurs between human being and tree, say, is no more important or structurally unique than the relation between tree and earth, or tree and carbon monoxide, or tree and house (or whatever).
"The event of 'relation' which occurs between human being and tree, say, is no more important or structurally unique than the relation between tree and earth, or tree and carbon monoxide, or tree and house (or whatever)."
That describes deprivation. Being unable to see how different human perception is to biological or geological classification amounts to a kind of blindness. I think the usual term is "reductionism" but maybe someone has come up with a better one. It's the equivalent of a kind of tone-deafness.
MH has given us some 'music' to sing. But first one must have an ear for such music.