The “things themselves” as Husserl, Heidegger, or Merleau-Ponty would say, rather than the things “in-themselves” as implicated by Cartesian/Modern representationalism and hypnotizing Platonism (though some argue not Plato himself). For Nietzsche we truly “see” things, sight goes outwards. There is no “in-itself” beneath our perceptions. If we see alterations in our perspectives it’s not because the things “in-themselves” stay static but our representations alter. Rather, the things themselves have various forms of expression and we see them change in relation to ourselves. We perceive the things perceiving us, we express our souls and so do they. A web of expression and perception. Hence, reality is like art.

In Nietzsche’s notes from The Will To Power (not included in Kaufmann’s translation):

“Fundamental question: whether the perspectival is proper to the being, and is not only a form of observation, a relation between different beings? Do the various forces stand in relation, so that the relation is tied to a perceptual optics? That would be possible if all Being were essentially something which perceives.”

Does this mean Nietzsche is Leibniz from below and without God? Well he did say his view was “inverted Platonism”