a note about doing ontology
“Metaphysics,” as traditionally conceived, is a mythical—>conceptualist (pre-scientific) approach to realism. I call that metaphysicalism. It’s what Heidegger set out to deconstruct.
But there’s a sense of metaphysics that’s unavoidable: meta-physics, in the literal sense, which perhaps becomes philosophy of mathematics (as, e.g., we humans don’t yet have the mathematical capacity to describe quantum foam; see Lee Smolin, Three Roads to Quantum Gravity, 2001). Worries about realism in mathematics are no metaphysicalism, since we’re in the “same” universe with other, yet-undiscovered forms of intelligent life (SETI optimist here).
Also, people aren’t doing metaphysicalism in The Oxford Handbook of Metaphysics (2003), which is concerned with basic conceptuality, but with respect to (relative to) scientific realism (including neurocognitive science or biology of mind à la John Searle).
So, it turns out (historically—evolutionarily) that metaphysicalism was an unrealistic way to do ontology. Ontology is not doable relative to the history of “metaphysics”. But there’s no escaping ontological implicatures. What’s the nature of functions in biology? What are species or natural kinds? One may have an untenable view of these, but there’s no escaping ontological implicature.
Ontology is a kind of inquiry, not a particular result. One may have overt ontological commitments or not. The work of Habermas, in particular, doesn’t require ontological commitments, even as it gets real about its fundamental implicature.