[ … ] As an empiricist I continue to think of the conceptual scheme of science as a tool, ultimately, for predicting future experience in the light of past experience. Physical objects are conceptually imported into the situation as convenient intermediaries -- not by definition in terms of experience, but simply as irreducible posits comparable, epistemologically, to the gods of Homer. Let me interject that for my part I do, qua lay physicist, believe in physical objects and not in Homer's gods; and I consider it a scientific error to believe otherwise. But in point of epistemological footing the physical objects and the gods differ only in degree and not in kind. Both sorts of entities enter our conception only as cultural posits. The myth of physical objects is epistemologically superior to most in that it has proved more efficacious than other myths as a device for working a manageable structure into the flux of experience.  [ … ]

W.O.Quine, Two Dogmas of Empiricism

Ontology does make differennce
" In a much-quoted passage in "Two Dogmas of Empiricism," Quine claims that physical objects are "comparable, epistemologically, to the Gods of Homer" (1951 p. 44). [ … ] I suggest that even if both physical objects and Homeric Gods are "posits," serving in the accommodation of experience, the two types of entities can make sense of experience in quite different ways. A theological conception of the world, Homeric or otherwise, has the capacity to yield explanations of experience that are qualitatively different from those yielded by materialist conceptions. Gods can rationalize where material objects can only causally explain."
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Peter Godfrey-Smith, Quine and a Dogma of Empiricism

Ontology as a result of the historicity of knowledge
" Scientists [ … ] are sculptors of  reality - but sculptors in a special sense. They not merely act casually upon the world [ … ]; they also create semantic conditions engendering strong inferences from known effects to novel projections and, conversely, from the projections to testable effects. [ … ] Every individual group, and culture tries to arrive at an equilibrium between the entities it posits and leading beliefs, needs, expectations, and ways of arguing. [… ] I do not assert that any combined causal-semantic action will lead to a well-articulated and livable world. The material humans [ … ] face must be approached in the right way. It offers resistance; some constructions (some incipient cultures - cargo cults, for example) find no point to attack in it and simply collapse. On the other hand, this material is more pliable that is commonly assumed. Molding it in one way (history of technology leading up to a technologically streamlined environment and large research cities like CERN), we get elementary particles; proceeding in another, we get a nature that is alive and full of gods. [ .. ]
We can tell many interesting stories. We cannot explain, however, how the chosen approach is related to the world and why it is successful, in terms of the world. This would mean knowing the results of all possible approaches or, what amounts to the same, we would know the history of the world before the world has come to an end ".

Paul Feyerabend, "Realism and the Historicity of Knowledge", Journal of Philosophy, August 1989.