In the present paper, I will defend three theses. Firstly, the antirealism ‒from Kant to postmodernism‒ stems from the confusion between ontology (what there is) and epistemology (the way in which we know or represent what there is). Secondly, this antirealism is a form of transcendental idealism, because it takes epistemology as the condition of possibility of ontology. And thirdly, the new realism (post-postmodern realism) is both a metaphysical realism, because it takes the ontology to be independent of epistemology (what I call “negative realism”), and a transcendental realism, because it considers ontology the condition of the possibility of epistemology (what I call “positive realism”)