The paper is the summary of a wider work, a research program. The hypothesis is that if Fundamental Ontology is apophatic – that is, if it has the same dialectical nature (relationality-substantiality) as the Trinity – we can accept that Trinity is also apophatic. The apophatic-relational explanation may sound odd, but it is the most honest one, because it does not hide the problems under the carpet. What emerges is a coherent form of Trinitarian Theism – since there is correspondence (...) between the human (un)ability to know the two levels of reality (the World and God) – that is based on an inevitable relational-apophatic paradigm. The apophaticism that we see in the Trinity (and in ontology) ensures that Trinitarian Theism can neither be proven nor disproven. (shrink)