An ontological claim to truth is meaningless

Assumption 1: A philosophy consists of establishing a set of propositions as valid.

Assumption 2: There exist philosophies that (implicitly) claim, "This philosophy is ontologically true," while in fact, they are not ontologically true.

Assumption 3: For someone to claim beyond doubt that they possess an ontologically true philosophy, they must first assume that "ontology/mind-independence" exists and that more than its mere existence can be recognized with certainty. Furthermore, self-reference must be permitted.

Conclusion (following these assumptions):

Ontological truth is merely another assumption and is not necessary for the practice of philosophy. If ontological truth is just an assumption, attributing it to a system is futile.

Against the objection of performative contradiction: It is not claimed that this thesis is ontologically true. On the contrary, it is asserted that by establishing these assumptions, ontological truth claims become meaningless.

Furthermore I contend that ontological truth claims are not even necessary to practice philosophy.