Every truth about a given existent(s) reduces, in basic pattern, to: “X is: one
or more of the things which it is.” The predicate in such a case states some
characteristic(s) of the subject; but since it is a characteristic of the
subject, the concept(s) designating the subject in fact includes the
predicate from the outset. If one wishes to use the term “tautology” in this
context, then all truths are “tautological.” (And, by the same
reasoning, all falsehoods are self-contradictions.)
When making a statement about an existent, one has, ultimately, only two
alternatives: “X (which means X, the existent, including all its
characteristics) is what it is”—or: “X is not what it is.”
The choice between truth and falsehood is the choice between “tautology” (in
the sense explained) and self-contradiction.
In the realm of propositions, there is only one basic epistemological
distinction: truth vs. falsehood, and only one fundamental issue: By
what method is truth discovered and validated? To plant a dichotomy at the base
of human knowledge—to claim that there are opposite methods of
validation and opposite types of truth [as do the advocates of the
“analytic-synthetic” dichotomy] is a procedure without grounds or
justification.