Ah, an arbitrary assertion. We don't get NEARLY enough of those around here.
:-)
By "validated," I mean established by cognitive means other than conceptual
argument from premises. Validation is a broader concept, and applies to
basic conceptual identification of perceptual entities, for example. We
can't prove, in a formal sense, that we are in pain when we drop a rock on
our foot, but WE know, and can validate the claim that we are in pain by
direct experience. If we limit beliefs to those that can be proved via the
mode of formal arguments, we can't get anywhere because we can never
establish any premises. But, like proof, validation has standards, which is
one reason why there are so many disagreements among witnesses as to what
happened in auto accidents, etc.; people's standards differ (as well as do
their abilities with respect to actually perceving what is going on). The
point of my claim is that there are some premises that cannot be proved but
that can be validated objectively, and then used to prove other things. One
such is that one exists. You cannot prove, in a premise-conclusion sense,
that you exist, but you can provide others with evidence of your existence
that validates the idea that you do exist, and, of course, you have plenty
of evidence to validate it for yourself. You can't PROVE to yourself that
you exist because you have already assumed that you exist in the very act of
wondering whether you can prove it. Thus all such attempted proofs would be
circular. But, since you can't, even in principle, prove that you exist,
does that mean that you don't, or that you don't know that you do? No.