Ideas are not true because they are old, though they may be old because they are true. The paradox is that how long a given idea has been around is of no use in proving its truth, and past staying-power is not cause for something to continue to stay.
Tradition is not self-certifying evidence of truth, but a testament to those who passed along what they believe to be true. All things being equal, we ought certainly defer to timeworn truths — but the moment a persuasive argument can be made for change, the fact that something remained unchanged prior to the new argument cannot be used in its defense. New evidence always takes us back to the question itself.
That new evidence may arise not from a new fact arising, but from a new way of seeing the question — whether a social construct or a novel philosophical paradigm. And in the long run, the truth itself — the dogma or theory — may remain relatively untouched, but be understood and expressed in new ways. The best and most vital doctrines — the deepest truths — are capable of such costume changes.
But just as antiquity is no proof of truth, neither is novelty. There are bad old ideas and new ones. Each and all must be tested with the best tools we have at hand.
Tobias Stanislas Haller BSG