10. Traditional testimonies, the further removed the less their proof becomes.
This is what concerns assent in
matters wherein testimony is made use of: concerning which, I think, it may not be amiss to take notice of a rule
observed in the law of England; which is, That though the attested copy of a record be good proof, yet the copy of
a copy, ever so well attested, and by ever so credible witnesses, will not be admitted as a proof in judicature. This
is so generally approved as reasonable, and suited to the wisdom and caution to be used in our inquiry after
material truths, that I never yet heard of any one that blamed it. This practice, if it be allowable in the decisions of
right and wrong, carries this observation along with it, viz., That any testimony, the further off it is from the
original truth, the less force and proof it has. The being and existence of the thing itself, is what I call the original
truth. A credible man vouching his knowledge of it is a good proof; but if another equally credible do witness it
from his report, the testimony is weaker: and a third that attests the hearsay of an hearsay is yet less considerable.
So that in traditional truths, each remove weakens the force of the proof: and the more hands the tradition has
successively passed through, the less strength and evidence does it receive from them. This I thought necessary to
be taken notice of: because I find amongst some men the quite contrary commonly practised, who look on
opinions to gain force by growing older; and what a thousand years since would not, to a rational man
contemporary with the first voucher, have appeared at all probable, is now urged as certain beyond all question,
only because several have since, from him, said it one after another. Upon this ground propositions, evidently
false or doubtful enough in their first beginning, come, by an inverted rule of probability, to pass for authentic
truths; and those which found or deserved little credit from the mouths of their first authors, are thought to grow
venerable by age, are urged as undeniable.
