An Essay Concerning Humane Understanding, Volume 2: MDCXC, Based on the 2nd Edition, Books 3 and 4
John Locke · en
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.
11. Yet History is of great Use.