an objective fact is never enough to establish that fact. The chances of falsehood or error are so many, the conditions which gave rise to the statement are so little known, that we cannot be sure that none of these chances has taken effect. The critical examination provides no definitive solution; it is indispensable if we are to avoid error, but it is insufficient to conduct us to truth.
Criticism can prove no fact; it only yields probabilities. Its end and result is to decompose documents into statements, each labelled with an estimate of its value—worthless statement, statement open to suspicion (strong or weak), statement probably (or, very probably) true, statement of unknown value.
Of all these different kinds of results one only is definitive—the statement of an author who can have had no information on the fact he states is null and void; it is to be rejected as we reject an apocryphal document. But criticism here merely destroys illusory sources of information; it supplies nothing certain to take their place. The only sure results of criticism are negative. All the positive results are subject to doubt; they reduce to propositions of the form: "There are chances for or against the truth of such and such a statement." Chances only. A statement open to suspicion may turn out to be true; a statement whose truth is probable may, after all, be false. Instances occur continually, and we are never sufficiently well acquainted with the conditions under which the observation was made to know whether it was made ill or well.
In order to obtain a definitive result we require a final operation. After passing through the ordeal of criticism, statements present themselves as