Perhaps, therefore, it may be concluded from the precedent reasoning, that the evidence of all ancient history must now be lost; or at least, will be lost in time, as the chain of causes encreases, and runs on to a greater length.

But as it seems contrary to common sense to think, that if the republic of letters, and the art of printing continue on the same footing as at present, our posterity, even after a thousand ages, can ever doubt if there has been such a man as JULIUS CAESAR; this may be considered as an objection to the present system.

If belief consisted only in a certain vivacity, conveyed from an original impression, it would decay by the length of the transition, and must at last be utterly extinguished: And vice versa, if belief on some occasions be not capable of such an extinction; it must be something different from that vivacity.
Before I answer this objection I shall observe, that from this topic there has been borrowed a very celebrated argument against the Christian Religion; but with this difference, that the connexion betwixt each link of the chain in human testimony has been there supposed not to go beyond probability, and to be liable to a degree of doubt and uncertainty.
And indeed it must be confest, that in this manner of considering the subject, (which however is not a true one) there is no history or tradition, but what must in the end lose all its force and evidence.
Every new probability diminishes the original conviction; and however great that conviction may be supposed, it is impossible it can subsist under such re-iterated diminutions.

This is true in general; though we shall find [Part IV.Sect.

1.] afterwards, that there is one very memorable exception, which is of vast consequence in the present subject of the understanding.
Mean while to give a solution of the preceding objection upon the supposition, that historical evidence amounts at first to an entire proof; let us consider, that though the links are innumerable, that connect any original fact with the present impression, which is the foundation of belief; yet they are all of the same kind, and depend on the fidelity of Printers and Copyists.