The Principle upon which this Resumption is made, is, because the Progress of a Pestilence may be stopt at any time, _by strictly preventing all Intercourse of infected Places with the Neighbourhood_. He brings as a Proof of this lusty Assertion, what has lately happened in the raging Plague at _Marseilles_; and alledges, that it has been effectually confined to that miserable Town, by keeping careful Guard. But alas! this Argument is out of doors. Happy were it for the People of _France_ if they had greater Assurance of their Safety, than they can draw from such vain Promises of Insuring Physicians. And therefore his Objection remains in full Force, without any Satisfaction being given to it. I know from whence he took this Difficulty, but he ought to have been well satisfied that he had brought a full Solution to so powerful an Argument against all manner of _Contagion_. I will only repeat the Difficulty, and leave the clearing of it to the Patrons of a Pestilence being begot by _Contagion_; especially that it is a Step towards Dr. _Mead_’s next propagating Cause. It is asserted by those who oppose this _Contagion_, that a Plague is sometimes bred without it, otherwise it would be perpetual. This Assertion is made good, by considering a Country where a new Plague is broken out; and ask us, whether it be just then bred in that Country, or brought thither from elsewhere? If we grant the first, then indeed adieu to all _Contagion_: If the last, they bid us name the originary Place, where it was bred: Which would oblige us to the same Concession as the former. Therefore, say they, _Contagion_ may _propagate_ but not _begin_ a Plague.