[Footnote 318: "One witness (if credible) is _sufficient_ evidence to the jury of any single fact, though undoubtedly the concurrence of two or more corroborates the proof. Yet our law considers that there are many transactions to which only one person is privy; and therefore does not _always_ demand the testimony of two which the civil [and ecclesiastical] law universally requires. '_Unius responsio testis omnino non audiatur._' To extricate itself out of such absurdity, the modern practice of the civil law courts has plunged itself into another. For, as they do not allow a less number than two witnesses to be _plena probatio_, they call the testimony of one, though never so clear and positive, _semi-plena probatio_ only, on which no sentence can be founded. To make up, therefore, the necessary complement of witnesses, when they have one only to a single fact, they admit the party himself (plaintiff or defendant) to be examined in his own behalf; and administer to him what is called the _suppletory_ oath; and if his evidence happens to be in his own favour, this immediately converts the half proof into a whole one."--BLACKSTONE, _Commentaries_, III, 370. _Cf._ also BISHOP, _Marriage, Divorce, and Separation_, II, § 456; _Law Review_, I, 378, 379.] [Footnote 319: _Law Review_, I, 379, 380. See the illustrative case of Evans _v._ Evans in _Notes of Cases in Ecc. and Mar. Courts_, II (1842-43), 470-76. _Cf._ BISHOP, _op. cit._, I, § 1532; BURN, _Ecc. Law_, II, 503_e_-503_g_.]