The classical Roman law denied relief on account of mistake of law except in the case of minors and women.31 But in most the ground of decision and sometimes merely in discussion or argument, it has been said that there is no established rule forbidding the giving of relief to one injured by reason of a mistake of law, but that whenever it is clearly shown that parties in their dealings with each other have acted under a common mistake of law and the party injured thereby can be relieved without doing injustice to others, equity will afford him redress. Lawrence County Bank v. Arndt, 69 Ark. 406, 65 S. W. 1052; Freichnecht v. Meyer, 39 N. J. Eq. 551; Ryder v. Ryder, 19 R. I. 188, 32 Atl. 919; Hausbrandt v. Hofler, 117 Iowa, 103, 90 N. W. 494, 94 Am. St. Rep. 289, quoting and following Stafford v. Fetters, 55 Iowa, 484, 8 N. W. 322, and Ring v. Ashworth, 3 Iowa, 452; Snell v. Insurance Co., 98 U. S. 85, 25 L. Ed. 52. To the same effect see Swedesboro L. & B. Assoc. v. Gans, 20 Dick. 132, in which the old rule as to ignorance of the law is said to be subject to so many exceptions that it is quite as often inapplicable as applicable; Williams v. Hamilton, 104 Iowa, 423, 73 N. W. 1029, in which the court declares it to be well settled that a mistake as to law may under certain circumstances afford ground (or relief in equity; and Allcard v. Walker, [1896] 2 Ch. 369, 381, in which the proposition that relief never can be given in respect to a mistake of law was called inaccurate. So it has been said that the important question was not whether the mistake was one of law or of fact, but whether the particular mistake was such as a court of equity will correct, and this depends upon whether the case falls within the fundamental principle of equity that no one shall be allowed to enrich himself unjustly at the expense of another'by reason of an innocent mistake of law or of fact entertained by both parties. Park Brothers v. Blodgett, 64 Conn. 28, 29 Atl. 133; Blakemore v. Blake-more, 19 Ky. L. Rep. 1619, 1620, 44 S. W. 96; Dinwiddie v. Self, 145 I11. 290, 305, 33 N. E. 892; Benson v. Bunting, 127 Cal. 532, 59 Pac. 991; Order of United Commercial,. etc., of America v. McAdam, 125 Fed. 358, 368, 61 C. C. A. 22; Stone v. Godfrey, 5 DeG. M. & G. 76, 90; Naylor v. Winch, 1 Sim. & Stu. 555, 564; Re Saxon life, etc., Soc., 2 Johns & Hen. 408, 412. This doctrine frequently has been applied to cases of the reformation of contracts; a fortiori, it is to be applied to cases in which justice can be obtained only by a complete rescission. Canedy v. Marcy, 13 Gray, 373; Stockbridge Iron Co. v. Hudson Iron Co., 107 Mass. 290, 299; Griswold v. Hazard, 141 U. S. 260, 35 L. Ed. 678, 11 Sup. Ct. 972, and cases cited on page 284. Carrell v. McMurray, 136 Fed. 661. Cases in which a release has been either avoided or restricted in its operation by a limitation of its general words rest really upon the same principle. Rams-den v. Hylton, 2 Ves. Sen. 304; Lyall v. Edwards, 6 H. & N. 337; Turner v. Turner,.14 Ch. D. 829; In re Garnett, 31 Ch. D. 1. So one who has made an election under a. will may rescind it upon proof that he acted under a misapprehension of his legal rights or even in ignorance of the fact that he was bound to make an election. Watson v. Watson, 128 Mass. 152; Macknet v. Macknet, 29 N. J. Eq. 54; Pusey v. Desbouvrie, 3 P. Wins. 315, 316; Salkeld v. Vernon, 1 Eden, 64." "Dig. XXII, 6, 9, pr. and Sec.2, Civil law countries any distinction between mistake of law and mistake of faet, has now been disregarded. The German Code makes no difference32 the French 33 and Italian law *4 likewise put mistake of law on the same footing as mistake of fact, and such is the general modern tendency,85