194), before it had been overruled in England: and though limited as it was understood to be in Bent _v._ Baker (3 Term Rep. 34), to negotiable paper (Pleasants _v._ Pemberton, 2 Dall. 196), it has never been varied from since that time, though it has frequently been admitted that Walton _v._ Shelley was properly overruled. It ought not now to be overruled in Pennsylvania. "After the decisions cited," says Judge Rogers, in Gest _v._ Espy (2 Watts, 268), "this cannot be considered an open question, nor do we think ourselves at liberty now to examine the foundations of the rule." Unfortunately our Supreme Court have not always put this sound and wise limitation upon their own power. In the case of Post _v._ Avery (5 W. & S. 509), they declared in regard to a rule of more than thirty years' standing, and confirmed by numerous cases, that they had "vainly hoped that the inconvenience of the rule would have attracted the attention of the legislature, _who alone are competent to abolish it_;" but as nothing was to be expected from that quarter, "they were driven by stress of necessity" to overrule a case expressly decided on the authority of the rule. (Hart _v._ Heilner, 3 Rawle, 407.) And two years afterwards, after having made the remarkable declaration that the legislature alone was competent to abolish the rule, they nevertheless pronounced it "exploded altogether." (McClelland _v._ Mahon, 1 Barr, 364.) Lord Bacon says of retrospective laws: "_Cujus generis leges raro et magna cum cautione sunt adhibenda: neque enim placet Janus in legibus._" Without any saving clause may the epithet and denunciation be applied to judicial laws. They are always _retrospective_, but worse on many accounts than _retrospective statutes_. Against the latter we have at least the security of the constitutional provision that prohibits the passage of any law, which impairs the obligation of a contract, executory or executed; and it has been well held that this prohibition applies to such an alteration of the law of evidence in force at the time the contract was made, as would practically destroy the contract itself by destroying the only means of enforcing it. There is no such constitutional provision against judicial legislation. It sweeps away a man's rights, vested, as he had reason to think, upon the firmest foundation, without affording him the shadow of redress. Nor could there, in the nature of things, be any such devised. When a court overrules a previous decision, it does not simply repeal it; it must pronounce it never to have been law. There is no instance on record, in which a court has instituted the inquiry, upon what grounds the suitor had relied in investing his property or making his contract, and relieved him from the disastrous consequences, not of his, but of their mistake, or the mistake of their predecessors. The man who, on the faith of Steele _v._ The Ph[oe]nix Ins. Co. (3 Binn. 306), decided in 1811,