Concurring Opinion by
Spaeth, J.:I join in affirming the judgment but only because I find the trial judge’s instructions to the jury in accordance with the most recent decisions of our Supreme Court. I believe that examination of those decisions will lead to the conclusion that the law on insanity is in such a. state of uncertainty that the time has come to *98restate it. Accordingly, I respectfully express the hope that an appeal to the Supreme Court will be requested and allowed.
The Burden of Proving Insanity
A.
In the present case appellant pleaded not guilty by reason of insanity, and introduced psychiatric testimony in support of the plea, which the Commonwealth rebutted by other psychiatric testimony. In these circumstances, as the trial judge told the jury, it was the burden of appellant to prove insanity by a fair preponderance of the evidence.
It is true that Mr. Justice Roberts has expressed a different opinion in Commonwealth v. Vogel, 440 Pa. 1, 268 A. 2d 89 (1970). That opinion, however, has not secured the support of a majority of the Supreme Court.
In Commonwealth v. Vogel, supra, the Court divided four to two in support of a per curiam order reversing judgments of sentence and awarding a new trial. One opinion was by Mr. Justice (now Mr. Chief Justice) Jones, joined by Mr. Justice O’Brien; a second was by Mr. Justice Roberts ; and a third by Mr. Justice Pom-eroy. Mr. Chief Justice Bell, joined by Mr. Justice Eagen, dissented.
It appeared that the defendant had shot and killed two persons in the course of committing a robbery. Evidently there was no substantial issue regarding the facts, the trial rather depending upon the resolution of the defendant’s plea of not guilty by reason of insanity. In support of the plea the defendant produced evidence of his discharge from the Air Force because of mental illness and the testimony of three eminently qualified psychiatrists, each of whom expressed without qualification the opinion that the defendant was legally insane. In response the Commonwealth offered no evi*99dence, relying instead “upon the presumption of sanity and the testimony of various witnesses as to the circumstances surrounding the robbery and killings.” Id. at 6, 268 A. 2d at 92.
The dissenting Justices were of the view that the Commonwealth was entitled to take this position, i.e., that the jury could disregard the testimony by the three psychiatrists and assign to the evidence of the circumstances surrounding the crime such weight as it chose. Id. at 30-32, 268 A. 2d at 101. The four Justices constituting the majority of the Court were in agreement in rejecting this conclusion, Mr. Justice Jones explaining this result as follows:
“The Commonwealth argues that the verdict is supported by the presumption of sanity, and that the jury may choose to disbelieve any witness. A verdict must be based upon evidence, and a presumption is not evidence. A verdict may not be based solely upon a presumption where there is evidence which credibly contradicts the presumption. Allison v. Snelling & Snel-ling, Inc., 425 Pa. 519, 229 A. 2d 861 (1967). See Commonwealth v. Wucherer, 351 Pa. 305, 41 A. 2d 574 (1945). The function of a presumption is to reach a presumed conclusion of fact, in the absence of credible evidence to the contrary. Waugh v. Commonwealth, 394 Pa. 166, 146 A. 2d 297 (1958). When sufficient or adequate evidence is presented to prove legal insanity, the presumption of sanity disappears as a rule of law, and a verdict may not be based thereon. IX Wigmore on Evidence, §2491 (3d ed. 1940). [Footnote omitted.]
“In the case at bar, the defendant produced evidence of legal insanity, sufficient and adequate in every respect, which was neither rebutted nor contradicted nor impugned, while the Commonwealth utterly failed to produce any evidence of legal sanity. Under such circumstances, the legal presumption of sanity is not sufficient to permit, in the face of the uncontradicted evi-*100deuce of insanity, a finding of guilt. The instant record being devoid of cmy evidence which might support the verdict, such verdict cannot stand.” Id. at 14, 268 A.2d at 96.
The point on which M[r. Justice Jonhs and Mr. Justice O’Brien, on the one hand, and Mr. Justice Roberts and Mr. Justice Pomeroy, on the other, differed was with respect to what should be the burden of proof if the Commonwealth, instead of relying on the presumption of sanity, produced evidence to rebut the presumption.
Mr. Justice Jones, speaking for himself and Mr. Justice O’Brien, adopted the following position:
“Appellant herein urges that this Court should overrule the long-standing case law in Pennsylvania, and adopt the federal rule which would require the prosecution to prove sanity beyond a reasonable doubt, as an element of the crime. I cannot accept the premise that sanity is necessarily an element of every crime. To the contrary, I view insanity as being the basis upon which society offers treatment rather than punishment to one who has committed a crime. See H. Rome, M’Naghten, Durham and Psychiatry, 34 F.R.D. 93 (1964). Although every element of a crime can be established beyond a reasonable doubt, including the element of intent to do the act, insanity may still be asserted as a defense in Pennsylvania ....
“We specifically decline to adopt the federal rule as to the burden of proving sanity or insanity. The burden remains on the defendant to prove his insanity by a fair preponderance of the evidence.” Id. at 11, 268 A.2d at 95.
In contrast to this statement, Mr. Justice Roberts urged adoption of the federal rule:
“If mens rea, or intent, is an element of the crime of murder, the capacity to form that intent, i.e., legal sanity, must likewise be an element of the crime. Clear*101ly ‘it is necessary, in order to prove the intent, to show that the perpetrator was capable of forming the requisite intent.’ Bradford v. State, 234 Md. 505, 512, 200 A.2d 150, 154 (1964). I therefore cannot agree with the assertion that £[a]n individual may intentionally kill someone, with malice aforethought,’ even though he is legally insane, i.e., legally incapable of forming the intention. Legal sanity is an essential element of the crime of murder and must be an issue for the Commonwealth to prove beyond a reasonable doubt. See In re Winship, 397 U.S. 358, 90 S. Ct. 1068 (1970). Thus I believe that the trial court was in error in the instant case when it charged the jury that the burden was on the defendant to prove by a preponderance of the evidence that he was not sane. This charge, in effect, required the defendant to disprove an element of the crime of murder and I do not believe this to be proper.
“I would adopt the rule which is now in effect in at least twenty-two of the States and in the federal courts. See cases cited in 17 A.L.R. 3d 158-59. These jurisdictions, taking for granted that most men are sane, do not initially require the prosecution to prove sanity, for it will be presumed. But if the defendant introduces evidence indicating that he is not sane, the presumption can no longer be relied upon by the State and the prosecution must prove sanity, as it must all other elements of the crime, beyond a reasonable doubt.” [Footnote omitted.] Id. at 16, 268 A.2d at 91.
Mr. Justice Pomeroy agreed with Mr. Justice Bob-bet’s conclusion but made “certain further observations as to the effect of the presumption of sanity and the burdens of proof and production in a case such as this.” Id. at 17, 268 A.2d at 102. It seems fair to summarize his opinion as agreeing with Mr. Justice Jones, *102that a presumption is not evidence, but as disagreeing with Mm, and agreeing with Mr. Justice Roberts, that sanity is an element of the crime. Id. at 19-20, 268 A.2d at 103-04
In the present case the trial judge instructed the jury in accordance with the position adopted by Mr. Justice Jones and Mr. Justice O’Brien in Commonwealth v. Vogel, supra. It would have been error for Mm to have done otherwise, for although Mr. Justice Jones’s opinion was joined only by Mr. Justice O’Brien, it is nevertheless apparent that the dissenting Justices in Yogel, Mr. CMef Justice Bell and Mr. Justice Eagen, agreed with Mr. Justice Jones and Mr. Justice O’Brien in “specifically declin [ing] to adopt the federal rule.”
That this was indeed so was established in Commonwealth v. Zlatovich, 440 Pa. 388, 269 A.2d 469 (1970), where the opinion for the Court was by Mr. Justice Eagen, joined by Mr. Chief Justice Bell, Mr. Justice Jones, and Mr. Justice O’Brien. The facts there were in essence as in the present case: The defendant pleaded not guilty by reason of insanity, and introduced psycMatric testimony in support of the plea; the Commonwealth, “unlike the situation presented in Commonwealth v. Vogel. . . did offer evidence which warranted a finding of sanity . . . .” Id. at 393, 269 A.2d at 471. (It may be noted in passing that in contrast to the present case, tMs evidence did not include any psychiatric testimony but was only by lay witnesses. Id.) Also as in the present case the trial judge instructed the jury that the defendant had the burden of proving insanity by the preponderance of the evidence. In upholding this instruction, Mr. Justice Eagen said: “It is next complained that the trial court erred in its instructions to the jury on the burden of proof as to the issue of insamty. In the course of the charge, the court *103stated, in part, that the accused had the burden of proving insanity by the preponderance of the evidence and that the Commonwealth did not have to affirmatively prove sanity. Appellant argues that it was erroneous to so instruct the jury; however, this same contention was rejected by a majority of this Court in Commonwealth v. Vogel, supra, and nothing would be gained by further discussion here.” Id. at 393, 269 A.2d at 471.
Mr. Justice Cohen concurred in this result; Mr. Justice Roberts dissented, repeating his view, expressed in Commonwealth v. Vogel, supra, that the Commonwealth should be required to prove sanity beyond a reasonable doubt; Mr. Justice Pomeroy also dissented, also repeating the view he had expressed in Vogel, but additionally finding error in the charge “under any of the diverse views expressed by the members of the Court who constituted a majority in Vogel,” id. at 399, 269 A.2d at 474, in that the charge did not malee it clear that the presumption of sanity was not evidence and once rebutted, disappeared.
Since the decision in Commonwealth v. Zlatovich, supra, was filed, the composition of the Supreme Court has changed in that Mr. Chief Justice Bell and Mr. Justice Cohen are no longer members of the Court. In essence, in the present case defense counsel asks us to hold that the trial judge should have charged that the Commonwealth had the burden of proving appellant’s sanity on the assumption that Mr. Justice Nix and Mr. Justice Manderino are of the same view as Mr. Justice Roberts and Mr. Justice Pomeroy. There is, however, no basis for such an assumption; we simply do not know the view of either Mr. Justice Nix or Mr. Justice Manderino, and whether their accession to the court will result in Zlatovich being overruled must abide the event.
*104B.
I believe that the Supreme Court must overrule Zlatovich, if the M’Naghten rule continues to be applied in Pennsylvania.
In concluding that where there is conflicting evidence the defendant should have the burden of proving insanity by the fair preponderance of the evidence, Mr. Justice Jones in Commonwealth v. Vogel, supra, offered two rationales, one based on the M’Naghten rule:
“Inherent in this rule [that the defendant has the burden of proving his insanity] is the rationale that sanity is not an element of the crime but, rather, involves ... a state of mentality which would render punishment by way of confinement in a penal institution futile and would require institutional confinement of the defendant for treatment rather than for punishment .... In my view, insanity is a defense upon the proof of which an accused may avoid punishment for the crime committed ....
“In a jurisdiction which uses the ‘irresistible impulse’ test to determine legal insanity . . . the question of insanity, at the least, is closely connected with the question of whether the killing was intentional. [Footnote omitted.] It may be appropriate, in such a jurisdiction, that the burden of proof as to both should be the same, since they are both concerned with what is clearly an element of the crime — i.e., the intent to kill. In Pennsylvania, a person may be legally insane either if he is incapable of knowing what he was doing, or if he does know what he was doing but was incapable of judging that it was wrong to do so. Commonwealth v. Woodhouse, 401 Pa. 242, 164 A.2d 98 (1960).
“As indicated by the facts in the instant case, legal insanity in this Commonwealth may or may not bear on the question of intent. The prosecution presented ample evidence that Yogel planned his crime, from *105which evidence intention might he inferred, but no evidence that Yogel could appreciate the character of his actions. An individual may intentionally kill someone, with malice aforethought, but be incapable of distinguishing right from wrong in so doing. Under such circumstances, the elements of murder would be met (Commonwealth v. Kirkland, 413 Pa. 48, 195 A.2d 338 (1963)), but the individual’s legal insanity would properly necessitate a verdict of not guilty by reason of insanity. This is the type of situation which is demonstrated on the face of the instant record.” Id. at 10-11, 268 A.2d at 94.
In considering this statement, illustrative paraphrase may be helpful. Suppose X shoots and kills Y because he thinks X is a deadly snake. X would be legally insane under the first part of M’N tighten- because “incapable of knowing what he was doing.” His insanity prevented Mm from forming an intent to kill, such an intent being an element of the crime that X was charged with committing. The burden of proof of essential elements must be on the prosecution. In re Winship, 397 U.S. 358 (1970). Suppose, however, X knew he was killing a man but thought he was acting pursuant to Divine command. He would then be legally insane under the second part of M’N tighten because “incapable of judging that it was wrong [to kill].” Since X knew that Y was a man, and intended to kill Mm, his sanity does not affect proof of an essential element of the crime and the burden may properly be placed on him to prove that he thought that he was acting pursuant to Divine command.*
*106When, in Commonwealth v. Zlatovich, supra at 393, 269 A.2d at 471, the Court held “that the accused had the burden of proving insanity by the preponderance of the evidence and that the Commonwealth did not have to affirmatively prove insanity,” it simply cited Vogel, adding that “nothing would be gained by further discussion here.” This brief statement gives no clue as to whether the majority in Zlatovich agreed with the analysis of Mr. Justice Jones in Vogel, that the rule that the accused has the burden of proof is related to the M’Naghten rule and depends upon what part of that rule the accused is relying upon.
I think that Mr. Justice Jones is correct. Winship and M’Naghten require such uncertainty as to who has the burden; but this result has no logic. If an accused is entitled to be found “not guilty by reason of insanity,” it would seem that the same rules should apply, whatever the nature of the insanity. Why should a person insane because he thought his victim a snake be able to require a stricter standard of proof of the Commonwealth than a person insane because he thought himself an instrument of God? Or to state the issue conversely: Why should a person insane because he has a delusion as to the moral quality of the act he knows he is committing (e.g., he knows he is committing homicide but believes it proper as in accordance with God’s will) stand a poorer chance of acquittal (because he must prove his delusion) than one insane because he has a delusion as to what act he is committing {e.g., he thinks he is killing not a man but a snake, in which case the Commonwealth must prove as an element of the crime that he intended to kill a man) ?
*107I recognize that these questions can be turned around, i.e., why should the Commonwealth have a greater burden in one case than in another? The answer, I suggest, is that there is no reason, any more than there is any reason why the burden should vary for different defendants in different cases. I believe we have been led to this conundrum because of the way in which we have defined insanity.
The Definition of Insanity
In the present case the trial judge in instructing the jury defined insanity in accordance with the M’Naghten rule. This too was in accordance with the most recent decisions of the Supreme Court. Commonwealth v. McCusker, 448 Pa. 382, 292 A.2d 286 (1972) ;* Com*108monwealth v. Woodhouse, 401 Pa. 242, 164 A.2d 98 (1960). However, as the preceding discussion has revealed, as one examines the question of who should have the burden of proving insanity, one is drawn on to the question of how insanity itself should be defined.
I have come to the conclusion that the M’Naghtm rule should be abolished. In coming to this conclusion I have been aided by the recent notable re-examination of the insanity defense in United States v. Brawner, 471 F. 2d 969 (D.C. Cir. 1972).
*109In Brawner the principal issues related to the defendant’s plea of insanity. After the case had been argued to a panel, the court sua sponte ordered rehearing en banc, announcing its “intention to reconsider the appropriate standard for the insanity defense.” Id. at 973. Special counsel was appointed as amicus curiae “ To research the authorities on the issue of criminal responsibility,’ to advise the court thereon and to present oral argument.” Id. In addition, a number of organizations were invited to submit briefs amicus curiae; accepting this invitation were The American Civil Liberties Union Fund of the National Capitol Area, the National Legal Aid and Defender Association, the National District Attorneys Association, the Georgetown Legal Intern Project, the American Psychiatric Association, the American Psychological Association, and the Bar Association of the District of Columbia. From this comprehensive presentation two opinions resulted, one, for the court, by Circuit Judge Leventhal, and a separate opinion by Chief Judge Bazelon.
The difference between the opinions may be summarized by quoting the opening paragraph of The Chief Judge’s opinion: “We are unanimous in our decision today to abandon the formulation of criminal responsibility adopted eighteen years ago in Durham v. United States, 94 U.S. App. D.C. 228, 214 F. 2d 862 (1954). We held there that a person is not responsible for a criminal act if the act was the product of mental disease or mental defect. In place of the Durham jury instruction, juries will now be instructed in terms of the American Law Institute test that a person is not responsible for a criminal act if as a result of mental disease or defect he lacks substantial capacity either to appreciate the wrongfulness of his conduct or to conform his conduct to the requirements of law. But the adoption of this new test is largely an anticlimax, for *110even though Durham’s language survived until today’s decision, the significant differences between our approach and the approach of the Am test vanished many years ago. As described in Judge Leventhai/s scholarly opinion, the Ali test may make possible an improvement in the adjudication of the responsibility issue. But on the whole I fear that the change made by the Court today is primarily one of form rather than of substance.” [Footnote omitted.] Id. at 1010. The Chief Judge stated that he would adopt the following test: “Our instruction to the jury should provide that a defendant is not responsible if at the time of his unlawful conduct his mental or emotional processes or behavior controls were impaired to such an extent that he cannot justly be held responsible for his act. This test would ask the psychiatrist a single question: what is the nature of the impairment of the defendant’s mental and emotional processes and behavior controls? It would leave for the jury the question whether that impairment is sufficient to relieve the defendant of responsibility for the particular act charged.” [Footnote omitted.] Id. at 1032.
It would be an idle display of borrowed learning to undertake to summarize the exchange of reasoning or the authorities collected in the opinions of Circuit Judge Leventi-ial and Chief Judge Bazelon ; one can only express gratitude for them. It is, however, of interest to note that when the issue of criminal responsibility was reexamined by our Supreme Court in Commonwealth v. Woodhouse, supra, Mr. Justice Bok stated in dissent:
“I would abolish the M’Naghten Rule.
“The Rule is not used in any other field where mental competence is at issue. When a commission in lunacy is had or proceedings are taken against a person for the appointment of a guardian, the point of inquiry *111is not whether the patient knows right from wrong but whether he is mentally ill or incapable of handling his property and affairs and is likely to become the victim of designing persons. The Eule does not apply even when the issue is whether he is mentally capable of standing trial and making his defense. The concern of The Mental Health Act of June 12, 1951, P.L. 533, 50 P.S. §1071 et seq., with regard to those accused of crime is with mental health, not with right and wrong. Why should the law’s purpose be different with those convicted of crime?” Id. at 264, 164 A.2d at 109-10. He further stated: “The majority refuses to move against the Rule because no satisfactory alternative to it has been presented. I believe that none is needed....
“If jurors are . . . capable of knowing the difference between right and wrong without being given standards for those terms, they should be equally able, also without given standards, to assess sanity and insanity.” Id. at 266, 164 A.2d at 110-11.
Finally, in a passage that may instructively be compared with the test that Chief Judge Bazeeon would adopt, Mr. Justice Bok stated that he would leave to the jury the task of “decid[ing] whether under all of the circumstances, including [the defendant’s] mental derangement as and if the jury sees it, it would be just to hold [the defendant] accountable: this was the law of England at one period before M’Naghten.” [Citation omitted.] Id. at 266, 164 A.2d at 110.
For my part, I am persuaded by this reasoning and by the considerations advanced by Chief Judge Bazelon in United States v. Brawner, supra.
If this analysis is a correct statement of the views of Mr. Justice Jones, it would seem that the disagreement between Mm and Mr. Justice Bobeets is not so great as might at first appear. Mr. Justice Bobeets, as I understand his opinion in Vogel regards intent as an element of the crime and sanity as a matter of proof for the prosecution in every case in which the defendant’s insanity *106is put in issue, whether it be claimed, under the first part of M’Naghten, that the insanity inheres in the defendant being “incapable of knowing what he was doing” or, under the second part of M’Naghten, in his being “incapable of judging that it was wrong.”
I find I cannot agree either with Judge Jacobs or Judge Hoffman regarding McOnslcer. It does not seem to me that Mc-OusTcer represents an “explicit rejection of the doctrine of diminished responsibility,” as Judge Jacobs suggests, but rather, as Judge Hoffman suggests, announces that doctrine. (See Majority Opinion at 92 with Dissenting Opinion at 120 n.3.) Nevertheless, McCusker seems to me inapplicable to the present case, although I grant that if an appeal is requested and allowed, the Supreme Court might decide to extend it and make it ai>plicable.
McOusker held that in a murder prosecution the defendant could offer psychiatric evidence that he had acted in the heat of passion having its origin in a mental disorder. Proof of such passion would show that the defendant had not acted with malice. Thereby the charge of murder would be reduced to voluntary manslaughter. Perhaps Judge Hoffman is correct that as a matter of logic McOusker should be extended to other than murder cases where the defendant wishes to disprove malice; and it is true that malice was an element of aggravated assault and battery and of assault with intent to maim, as those crimes were defined when appellant was charged and tried. Act of June 24, 1939, P. L. 872, §§709 and 712, 18 P.S. §§4709 and 4712, repealed Act of Dec. 6, 1972, P. L. 1482, No. 334, §5. This issue need not be decided, however, for appellant did not try to disprove malice.
What appellant did try to disprove was intent, and MeOwsTcer simply does not hold that evidence of a mental disorder is admis*108sible on the issue of intent. “Intent” is not the same as “malice,” and evidence pertinent to one may not be pertinent to the other. As noted, in McCuslcer the evidence was offered to show passion. “ ‘Passion, as used in . . . defining manslaughter . . . means any of the emotions of the mind known as anger, rage, sudden resentment or terror, rendering the mind incapable of cool reflection. . . .’ ” Commonwealth v. Colandro, 231 Pa. 343, 350-51, 80 A. 571, 574 (1911). Thus, proof of passion may disprove malice, for “[m]aliee in its legal sense exists . . . where there is a particular ill will, . . . a wickedness of disposition, hardness of heart, wanton conduct, cruelty, recklessness of consequences and a mind regardless of social duty.” Commonwealth v. Bolish, 381 Pa. 500, 510-11, 113 A. 2d 464, 470 (1955). Proof of passion cannot, however, disprove intent.
As I understand Judge Hoffman’s opinion, he would acknowledge that McCuslcer did not involve an offer to disprove intent but he would extend it to include such an offer. Again, he may be correct that such an extension should be made. See Comment, 77 Dick. L. Rev. 435, 440-41 (1972) (“[e]xtension [of McCusker] is warranted because if psychiatric evidence is relevant and probative to determine heat of passion [footnote omitted], the evidence is just as relevant and probative in regard to the specific intent to kill. . . .”). However, so far the Supreme Court has declined to make the extension. Commonwealth v. Ahearn, 421 Pa. 311, 218 A. 2d 561 (1966). Since it is not an extension logically derived from the rationale of McCuslcer but rather is dependent on one’s confidence in psychiatric judgments, whether it should be made ought, in my view, be left to the Supreme Court, and to a case where the defendant has raised the issue with more precision than appellant has here.