18. Section 299 and Section 300 IPC deals with the definition of culpable homicide and murder respectively. Section 299 defines culpable homicide as the act of causing death; (i) with the intention of causing death or (ii) with the intention of causing such bodily injury as is likely to cause death or (iii) with the knowledge that such act is likely to cause death. The bare reading of the section makes it crystal clear that the first and the second clause of the section refer to intention apart from the knowledge and the third clause refers to knowledge alone and not intention. Both the expression "intent" and "knowledge" postulate the existence of a positive mental attitude which is of different degrees. The mental element in culpable homicide i.e. mental attitude towards the consequences of conduct is one of intention and knowledge. If that is caused in any of the aforesaid three circumstances, the offence of culpable homicide is said to have been committed. Section 300 IPC, however, deals with murder although there is no clear definition of murder provided in Section 300 IPC. It has been repeatedly held by this Court that culpable homicide is the genus and murder is species and that all murders are culpable homicide but not vice versa. Section 300 IPC further provides for the exceptions which will constitute culpable homicide not amounting to murder and punishable under Section 304. When and if there is intent and knowledge then the same would be a case of Section 304 Part I and if it is only a case of knowledge and not the intention to cause murder and bodily injury, then the same would be a case of Section 304 Part II. The aforesaid distinction between an act amounting to murder and an act not amounting to murder has been brought out in the numerous decisions of this Court.
19. In the case of State of A.P. v. Rayavarapu Punnayya, (1976) 4 SCC 382, this Court observed as follows at page 386:
"12. In the scheme of the Penal Code, "culpable homicides" is genus and "murder" its specie. All "murder" is "culpable homicide" but not vice-versa. Speaking generally, "culpable homicide" sans "special characteristics of murder", is "culpable homicide not amounting to murder". For the purpose of fixing punishment, proportionate to the gravity of this generic offence, the Code practically recognises three degrees of culpable homicide. The first is, what may be called, "culpable homicide of the first degree". This is the greatest form of culpable homicide, which is defined in Section 300 as "murder". The second may be termed as "culpable homicide of the second degree". This is punishable under the first part of Section 304. Then, there is "culpable homicide of the third degree". This is the lowest type of culpable homicide and the punishment provided for it is, also, the lowest among the punishments provided for the three grades. Culpable homicide of this degree is punishable under the second part of Section 304."
20. Placing strong reliance on the aforesaid decision, this Court in the case of Abdul Waheed Khan v. State of A.P., (2002) 7 SCC 175, observed as follows at page 184:
"13. Clause (b) of Section 299 corresponds with clauses (2) and (3) of Section 300. The distinguishing feature of the mens rea requisite under clause (2) is the knowledge possessed by the offender regarding the particular victim being in such a peculiar condition or state of health that the internal harm caused to him is likely to be fatal, notwithstanding the fact that such harm would not in the ordinary way of nature be sufficient to cause death of a person in normal health or condition. It is noteworthy that the "intention to cause death" is not an essential requirement of clause (2). Only the intention of causing the bodily injury coupled with the offender's knowledge of the likelihood of such injury causing the death of the particular victim, is sufficient to bring the killing within the ambit of this clause. This aspect of clause (2) is borne out by Illustration (b) appended to Section 300.
14. Clause (b) of Section 299 does not postulate any such knowledge on the part of the offender. Instances of cases falling under clause (2) of Section 300 can be where the assailant causes death by a fist-blow intentionally given knowing that the victim is suffering from an enlarged liver, or enlarged spleen or diseased heart and such blow is likely to cause death of that particular person as a result of the rupture of the liver, or spleen or the failure of the heart, as the case may be. If the assailant had no such knowledge about the disease or special frailty of the victim, nor an intention to cause death or bodily injury sufficient in the ordinary course of nature to cause death, the offence will not be murder, even if the injury which caused the death, was intentionally given. In clause (3) of Section 300, instead of the words "likely to cause death" occurring in the corresponding clause (b) of Section 299, the words "sufficient in the ordinary course of nature" have been used. Obviously, the distinction lies between a bodily injury likely to cause death and a bodily injury sufficient in the ordinary course of nature to cause death. The distinction is fine but real and if overlooked, may result in miscarriage of justice. The difference between clause (b) of Section 299 and clause (3) of Section 300 is one of degree of probability of death resulting from the intended bodily injury. To put it more broadly, it is the degree of probability of death which determines whether a culpable homicide is of the gravest, medium or the lowest degree. The word "likely" in clause (b) of Section 299 conveys the sense of probable as distinguished from a mere possibility. The words "bodily injury ... sufficient in the ordinary course of nature to cause death" mean that death will be the "most probable" result of the injury, having regard to the ordinary course of nature.
15. For cases to fall within clause (3), it is not necessary that the offender intended to cause death, so long as the death ensues from the intentional bodily injury or injuries sufficient to cause death in the ordinary course of nature. Rajwant Singh v. State of Kerala is an apt illustration of this point.
16. In Virsa Singh v. State of Punjab Vivian Bose, J. speaking for the Court, explained the meaning and scope of clause (3). It was observed that the prosecution must prove the following facts before it can bring a case under Section 300 "thirdly". First, it must establish quite objectively, that a bodily injury is present; secondly, the nature of the injury must be proved. These are purely objective investigations. Thirdly, it must be proved that there was an intention to inflict that particular injury, that is to say, that it was not accidental or unintentional or that some other kind of injury was intended. Once these three elements are proved to be present, the enquiry proceeds further, and fourthly, it must be proved that the injury of the type just described made up of the three elements set out above was sufficient to cause death in the ordinary course of nature. This part of the enquiry is purely objective and inferential and has nothing to do with the intention of the offender.
17. The ingredients of clause "thirdly" of Section 300 IPC were brought out by the illustrious Judge in his terse language as follows: (AIR p. 467, para 12) "12. To put it shortly, the prosecution must prove the following facts before it can bring a case under Section 300 `thirdly'; First, it must establish, quite objectively, that a bodily injury is present; Secondly, the nature of the injury must be proved; These are purely objective investigations. Thirdly, it must be proved that there was an intention to inflict that particular bodily injury, that is to say, that it was not accidental or unintentional, or that some other kind of injury was intended. Once these three elements are proved to be present, the enquiry proceeds further and, Fourthly, it must be proved that the injury of the type just described made up of the three elements set out above is sufficient to cause death in the ordinary course of nature. This part of the enquiry is purely objective and inferential and has nothing to do with the intention of the offender."
18. The learned Judge explained the third ingredient in the following words (at p. 468): (AIR para 16) "The question is not whether the prisoner intended to inflict a serious injury or a trivial one but whether he intended to inflict the injury that is proved to be present. If he can show that he did not, or if the totality of the circumstances justify such an inference, then, of course, the intent that the section requires is not proved. But if there is nothing beyond the injury and the fact that the appellant inflicted it, the only possible inference is that he intended to inflict it. Whether he knew of its seriousness, or intended serious consequences, is neither here nor there. The question, so far as the intention is concerned, is not whether he intended to kill, or to inflict an injury of a particular degree of seriousness, but whether he intended to inflict the injury in question; and once the existence of the injury is proved the intention to cause it will be presumed unless the evidence or the circumstances warrant an opposite conclusion."
19. These observations of Vivian Bose, J. have become locus classicus. The test laid down by Virsa Singh case for the applicability of clause "thirdly" is now ingrained in our legal system and has become part of the rule of law. Under clause thirdly of Section 300 IPC, culpable homicide is murder, if both the following conditions are satisfied i.e. (a) that the act which causes death is done with the intention of causing death or is one with the intention of causing a bodily injury; and (b) that the injury intended to be inflicted is sufficient in the ordinary course of nature to cause death. It must be proved that there was an intention to inflict that particular bodily injury which, in the ordinary course of nature, was sufficient to cause death viz. that the injury found to be present was the injury that was intended to be inflicted.
20. Thus, according to the rule laid down in Virsa Singh case even if the intention of the accused was limited to the infliction of a bodily injury sufficient to cause death in the ordinary course of nature, and did not extend to the intention of causing death, the offence would be murder. Illustration (c) appended to Section 300 clearly brings out this point.
21. Clause (c) of Section 299 and clause (4) of Section 300 both require knowledge of the probability of the act causing death. It is not necessary for the purpose of this case to dilate much on the distinction between these corresponding clauses. It will be sufficient to say that clause (4) of Section 300 would be applicable where the knowledge of the offender as to the probability of death of a person or persons in general as distinguished from a particular person or persons -- being caused from his imminently dangerous act, approximates to a practical certainty. Such knowledge on the part of the offender must be of the highest degree of probability, the act having been committed by the offender without any excuse for incurring the risk of causing death or such injury as aforesaid.
22. The above are only broad guidelines and not cast-iron imperatives. In most cases, their observance will facilitate the task of the court. But sometimes the facts are so intertwined and the second and the third stages so telescoped into each, that it may not be convenient to give a separate treatment to the matters involved in the second and third stages."
21. The aforesaid principles have been consistently applied by this Court in several decisions. Reference in this regard may be made to the decision of this Court in Ruli Ram v. State of Haryana, (2002) 7 SCC 691; Augustine Saldanha v. State of Karnataka, (2003) 10 SCC 472; State of U. P. v. Virendra Prasad, (2004) 9 SCC 37; Chacko v. State of Kerala, (2004) 12 SCC 269; and S. N. Bhadolkar v. State of Maharasthra, (2005) 9 SCC 71.