greater excesses of brutality. In that sense, the murder of Duncan actually marks the beginning of a greater slide into wickedness. Thus, more than anyone else in the play, primary responsibility for his downfall rests with Macbeth himself.

In Shakespeare's Macbeth, Lady Macbeth is partly to blame for Macbeth's downfall. 

• They both react to the predictions that Macbeth will be king in the same way, even though separated:  they both instantly jump to the conclusion that killing Duncan is what will be necessary for the prediction to be fulfilled. 
• When they do meet, they suggest in their conversation that they should assassinate Duncan that night while he is sleeping in their castle.  Macbeth is still deciding, but Lady Macbeth is already certain.
• Macbeth decides not to kill Duncan, but Lady Macbeth talks him into it by using manipulation and questioning his manhood.
• But when Lady Macbeth has an opportunity to kill Duncan herself, she cannot go through with it.
• Macbeth can, and does, kill Duncan himself.
• Lady Macbeth just does a lot of talking and planning, but Macbeth does the killing.  Furthermore, Lady Macbeth has nothing to do with the rest of the killings that occur--those are all Macbeth.  She is shocked when he kills the grooms, and is unaware when he orders the killings of Banquo and Macduff's family.

Ironically, if Lady Macbeth would have had more to do with the later killings, Macbeth might have gotten away with them.  It is only when Macbeth varies from his wife's plans or acts without her knowledge that he makes mistakes and creates suspicion.

Ultimately, I do not think you can give Lady Macbeth all the blame for her husband's downfall.  I think she helped him along, but it is clearly his own responsibility as well.

Macbeth's ambition is not awakened by anything his wife does.  Instead, it is awakened by what the witches tell him.  So he is already ambitious before we even see Lady Macbeth.

In addition, Lady Macbeth does not force Macbeth to do anything.  True, she pushes him towards doing evil, but he is the one who ultimately decides and he does not seem to resist very hard either.

Lady Macbeth is a schemer. In act 1, scene 5, she begins making serious plots against Duncan's life:

And that which rather thou dost fear to do,Than wishest should be undone. Hie thee hither,That I may pour my spirits in thine earAnd chastise with the valor of my tongueAll that impedes thee from the golden round,Which fate and metaphysical aid doth seemTo have thee crowned withal.

She lacks the courage to murder him herself, so she relies on influencing Macbeth to commit the murder instead. She asks that her own soul be blocked from any feelings of regret over the deed and calls for "murd'ring ministers" to assist her evil thoughts.

Lady Macbeth coaches her husband in how to best deceive Duncan. When he wavers in his resolution, Lady Macbeth responds by insulting his masculinity. She pushes him relentlessly in this speech until he returns to agreeing with her plans.

Ultimately, Lady Macbeth is definitely somewhat to blame in the conspiracy. Without Lady Macbeth, it is unlikely that Macbeth would have carried out such plans. But is she to blame for the actual murder and death? I would argue no. Ultimately, Macbeth makes his own choices. He succumbs to the will of his wife, who is unable to follow through with her evil plans herself. Although his dissent would have made his wife unhappy, Macbeth still had that option. Instead, he chooses murder and believes in the seemingly self-fulfilling prophesies of the witches. Although it is likely he would not have carried through with the plans without his wife's influence, Macbeth is ultimately to blame for the actual murder—not Lady Macbeth.

There are many aspects of Lady Macbeth’s behavior that contribute to her husband’s decision to kill the king, but ultimately she is not to blame. Although she conspires with Macbeth, to place the blame on her would be to exonerate the person who committed the murder. Macbeth had free will and made a conscious decision to commit homicide—and regicide, the treasonous act of killing the king. He could have pulled out at any time, but he went ahead with the plan.

Another person assigning blame to her, however, is distinct from her blaming herself for her role. One of the most interesting tactics that William Shakespeare employs is to contrast her lack of physical involvement with her obsession over the deed. She literally has no blood on her hands, but her guilt leads to the figurative blood on her hands. In her conscious, waking hours, she knows she did not participate in the stabbing, but in her sleep, she imagines the “damned spot” that she cannot wash away.

Lady Macbeth is certainly responsible for King Duncan's assassination and not only masterminds the plot to kill him but also participates in the murder by helping her husband conceal his involvement. After receiving news of the witches' favorable prophesies, Lady Macbeth reveals her ambitious nature by commanding evil spirits to assist her murderous thoughts and fill her with cruelty. She then persuades her reluctant husband to commit the murder by ridiculing his masculinity and assuring him that they will get away with the crime. Lady Macbeth then masterminds the plot to kill King Duncan. She participates in the murder by drugging his chamberlains and placing the bloody knives back into the king's room following the assassination. While Macbeth is directly responsible for murdering the king, it is Lady Macbeth who convinces him to act upon his ambition and develops the murderous scheme. In addition to persuading her husband, Lady Macbeth contributes to the crime and assures that Macbeth usurps power with relative ease. One could argue that if it were not for Lady Macbeth's influence and help, her husband would not have carried out the heinous crime.

Lady Macbeth bears a large share of responsibility for King Duncan's murder. It is she who meticulously plans the foul deed and its subsequent cover-up down to the last detail; it is she who constantly encourages, incites, and cajoles her husband into committing this most heinous of crimes. In particular, she plays upon Macbeth's reputation as a brave, fearless warrior, to get him to do what she wants. She cunningly impugns his virility when he appears to get cold feet about killing Duncan; and the last thing a valiant soldier like Macbeth wants is to be thought of as a wimp and a coward by anyone, least of all his own wife. Macbeth's head has already been turned, the seeds of ambition planted in his mind by the Weird Sisters' prophecy. But, it takes the active encouragement of Lady Macbeth to fertilize the soil, so to speak, to turn her husband's overweening ambition into action.

Lady Macbeth is an accessory to murder, but she is not the murderer, and cannot, therefore, be more culpable than Macbeth, who did the deed with his own hand. That she is an accessory goes without argument: it was she who drugged the guards and who laid the daggers out in readiness; it was she, also, who rang the bell to alert Macbeth that the preparations had been made.

But she was no murderer. As evil as Lady Macbeth is, she couldn't actually bring herself to commit the act (she said she might have done it, had Duncan not looked like her father as he was sleeping). So the Lady is all talk, no action.

Where people would argue that her culpability lies is in her talk. She is brutal in her manipulation of Macbeth, drawing on every possible strategy available to woman. The argument for finding Lady Macbeth blameworthy hinges on the fact that her "motivational speech" changes Macbeth's mind. Completely.

Just prior to this speech, Macbeth has decided that he has no good reason to kill Duncan (he hasn't), and he has just informed her of his decision to "proceed no further". She responds to this by saying that if he can lose his ambition so readily, his love for her must also changable. Then she insults his masculinity, saying he must be a coward (afeard to be the same in thine own act as in thine desire). He tries to tell her that he dares all that a man should dare, to which she replies that only if he dared to do it would he be one. At each stage in her argument, she increases the brutality of her verbal attack until (my favorite) she says if she had made a promise to her husband like the one he made to her she would rather rip her baby's smiling face from her nipple and bash its brains out than break that promise. At which point, he's right back in the game. So her words do definitely move him back to murder.

But is she guilty of murder? I would argue no. Macbeth has a mind. He simply doesn't use it. He follows Lady Macbeth's direction, certainly, but has he no choice? I would argue that he does, that as powerful as her emotional argument is, that Macbeth has always had free will and has made his decision (albeit a bad one). The fact that Macbeth seems to perpetually follow bad advice does not make him any less responsible for his actions.

Of course, others would argue that Lady Macbeth's manipulation is so complete that he has no choice, that the threat of spending a night, nay, a lifetime on the couch is simply too much for a man to bear.

One of Lady Macbeth's most famous quotes in Macbeth is "the milk of human kindness." With this quote she is describing Macbeth who she thinks will never be King because he isn't strong willed enough to do what Lady Macbeth believes needs to be done. Compassion (according to Lady Macbeth) isn't something that should be lauded, but instead is something to be scorned. Because of this attitude of hers, she decides that she must be the driving force behind her husbands rise to the throne. She, therefore, convinces and plots and schemes to get her husband to kill Dincan

Most scholars believe that Lady Macbeth kills herself, as Malcolm's closing speech in Act 5, Scene 8 suggests this fact: "...his fiend-like queen, / Who, as 'tis thought, by self and violent hands / Took off her life" (69-71). Using this speech as their guide, most scholars hypothesize that Lady Macbeth was not killed by a person, but committed suicide. This idea logically follows from Lady Macbeth's increasingly maddened actions: as the play goes on, Shakespeare shows us a queen driven mad by her vile crimes. As such, it's possible to assume that, crazy with grief and guilt, Lady Macbeth commits suicide in the final scenes of the play. 

That said, Shakespeare loves to employ ambiguity in his dramatic work, and so it's fitting that a great deal of ambiguity surrounds the death of Lady Macbeth. She dies offstage, and so we don't know for sure exactly how she dies. Malcolm merely reports a very plausible rumor concerning her death, but he does not know the truth for sure. As such, it's theoretically possible (although not overtly supported within the text itself) that Lady Macbeth was killed, potentially by a member of the court who resented the queen's evil actions. Though it's much more likely that Malcolm's theory is correct, the ambiguous nature of Lady Macbeth's death allows for the possibility of foul play.