I think it just depends on how you read the text. I could make an argument to you either way. And I will.
Firstly, I think Macbeth shows real wavering doubts about doing the murder. He says, just after he receives the news that he's just going to leave it up to the fates, and let what happens happen:
If chance will have me king, why, chance may crown me
Without my stir. Come what come may,
Time and the hour runs through the roughest day.
So that's evidence that he's not going to do it. And then later in Act 1, Scene 7, he talks himself right out of it, even telling Lady M
We will proceed no further in this business:
He hath honor'd me of late, and I have bought
Golden opinions from all sorts of people,
Which would be worn now in their newest gloss,
Not cast aside so soon.
She persuades him around. But before that, it looks very much like he isn't going to do it. And why would he? If the prophecies are true, they'd happen no matter what he did.
On the other hand, Macbeth admits very quickly after the prophecies that he has "black and deep desires" for the throne, for power, and to become king. It's clearly been going on long before the prophecies were made by the witches:
Stars, hide your fires;
Let not light see my black and deep desires:
The eye wink at the hand; yet let that be
Which the eye fears, when it is done, to see.
Macbeth is undoubtedly ambitious. And, in the end, he does the deed and murders Duncan. Surely he wouldn't murder someone simply because his wife said so? Or would he?
It's one of those questions. You can't imagine him without his wife, really - you can't imagine what he'd be like. So you can argue it both ways.
Hope it helps!
It's also interesting to look at the physical evidence. Shakespeare's plays contain very few stage directions, but there are often clues in the dialogue. For example, when the witches prophesy that Macbeth shall be 'king hereafter', Banquo asks - 'Why do you start?' So we can assume that the witches have touched a nerve.
Of course, it's equally possible that the words of the witches remind Macbeth of his wife's nagging. We know the couple have discussed murder in the past; Lady Macbeth tells us that her husband had agreed to the crime even when fate had not delivered Duncan to their castle: 'Nor time nor place did then adhere, and yet you would make both'.
On the other hand Macbeth does have a decent, honourable streak, remembering Duncan's kindness to him and rejecting 'vaulting ambition'. However, this phrase is Lady Macbeth's cue - she IS his ambition, and she is the ultimate persuader, using scorn and emotional blackmail to win him over.
It's also interesting that Macbeth never reproaches Lady Macbeth after the murder, and even tries to protect her from further involvement - 'Be innocent of the knowledge, dearest chuck'. He becomes more ruthless than she does, although both are horribly punished by dreams and mental breakdown.
As this is a 'Do you think...' question, both sides of the argument are required. There's no straightforward answer, and no critics who blame Lady Macbeth 100%. Of course, it's possible to play her as another victim of the witches, even though she never meets them...
most definately not, i believe he was in doubt and if it weren't for his wife, he would not have murdered Duncan, she was pushy and concieted. "consider it not so deeply"
this film is one of the greatest classics of all time, i was emotional in parts.
i watch it every 4th December because that's when i first saw it, such a brilliant film, well done Shakespeare, one of the greats.