I’m going to talk about corrupting sorcery here, I suppose. I really don’t want to use terms like black magic or nigromancy or anything like that because there’s too much uncritical cultural baggage there. And I’m going to get at this through the Scottish Play.
In Macbeth, the play mediates and frames how we experience Macbeth. We hear about him before we see him, and what we hear about him is that he’s a badass. He and his pal Banquo are fighting as thanes for King Duncan, and they’re fighting dastardly rebels. They’re in a bad place during a battle, but Macbeth doesn’t give a shit. His sword is smoking with the warm blood of his foes, and he sees the rebel leader, “carves” his way through the battlefield, and without pleasantries cuts the guy open from the “nave to the chops” and takes his head. The first report of Macbeth we have is of his brutal and efficient violence on behalf of his lawful sovereign, and Duncan is fucking overjoyed at his loyal thane.
Now, the play opens with the Weird Sisters appearing onstage and scheming in rhyming couplets. And we see them again before we see Macbeth for the first time. The play shows us they’re not radical witches: they are petty, vindictive beings, willing to curse a sailor and his ship to drown because the sailor’s wife wouldn’t share her chestnuts. Before Macbeth arrives, they weave their charm in anticipation of seeing him:
The weird sisters, hand in hand,
Posters of the sea and land,
Thus do go about, about:
Thrice to thine and thrice to mine
And thrice again, to make up nine.
Peace! the charm’s wound up.
Macbeth and Banquo then appear onstage, and Macbeth utters his first line of the play: “So foul and fair a day I have not seen.” He hasn’t noticed the Witches yet. At this point, Macbeth is as much any other character we might encounter in Shakespeare, and he talks about the weather. Even Banquo’s initial comment is mundane: “How far is’t call’d to Forres?” But then they see the Witches, and Banquo and Macbeth are shocked and confused, practically traumatized by their appearance. They are uncanny and supernatural-seeming, and Macbeth asks them to speak, “if [they] can,” and he asks, “what are you?”
The Witches immediately hail Macbeth by his current title (Thane of Glamis), the title he’s about to be awarded by Duncan (Thane of Cawdor), and the title they prophesy (king). And these proclamations blow Macbeth’s mind (“Good sir,” Banquo asks him, “why do you start”?).
The Witches have delivered their woven words against Macbeth, using the almost immediately confirmed truth of his new title (Thane of Cawdor) to make the third title seem more plausible. But all the Witches do is talk to Macbeth. They plant the idea of being king in Macbeth’s mind, and he begins wondering how do I become king. He spreads that idea to Lady Macbeth through the letter he sends her, and the words and idea spreads to her.
When we see the Witches again later, Macbeth has become king, having murdered Duncan in his sleep, having murdered Duncan’s framed guards, and having arranged the murder of Banquo (and the attempted murder of Banquo’s son). And the Witches and the play’s version of Hecate make it plain that they want to mislead Macbeth, to cause more strife, to help bring about his downfall as “black Macbeth.” Hecate chides her Witches, reminding them that they have spurred Macbeth to become king, but he
Loves for his own ends, not for you.
But make amends now: get you gone,
… thither he
Will come to know his destiny:
Your vessels and your spells provide,
Your charms and every thing beside.
And that distill’d by magic sleights
Shall raise such artificial sprites
As by the strength of their illusion
Shall draw him on to his confusion:
He shall spurn fate, scorn death, and bear
He hopes ‘bove wisdom, grace and fear:
And you all know, security
Is mortals’ chiefest enemy.
That is, Hecate tells them to prepare a show for Macbeth’s benefit, to “draw him on to his confusion” through “magic sleights” through “artificial” spirits and their “illusion.” Put another way, they put on a show, a spectacle, a fiction for Macbeth. They weave a story for him, to egg him on to his doom and to cause more mayhem and mischief.
Now, folks like to accuse magic of being nothing more than illusion and lies, but illusion and lies can certainly accomplish much, especially when it comes to the politics of the state, in spurring and moving the ambitious and the fearful and the angry. And Shakespeare and his fellows (Marlowe, Middleton, in particular) recognized the theatricality of public life (Machiavelli hammers that home in The Prince) and the theatricality of magic (ahem, see this play, The Tempest, Doctor Faustus, Midsummer Night’s Dream, the Puritan screeds against theater, the Protestant Reformation, Giordano Bruno, and Giulio Camillo).
My point is that the Witches use theater and words and ideas to destroy the Scottish state, ushering in a tyrant who indulges in excessive cruelty to try to safeguard his power. This cruelty moves the populace from fear and into hatred against Macbeth, culminating in his equally violent death and beheading by Macduff and the accession of King Malcolm, one of Duncan’s sons.
Here’s another thing, though. Malcolm isn’t the “good king.” When he learns his dad has been murdered and the thanes (including Macbeth) are bewailing the regicide and moaning, Malcolm doesn’t join in. He’s rather pragmatic: “O, by whom?” he asks when he’s told Duncan has been murdered. He and his brother Donalbain immediately flee Scotland to England and Ireland respectively. While in England, he meets up with the expatriate Macduff. And he tests Macduff, worried he’s one of Macbeth’s agents. He tells Macduff that, sure,
I grant him bloody,
Luxurious, avaricious, false, deceitful,
Sudden, malicious, smacking of every sin
That has a name: but there’s no bottom, none,
In my voluptuousness
Sure, he tells Macduff, Macbeth is a vicious, bloody tyrant, but Malcolm admits to a willingness—an eagerness—to essentially rape every woman in Scotland, to steal the property of every noble in Scotland and to stir up strife so he can claim more. Macduff seems stricken by these vices, but he tries to put a spin on Malcolm’s treachery. Finally, though, Malcolm admits to having no redeeming qualities:
But I have none: the king-becoming graces,
As justice, verity, temperance, stableness,
Bounty, perseverance, mercy, lowliness,
Devotion, patience, courage, fortitude,
I have no relish of them, but abound
In the division of each several crime,
Acting it many ways. Nay, had I power, I should
Pour the sweet milk of concord into hell,
Uproar the universal peace, confound
All unity on earth.
Macduff at this point can only moan out “O Scotland, Scotland.” Now, Malcolm is testing Macduff, he reassures him in the end, but Malcolm demonstrates in his appearances in the play that he’s a Machiavellian. He understands that he must seem virtuous rather than actually being virtuous. And with Macduff, he stages his own bit of theater—just testing!—but he can imagine being worse than Macbeth, and Macbeth is where he is now because he was helped to imagine being king. Macbeth is a piss-poor Machiavellian prince: however, Malcolm shows every sign he’ll be quite effective in the theater of sovereign authority.
So, in a way, Malcolm is also just as much a weaver as the Witches. Even Lady Macbeth conjures up her own hardened heart:
Come, you spirits
That tend on mortal thoughts, unsex me here,
And fill me from the crown to the toe top-full
Of direst cruelty! make thick my blood;
Stop up the access and passage to remorse,
That no compunctious visitings of nature
Shake my fell purpose, nor keep peace between
The effect and it! Come to my woman’s breasts,
And take my milk for gall, you murdering ministers,
Wherever in your sightless substances
You wait on nature’s mischief! Come, thick night,
And pall thee in the dunnest smoke of hell,
That my keen knife see not the wound it makes,
Nor heaven peep through the blanket of the dark,
To cry ‘Hold, hold!’
So, really, as Constantine told Alan Moore, “Any[one] could do [magic].” Everyone is doing magic. Everyone’s doing political magic. And even the people you wouldn’t expect to be malefic magicians in their suits and tweets and Facebook shares are achieving disasters and foul-fairs. It’s only when it’s too late that Macbeth realizes how he’s been manipulated through “the equivocation of the fiend / That lies like truth,” and he refuses to imagine another way or to step away or to repent/redeem himself because of his pride—despite the fact that since the night he murdered Duncan to gain the throne, he hasn’t slept, he’s been haunted by his conscience (i.e., Banquo’s ghost), and longs for oblivion and annihilation than continued life.
And my point here isn’t that Shakespeare’s saying “Ooo magic is bad!” He’s saying that, if you aren’t the one weaving and shaping your reality—scripting and staging your reality—and if you aren’t looking out for others trying to do so to you, then someone is going to do so to you. Better to be an actor, playwright, magician, witch, and Machiavellian and navigate your way through the world and Otherworlds.
 Yeah, you probably see what I did there. Also, that’s just the first link I found for Moore’s Constantine account.