Why did the Macrobes demand another head at the end of That Hideous Strength?

Question

Towards the end of the book, following Merlin bringing about the destruction of much of the N.I.C.E., Dr. Filostrato, John Withers, and Reverend Straik go to see the Head. The Macrobes promptly demand another head; Withers and Straik promptly kill Filostrato in order to supply it with one. Eventually, they realize that the Head will just demand another Head, and they promptly turn on each other.

That being said, why did the Macrobes make this demand? Why the gratuitous killing of people that were working for them?

Answer 1

The macrobes used a human head as an instrument of physical communication with their human pawns. We know that they can communicate with humans without the head, but that tends to scare the daylights out of their pawns, so the head is a useful charade. With the original head destroyed or out of commission, the macros needed another--mostly for their own convenience in communicating, and centering their pawns' loyalty around something vaguely human.

But I think Lewis may also have been making a larger, more metaphorical point here. Evil spirits have always used humans as pawns. In fact they can't accomplish much without them. The macrobes need the cooperation of humans to maximize their nefarious results. They also care nothing for "the head" or anyone else, as soon as that person has served his purpose and is no longer of value. The macrobes truly use people in the worst sense of the word. This is in sharp contrast with the good guys. Ransom and his "spirits" also, in a sense, use people. But those people are not discarded and abandoned to destruction as soon they have served their purpose. The opposite occurs: those who have been "used" are elevated, empowered, preserved, and blessed.

To make an even larger point, there are numerous remarkable similarities and contrasts between Belbury and St. Anne's.

Consider first the similarities:

1. They both have people and those people do work.
2. They both have headquarters at a physical location.
3. They both have a "head" that is clearly in charge.
4. They are both at odds with the "other side". They are enemies, literally and figuratively.
5. They are both secretive, but the reasons for the secrecy are quite different for each side.
6. Both societies have a head that is governed by spirits from another realm.

Now consider their differences:

1. St. Anne's consists of flawed but nice people; Belbury consists of very nasty NICE people!
2. Belbury obtains and controls its followers using greed, threats, fear, seduction, and promises of power. Ransom obtains and influences his followers using love, respect, and protection.
3. Belbury desires power and dominion. St. Anne's desires life and righteousness.

My point regarding the similarities and contrasts is that Belbury turns on itself and cannibalizes itself -- symbolized by the demand for another head and the murders that follow. While St. Anne's comes out better, stronger, and safe at the end!

Answer 2

Short answer: Because the macrobes didn't care about people, not the people at N.I.C.E. or anywhere else, they only cared about their own designs and ends.

I would add to the first (earliest) answer, that the scene that closes the narrative to the reader on N.I.C.E. does, and likely is intended to, resemble one of the most historically denigrating things in humanity (in the context of Western Reformation thought, at any rate); primitive tribal totem worship. What Lewis portrays is the pinnacle of 'human achievement' coming up through the top of intellection and emerging back out of the bottom in bleak savagery. Whether it was intentional or conscious on Lewis' part or not, it is a coarse depiction of Nietzschean philosophy (recall that Nietzsche himself was committed to a sanitorium), a sort of intellectual Ouroboros where the desire to 'improve on' humanity ends up dehumanizing it completely.

Literarily, there is an underpinning for this in Lewis' nonfiction work "The Abolition of Man," in which Lewis explicitly declares it to be about formal education and morality. In speculating about the group he labels "The Conditioners", he states that

I think they would be inclined to hate the conditioned, for they still enjoy the comforts of an 'illusionary' morality from which they have freed themselves in order to direct their fate

(from memory, not an exact quote). Here, as the earlier answer elucidates, 'The Conditioners' would be the macrobes, and the conditioned their acolytes within N.I.C.E., ultimately to be the people of Great Britain. So for the conditioners, their designs having been frustrated by the sane and sanguine 'spirits' opposing them, would have no reason to not vent their frustrations upon creatures they treated as mere tools (rather than allies or valued servants as with St. Annes, as the earlier answer astutely points out). Lewis being a Christian at this point, one might connect this observation to the several New Testament parables using servants as characters and/or object lessons.

Historically, he was one of many post-facto witnesses to the inhumane brutalities perpetrated by the NAZI party and the Third Reich on greater Europe, and having been a veteran of WWI, was sufficiently composed and qualified to actually contemplate and analyze it in a sort of 'intellectual autopsy', if you will. Lewis has also commented on this among his essays, one in particular where he coined the term "bulverism" out of his own personal experience and 'headcanon', if you will. He conveyed at one point in "The Screwtape Letters" Ch. I, I believe, that in his conception there were higher powers hostile to humanity, which wanted to enfeeble rather than enhance human intellect, penning

...that nonsense in the intellect should reinforce corruption in the will.

Elsewhere (I believe in Mere Christianity, pt. 4), he comments on the progressive inhumaneness of NAZI perspective and conduct, saying something close to

In the beginning, the NAZIs mistreated the Jews because they hated them; towards the end, they hated them because they had mistreated them.

So, in a sense, the Macrobes turn out to be as sinisters as, or even more so than, amoral deceptive aliens who are only using humans as a means to other ends (this is a major plot element of the Sci-Fi TV series "Earth: Final Conflict", directed by William Shatner and novelized if I am not mistaken), and only value them insofar as they are useful towards those ends. Recall that elsewhere in the novel and the Space Trilogy, Earth (Thulcandra) is portrayed as a world under a sort of seige, and the powers collected there are striving against an immensely superior power, the way that Jerusalem strove against Babylon or Carthage sought to rival Rome. So there is a sense in which the Macrobes are intensely desperate to make any kind of progress, and setbacks might be treated with a sort of supernatural manic response as the scene portrays. To stay within literary canon, juxtapose what happened with Devine et al. and 'the head' at N.I.C.E., with what happened with Weston on Perelandra in the same-titled book; treat Weston as a living subject for the Macrobes (the human name for them, in "Out of the Silent Planet" they end up being called the " 'bent' eldil") and you will get a better perspective on their motivations and methods.

The parallels to tribal totem worship, while apparent to me in the scene, are better treated by someone whose specialty is anthropology, not philosophy or literature.