"Meg, don't get mad, but do you think maybe they don't know?"
A slow tear trickled down Meg's cheek. "That's what I'm afraid of." (3.165-166)
It sounds like Meg could stand not knowing what's going on with her dad, so long as she's sure someone does know. This is similar to how when Meg does finally meet up with her father, she's fine not saving the world herself, so long as she believes he's going to do it. What's terrifying is knowing that even the people who are supposedly in charge don't have a clue.
Meg looked. The dark shadow was still there. It had not lessened or dispersed with the coming of night. And where the shadow was the stars were not visible.
What could there be about a shadow that was so terrible that she knew that there had never been before or ever would be again, anything that would chill her with a fear that was beyond shuddering, beyond crying or screaming, beyond the possibility of comfort? (4.130-131)
The impact of the Black Thing seems to be beyond logic – Meg doesn't yet have any reason to fear it, but she sill does.
[Mrs. Whatsit] " That's another reason we wanted to prepare you on Uriel. We thought it would be too frightening for you to see it first of all about your own, beloved world." (5.107)
Pure evil is one thing, but pure evil visiting you at home is even worse. It's like the difference between a scary movie about kids going to visit a haunted house vs. one about kids whose own house turns out to be haunted – the latter is more terrifying, because it feels like nowhere, not even home, is safe.
"It's all right," Meg assured the Medium earnestly. "Truly it is, Mrs. Medium, and we thank you very much."
"Are you sure?" the Medium asked, brightening.
"Of course! It really helped ever so much because it made me mad, and when I'm mad I don't have room to be scared." (6.54-56)
What is it about anger that drives away fear? Is it just that, as Meg suggests, she only has room for one strong emotion at the time? Or is there something in the feeling of outrage that counteracts fright?
Charles Wallace looked steadily at Mrs. Whatsit. "Are you afraid for us?"
"But if you weren't afraid to do what you did when you were a star, why should you be afraid for us now?"
"But I was afraid," Mrs. Whatsit said gently. (6.79-82)
This conversation reveals a blind spot in Charles Wallace – he seems to think that if you do something brave, it means that you're not scared, whereas Mrs. Whatsit explains that bravery and fear can go hand-in-hand. This suggests a more complicated view of heroism: perhaps the real hero is not the person (or star) who does something without fear, but the one who is scared but does it anyway.
Then the voice was directed to Meg. "To you I leave my glasses, little blind-as-a-bat - But do not use them except as a last resort. Save them for the final moment of peril." As she spoke there was another shimmer of spectacles, and then it was gone, and the voice faded out with it. The spectacles were in Meg's hand. She put them carefully into the breast pocket of her blazer, and the knowledge that they were there somehow made her a little less afraid. (6.89)
While the promised usefulness of the glasses might give Meg a sense of security, it may also be that just having a little piece of Mrs. Who makes her feel better, regardless of the power it might have against her enemies. Previously, Meg has felt better in scary situations when she had a sense that the people around her cared about her.
At the tone of Mrs. Whatsit's voice, both warning and frightening, Meg shivered again. And Charles Wallace butted up against Mrs. Whatsit in the way he often did with his mother, whispering, "Now I think I know what you meant about being afraid."
"Only a fool is not afraid," Mrs. Whatsit told him. "Now go." And where she had been there was only sky and grasses and a small rock. (6.96-97)
According to Mrs. Whatsit, fear is a sign of intelligence. This is in part due to having enough of a clue to recognize the danger in the situation, but it might be something more – how might being scared lead to a person making smarter choices?
"No," Charles Wallace said. "I have to go on. We have to make decisions, and we can't make them if they're based on fear." (7.48)
This seems almost the reverse of the previous quote. While Mrs. Whatsit seems to be saying to listen to their fears, or at least be aware of them, Charles Wallace wants to set them aside altogether. Which is right? Is either?
Meg was so sick and dizzy from the impact that she could not answer. For a moment she was afraid that she would throw up or faint. Charles Wallace laughed again, the laugh that was not his own, and it was this that saved her, for once more anger overcame her pain and fear. Charles Wallace, her own real, dear Charles Wallace, never laughed at her when she hurt herself. Instead, his arms would go quickly around her neck and he would press his soft cheek against hers in loving comfort. But the demon Charles Wallace snickered. She turned away from him and looked again at the man in the column. (9.3)
Perhaps anger counters fear because it directs emotions outward? Instead of being scared about what's going to happen to you, you instead think about what you would like to do to the person you are mad at...
"Put your arms around my neck, Meg," Mr. Murry said. "Hold on to me tightly. Close your eyes and don't be afraid." He picked her up and she wrapped her long legs around his waist and clung to his neck. With Mrs. Who's spectacles on she had felt only a faint darkness and coldness as she moved through the column. Without the glasses she felt the same awful clamminess she had felt when they tessered through the outer darkness of Camazotz. Whatever the Black Thing was to which Camazotz had submitted, it was within as well as without the planet. For a moment it seemed that the chill darkness would tear her from her father's arms. She tried to scream, but within that icy horror no sound was possible. Her father's arms tightened about her, and she clung to his neck in a strangle hold, but she was no longer lost in panic. She knew that if her father could not get her through the wall he would stay with her rather than leave her; she knew that she was safe as long as she was in his arms. (9.62)
Meg seems very childlike at this moment, in her absolute trust that her father is going to make everything all right, and that there's nothing to be scared of so long as he is there. She also seems not to be thinking very clearly – she may be "safe" trapped in the column with her father, but that's hardly a good place to be.
She felt that she was beyond fear now. Charles Wallace was no longer Charles Wallace. Her father had been found but he had not made everything all right. Instead everything was worse than ever, and her adored father was bearded and thin and white and not omnipotent after all. No matter what happened next, things could be no more terrible or frightening than they already were.
Oh, couldn't they?
As she continued to step slowly forward, at last she realized what the Thing on the dais was.
IT was a brain.
A disembodied brain. An oversized brain, just enough larger than normal to be completely revolting and terrifying. A living brain. A brain that pulsed and quivered, that seized and commanded. No wonder the brain was called IT. IT was the most horrible, the most repellent thing she had ever seen, far more nauseating than anything she had ever imagined with her conscious mind, or that had ever tormented her in her most terrible nightmares.
But as she had felt she was beyond fear, so now she was beyond screaming. (9.120-125)
There seems to be a limit on fear – Meg has already reached her maximum quota for the time being, so each new horror can't add anything to her emotional level. How might Meg have reacted differently if she had gone straight from her home to IT, without passing Go or collecting Mrs. Who's glasses? How might we as readers have reacted differently if the story jumped straight from one world to the other without any stops in between?