The terror, which would not end for another twenty-eight years—if it ever did end—began, so far as I know or can tell, with a boat made from a sheet of newspaper floating down a gutter swollen with rain. (1.1.1)
This quote is one of the most famous opening lines in modern literature for a reason. And it's telling that It kicks off with the words "the terror" because, after all, that's what It's all about.
And in spite of his fear, Ben found that part of him did want a balloon. (4.11.17)
This is how It operates—a really seductive comingling of fear and desire. Ben is pretty freaked out by the clown-guy walking on the ice, but he's also pretty psyched about the idea of having a magic balloon.
For the next forty minutes or so Bill sat next to him, his expectation that Eddie’s asthma attack would at any moment let up gradually fading into unease. By the time Ben Hanscom appeared, the unease had become real fear. It not only wasn’t letting up; it was getting worse. (5.3.13)
It balances a bunch of kind of fears, from the nightmarish idea of a psycho clown with magic balloons to the real-deal fear of someone dying from an asthma attack. The world is scary.
He turned, meaning to walk back to his bike—to run would be to dignify those fears and undignify himself—and then that splashing sound came again. (6.6.4)
Here's one of the, well, terrifying parts of how It operates on fear. Fearful people aren't always the most polite or dignified, and society pressures us to keep up a front of polite dignity. Sometimes, moving slowly and politely is a good way to get yourself killed.
This thought led to a sudden, irrational fear. For a moment he felt the way you did when you suddenly realized you had swum out too far and the water was over your head. There was an intuitive flash: We’re being drawn into something. Being picked and chosen. None of this is accidental. Are we all here yet? (9.10.20)
This quote makes an interesting distinction: there's irrational fear and there's rational fear. But where does "irrational" end and "intuitive" begin? How do you know if you're being a scaredy cat…or a totally reasonable human being?
You can live with fear, I think, Stan would have said if he could. Maybe not forever, but for a long, long time. It’s offense you maybe can’t live with, because it opens up a crack inside your thinking, and if you look down into it you see there are live things down there, and they have little yellow eyes that don’t blink, and there’s a stink down in that dark, and after awhile you think maybe there’s a whole other universe down there, a universe where a square moon rises in the sky, and the stars laugh in cold voices, and some of the triangles have four sides, and some have five, and some of them have five raised to the fifth power of sides. (9.11.12)
Stan doesn't kill himself because of fear. Fear is a part of life, and can be overcome. What Stan calls offense might also be termed anxiety: the un-writing of the rules that you think govern the world. Ultimately, this turns out to be a little bit too close to insanity for Stan to handle.
Following the pain and that brief bright fear, another new emotion had arisen (as all genuine emotions were new to It, although It was a great mocker of emotions): anger. (21.1.5)
This is handy-dandy: It tells us what It thinks are foundational feelings. First comes pain, then comes fear, then come all other emotions. Fear is elemental, basic, and really super-duper powerful.
Now they were coming again, and while everything had gone much as It had foreseen, something It had not foreseen had returned: that maddening, galling fear . . . that sense of Another. It hated the fear, would have turned on it and eaten it if It could have . . . but the fear danced mockingly out of reach, and It could only kill the fear by killing them. (21.3.1)
More deep thoughts from It; we learn that It can fear as well. The Losers spell fear for It just as It spells fear for the Losers.
Many adults could be used without knowing they had been used, and It had even fed on a few of the older ones over the years—adults had their own terrors, and their glands could be tapped, opened so that all the chemicals of fear flooded the body and salted the meat. But their fears were mostly too complex. The fears of children were simpler and usually more powerful. (21.3.12)
Here's the heart of it: what makes It tick. Fear is a sort of seasoning—it makes human flesh saltier and tastier. (Ew.) Adult fear is too complex; childhood fear is nice and simple and powerful. So, basically, It prefers strong, simple tastes (say: a lemon bar) to complex, adult tastes (say: an aged cheddar).
He could feel everything running out of him along with his life’s blood…all the rage, all the pain, all the fear, all the confusion and hurt. (22.5.22)
It has a pretty positive view of death—the moment of dying drains away all hurt and fear and anxiety. This is sort of a antidote to the fear we all experience during our lives. It's hopeful…well, almost.