What use is grief to a horse?

The thing is, I'm desperate. You see, I'm wearing that horse's head myself. That's the feeling. All reined up in old language and old assumptions, straining to jump clean-hoofed on to a whole new track of being I only suspect is there. I can't see it, because my educated, average head is being held at the wrong angle. I can't jump because the bit forbids it, and my own basic force--my horsepower, if you like--is too little. The only thing I know for sure is this: a horse's head is finally unknowable to me.

--Peter Shaffer, Equus

I suspect I'll be rereading this this evening. . .