Each case produces its individual vision, I think.
To me, the reading of stories and the writing of them are not related at all. In reading, the imagination wanders where it wills; in writing, it is an imagination harnessed and doing its work.
They are tools of the trade and I use them steadily, though perhaps not so much as I should.
Walter B. Pitkin: I see colors and details pretty well with my eyes shut. Since I turned forty this function has noticeably weakened. When in my twenties and early thirties I could look at a piece of white paper and see, in faint, swimmy colors projected on it, the things I was imagining. My capacity to visualize has been unusually intense, as psychological tests have repeatedly shown. At the end of a day's work I can see the minutest details of the objects I have dealt with; the grain in the wood of my desk, the shadows on my office floor, the colors and forms in the street. I can see these at night just before going to sleep; and I used to get myself to sleep by watching the parade of visions!
All mathematics was extremely difficult for me in school, but chiefly because I had poor teachers. Geometry still is almost a black art to me, although higher mathematics is fairly easy.
My response to what I read is uncomfortably excessive. In handling the manuscripts of other writers I am constantly seeing more in the scenes than the writers themselves saw; and they have often told me this.
I have no stock visions of types. But I do tend to reproduce a series of real persons or objects from my experience, when I read about a similar one.
I do not resent the presence of many images and pictures in a story.
My imagination behaves very differently when reading from its manner when writing. But I confess that I can not adequately describe the difference. So much can be said of it. When I read I "follow the leader" and do not run off into my own channels; but when I am writing my fancy runs wild and I think of the most preposterous and remote things which—as later analysis often shows—have indirect and obscure connections with the idea I am working over. When reading I am passive, more or less; when writing, I am active. There is a curious difference, over and above this, in the nature of my emotional responses; and this rather stumps me to set down on paper. It seems as if I give deeper and surer emotional reactions to the content of what I read than I do to what I am fancying when in the midst of writing. I find that calculating and constructing makes me deliberate and a degree cool toward the subject-matter. This is the result of deliberate intellectualizing, of course.
I have always considered the functions of imagination as the basic "tools of the trade."